Embed Size (px)
Citation preview
1
Staphylococcus aureus in polymicrobial infections: impact on pathogenesis 1
Nisha Nair1, Raja Biswas1, Friedrich Götz2, Lalitha Biswas1 2
1Amrita Center for Nanosciences and Molecular Medicine, Amrita Institute of Medical 3
Sciences, AIMS – Ponekkara, Edapally, Cochin, Kerala, India. 4
2Microbial Genetics, Interfaculty Institute for Microbiology and Infection Medicine 5
Tübingen (IMIT), University of Tübingen, Germany. 6
Abbreviations: TSS: Toxic shock syndrome; SE: enterotoxins; TSST-1: Toxic shock 7
syndrome toxin-1; PSM: Phenol-soluble modulins; H2O2: Hydrogen peroxide; SCV: 8
small-colony variants; VRSA: Vancomycin resistant S. aureus; TNF-α: Tumor necrosis 9
factor-alpha; TSS: Toxic shock syndrome; SEB: staphylococcal enterotoxin B; PVL: 10
Panton-Valentine leukocidin; Esp: Extracellular serine protease. 11
Keywords: Staphylococcus aureus, intraspecies and interspecies interactions, polymicrobial 12
infections, Pseudomonas aeruginosa, Streptococcus pneumonia, Enterococcus faecalis, 13
Candida albicans, influenza Virus. 14
Running Head: Interactions of Staphylococcus aureus 15
Conflicts of Interest: All authors, no conflicts 16
*Corresponding author: Lalitha Biswas, Amrita Centre for Nanoscience and Molecular 17
medicine, Amrita Institute of Medical Sciences, AIMS – Ponekkara, Edapally, Cochin, PIN: 18
682041, Kerala, India. 19
Phone: +91-0484- 4001234 (Extn: 6345); Email: [email protected] 20
21
22
23
IAI Accepts, published online ahead of print on 17 March 2014Infect. Immun. doi:10.1128/IAI.00059-14Copyright © 2014, American Society for Microbiology. All Rights Reserved.
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
2
Abstract: 24
Polymicrobial infections involving S. aureus exhibit enhanced disease severity and morbidity. 25
We reviewed the nature of polymicrobial interactions between S. aureus and other bacterial, 26
fungal and viral co-colonizers. Microbes that were frequently recovered from the infection site 27
with S. aureus are Haemophilus influenzae, Enterococcus faecalis, P. aeruginosa, S. 28
pneumoniae, Corynebacterium sp, Lactobacillus sp, Candida albicans and influenza virus. 29
Detailed analysis of several in vitro and in vivo observations demonstrate that S. aureus exhibits 30
cooperative relations with C. albicans, E. faecalis, H. influenzae and influenza virus and 31
competitive relations with P. aeruginosa, Streptococcus pneumoniae, Lactobacillus sp, and 32
Corynebacterium sp. Both of these interactions influence changes in S. aureus that alter its 33
characteristics in terms of colony formation, protein expressions, pathogenicity and antibiotic 34
susceptibility. 35
Introduction: 36
S. aureus is an opportunistic and resilient human pathogen that colonizes the mucosal surfaces. 37
It is the causative agent of many serious acute and chronic infections. The anterior nares are the 38
primary reservoirs of S. aureus. Asymptomatic colonization occurs in approximately 20% of 39
the normal population, 60% are transiently colonized, while 20% appear to be rarely or never 40
colonized (1). Extranasal colonization of S. aureus also takes place in several locations, 41
including the skin, rectum, axillae, vagina, pharynx, and gastrointestinal tract (2). 42
S. aureus causes numerous infections, including skin infections (boils, furuncles, styes, 43
impetigo), surgical and trauma wounds, urinary tract infections, gastrointestinal tract infections, 44
pneumonia, osteomyelitis, endocarditis, thrombophlebitis, mastitis, meningitis, infections on 45
indwelling medical devices, toxic shock syndrome (TSS) and septicaemia (3, 4). The factors 46
contributing to the rise of this organism as a formidable pathogen involve multiple mechanisms 47
of virulence. These include the evolution of strategies to resist antibiotics and evade host 48
defenses, as well as the production of an arsenal of virulence factors such as capsule, coagulase, 49
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
3
lipase, hyaluronidase, protein A, fibrinogen binding proteins, fibronectin binding proteins and 50
secreted toxins like enterotoxins (SEs), toxic shock syndrome toxin-1 (TSST-1), 51
Panton-Valentine leucocidin (PVL), hemolysins and phenol-soluble modulins (PSMs) (5-9). 52
Several studies have confirmed S. aureus as one of the co-infecting microbes in many 53
patients with polymicrobial infections (10). The interactions between S. aureus and the 54
co-existing microbes are either cooperative as with C. albicans (11-14), E. faecalis (15, 16), H. 55
influenzae (17-19) and influenza virus (20, 21) or competitive as with P. aeruginosa, 56
Streptococcus pneumoniae (18, 19), Lactobacillus sp (22-27), and Corynebacterium sp (17, 57
28-30). Irrespective of whether the interactions are cooperative (Fig. 1) or competitive (Fig. 2) 58
S. aureus within a community behaves differently in comparison to its monomicrobial growth. 59
This article focuses on reviewing the significance of interactions between S. aureus and other 60
microorganisms and its effect on disease progression and outcome. 61
Interactions with Candida: Both Candida species and S. aureus usually exist as commensals 62
that colonize human mucosal surfaces. Furthermore they are opportunistic pathogens and cause 63
a wide range of infections such as sepsis, pneumonia, denture stomatitis, and neonatal sepsis. 64
Despite causing a number of infections independently, C. albicans and S. aureus can also be 65
co-isolated from several diseases like cystic fibrosis, superinfection of burn wounds, urinary 66
tract infections, diabetic foot wounds and from the surfaces of various biomaterials, including 67
dentures, voice prostheses, implants, endotracheal tubes, feeding tubes and catheters (31-34) . 68
Biofilm embedded microbes are extremely resistant to both host clearance mechanisms, 69
and antimicrobial agents. S. aureus and C. albicans are often isolated concurrently from mixed 70
bacterial–fungal biofilms on implanted medical devices (35). During biofilm associated 71
co-infections, C. albicans forms the base of the biofilm and facilitates the biofilm formation of 72
S. aureus. The C. albicans hyphal protein agglutinin-like sequence 3 (Als3p) mediates the 73
binding of S. aureus with C. albicans hyphae (14, 36, 37). Within the polymicrobial biofilm S. 74
aureus exhibits enhanced resistance towards vancomycin (13). 75
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
4
Independent studies demonstrated that the interactions between S. aureus and C. albicans 76
enhanced the disease severity in several ways (33, 38). Candidal infections cause physical 77
damage to organ walls, allowing S. aureus to penetrate the internal organs more easily. S. 78
aureus on the other hand secretes different proteases that help C. albicans to enhance its 79
adhesion to the mucosal layer (12). During systemic infections, both organisms help each other 80
to evade phagocytic killing mediated by polymorphonuclear leukocytes (PMNs). C. albicans 81
secretes a proteinase that degrades the Fc portion of immunoglobulin G (IgG) and greatly 82
reduces the opsonizing activity of human PMNs against S. aureus (39). On the other hand, S. 83
aureus secrete coagulase and extracellular fibrinogen binding proteins (Efb) that protect 84
Candida sp from PMNs mediated phagocytosis. Coagulase activates prothrombin which 85
mediates conversion of fibrinogen to fibrin. Formation of fibrin clots surrounding the candidal 86
cells helps Candida sp to evade phagocytic killing by granulocytes (40). Additionally, Efb 87
binds to C3 complement and interferes with complement activation and C3 mediated 88
opsonization (41). The cooperative infection of C. albicans and S. aureus represents a 89
significant therapeutic challenge and their co-isolation from blood is an indication of dire 90
prognosis (42). 91
Competitive or antagonistic relationships between C. albicans and S. aureus have also 92
been reported where the quorum sensing molecule farnesol secreted by C. albicans inhibits the 93
biofilm formation of S. aureus. Farnesol disrupts the S. aureus cell membrane integrity and 94
thereby its viability. Additionally, in vitro results demonstrated that farnesol treated S. aureus 95
showed enhanced susceptibility to a variety of clinically important antibiotics (43). However it 96
is as yet unclear how much farnesol C. albicans secretes under in vivo conditions and whether 97
the secreted concentrations are sufficient to inhibit the growth of S. aureus in vivo. Nevertheless, 98
all available in vivo data suggest that S. aureus and C. albicans exist in synergy. Apart from 99
Candida albicans, S. aureus was also isolated together with Candida tropicalis, Candida 100
parapsiolosis and Trichosporon asahii (44, 45). 101
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
5
Interactions with influenza virus: The mechanisms of interaction of S. aureus with influenza 102
virus are much more complex than the interactions between S. aureus and C. albicans. 103
Super-infection of influenza virus and S. aureus is one of the major causes of severe influenza 104
pneumonia, prolonged inflammation and higher mortality rates. This represents the best-known 105
model of bacterial-viral co-infection (20). 106
Influenza virus A infection promotes and enhances the nasopharyngeal adherence of S. 107
aureus (46). On the other hand S. aureus promotes the infectivity and spread of the influenza 108
virus particles. Hemagglutinin (HA), a trimeric glycoprotein, present in multiple copies in the 109
membrane envelope of influenza virus, is responsible for the attachment of the virus particle to 110
sialic acid containing receptors of the host ciliated columnar epithelial cells. Proteolytic 111
cleavage of the hemagglutinin is an important prerequisite for the infectivity of the influenza 112
virus and for the spread of the virus in the host organism and associated pathogenicity. Several 113
strains of S. aureus have been found to secrete serine proteases that activate infectivity of 114
influenza virus by proteolytic cleavage of the hemagglutinin (21). 115
Co-infections of S. aureus and influenza virus may lead to severe disease outcome as influenza 116
virus infection enhances the deleterious effects of Staphylococcal enterotoxin B (SEB) and 117
Toxic shock syndrome toxin -1 (TSST-1) (47, 48). SEB and TSST-1 are superantigens that 118
activate T-cells in an uncontrolled manner and cause massive systemic release of cytokines. 119
Concurrent S. aureus and influenza viral infection induce enterotoxin mediated massive release 120
of tumor necrosis factor-alpha (TNF-α) and interferon gamma (IFNγ). This results in fever, 121
rash, hypotension, tissue injury, and shock. It has been hypothesized that the lethal synergism 122
between concurrent influenza infection and S. aureus superantigen exposure may contribute to 123
sudden and unexpected death from influenza infection (49). 124
Interactions with other bacteria: The majority of the interactions between S. aureus and other 125
bacterial species are competitive in nature and only a few interactions are cooperative. 126
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
6
Cooperative interactions of S. aureus exist with H. influenza and E. faecalis. Competitive 127
interactions are observed between S. aureus and other bacteria viz., Pseudomonas aeruginosa, 128
Streptococcus pneumoniae, Lactic acid bacteria, Corynebacterium sp or S. epidermidis. 129
Competitive interactions do not mean that these organisms completely inhibit the colonization 130
of S. aureus, rather S. aureus employs numerous defense strategies for its survival, counter 131
attacking the competing bacteria and surviving in the same ecological niche as that of the 132
competing bacteria. Cooperative or competitive interactions lead to the development of more 133
persistent S. aureus strains with altered colony morphology, antibiotic resistance and increased 134
virulence. The interactions of S. aureus with other bacterial species are listed below: 135
1. Interactions with Haemophilus influenzae: S. aureus and H. influenzae both colonize the 136
nasopharynx and, in some instances, the conjunctivae and genital tract. H. influenzae reaches 137
higher colony densities when the resident colonizer is S. aureus. The higher H. influenzae 138
colony densities have been attributed to the availability of nutrients that S. aureus provides to 139
facilitate its growth (19). S. aureus produces three major hemolysins (α, β and γ) which lyse 140
erythrocytes by compromising their membrane integrity (50). The hemolysis of erythrocytes by 141
S. aureus secreted hemolysins release nutrients such as hemin and nicotinamide adenine 142
dinucleotide (NAD), which are vital for the growth of H. influenzae (51-53). Margolis et 143
al., demonstrated the synergistic interactions of S. aureus and H. influenzae in the rat 144
nasopahrynx (19). However, Pettigrew et al., and Bergh et al., studied the nasal microflora 145
composition among children and have reported antagonism or negative association between S. 146
aureus and H. influenzae (54, 55). Both these studies were designed to determine the microflora 147
composition among children of age group between 6-36 months. 148
Interactions with Pseudomonas aeruginosa: The relation between S. aureus and P. 149
aeruginosa is competitive in nature, although both organisms are frequently found together 150
under clinical settings. They have common niches within the host, for example, cystic fibrosis 151
(CF) patient's lung, peritoneum of dialysis patients, catheters, diabetic foot wounds and other 152
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
7
type of wounds caused by skin injury or skin burn (44, 56). S. aureus is often reported as the 153
primary pathogen infecting the lungs of the CF patients followed by P. aeruginosa. Although 154
co-infections of both these pathogens are very common under in vivo conditions, several 155
independent in vitro studies demonstrated that when co-cultured together, P. aeruginosa thrives 156
better than S. aureus (57-59). The better survival of P. aeruginosa is attributed to its ability to 157
produce respiratory toxins such as, pyocyanin, hydrogen cyanide and alkyl-hydroxyquinoline 158
N-oxides that can block the electron transport pathway, thereby inhibiting the growth of S. 159
aureus and other pathogenic staphylococci (57, 58). 160
Despite its sensitivity to respiratory inhibitors, S. aureus does not get completely cleared 161
away by P. aeruginosa. To counter the effect of the respiratory toxins produced by P. 162
aeruginosa, S. aureus forms electron transport deficient small-colony variants (SCVs) that 163
grow as tiny, non-pigmented colonies (57). Purified 4-hydroxy-2-heptylquinoline-N-oxide 164
(HQNO) or pyocyanin produced by P. aeruginosa are sufficient to induce SCV selection in S. 165
aureus (57, 59). These SCVs are auxotrophic to hemin or menadione and are resistant to 166
antibiotics, especially aminoglycosides, trimethoprim-sulphamethoxazol (60) and the host 167
antimicrobial peptide lactoferricin B (8). The resistance of SCVs is due in part to their severely 168
decreased membrane potential as well as their reduced growth rate and metabolic processes. 169
These SCVs also persist better than their normal counterparts. 170
P. aeruginosa also produces a 20-kDa endopeptidase, LasA, which selectively cleaves S. 171
aureus peptidoglycan. LasA cleaves the glycyl–glycine and glycyl–alanine bonds of the 172
pentaglycine interpeptide bridge in the S. aureus peptidoglycan and induces lysis (61, 62). 173
Using the rat model of infection, Mashburn et al., showed that P. aeruginosa can lyse S. aureus 174
cells, and the iron-containing proteins released from the lysed S. aureus cells serve as the source 175
of iron, thereby increasing pathogenic potential of P. aeruginosa (63, 64). However, this result 176
is yet to be validated in clinical settings. P. aeruginosa exhibits a similar kind of antagonistic 177
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
8
relationship towards S. epidermidis, as well as species representatives of S. haemolyticus, S. 178
saprophyticus, S. hyicus, S. muscae, and S. lugdunensis (58). 179
Interactions with Streptococcus pneumoniae: The relation between S. pneumoniae and S. 180
aureus is antagonistic and similar to that of P. aeruginosa and S. aureus. S. pneumoniae and S. 181
aureus colonize the upper respiratory tract of children and compete with each other for the same 182
niche (59, 65, 66). Various studies have shown that colonization of the upper airway by S. 183
pneumoniae is negatively correlated with S. aureus colonization, and children who are 184
vaccinated with pneumococcal conjugate vaccines are at major risk of S. aureus infections (18). 185
This inverse relation suggests that one organism interferes with the colonization of the other. In 186
vitro data demonstrates that hydrogen peroxide (H2O2) produced by S. pneumoniae is a 187
by-product of aerobic metabolism and is responsible for the antagonistic relationship between 188
these two pathogens (67). H2O2 leads to the production of DNA-damaging hyperoxides through 189
the Fenton reaction that induces the SOS response. SOS response induces resident prophages, 190
resulting in the lysis of lysogenic staphylococci. Because the vast majority of S. aureus strains 191
are lysogenic, the production of H2O2 is a very effective anti-staphylococcal strategy of S. 192
pneumonia. H2O2, at concentrations typically produced by pneumococci, kills lysogenic but not 193
non-lysogenic staphylococci (68). Pneumococci, however, are not SOS-induced on exposure to 194
H2O2 as they are resistant to the DNA damaging effects of the Fenton reaction (69). 195
It is interesting to note that S. aureus, which produces so many antioxidants and free 196
radical scavengers including catalase, alkyl hydroperoxide reductase, superoxide dismutase 197
(SodA and SodM) and staphyloxanthin (16, 70), is susceptible to H2O2 produced by S. 198
pneumoniae. A possible explanation could be that that the amount of free radical scavengers 199
that S. aureus produces are not sufficient enough to neutralize all the H2O2 produced by S. 200
pneumoniae. Yochay et al., demonstrated that staphylococcal species that secrete higher 201
concentrations of catalase are resistant to S. pneumoniae (67). 202
However, other studies hypothesize that the production of hydrogen peroxide may not 203
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
9
be the main reason for the antagonistic relation between these pathogens in vivo (71). Although 204
both pathogens colonize the upper respiratory tract, their microniche is different. Therefore 205
direct antagonism mediated by H2O2 is an unlikely reason for their antagonism. Rather, the 206
antibody response generated during S. pneumoniae infection although ineffective in restricting 207
this pathogen itself but is effective in providing cross protection against S. aureus (71, 72). 208
Interactions with Lactic acid bacteria (LAB): Lactic acid bacteria (LAB) are composed of a 209
heterogeneous bacterial group comprising non-sporulating, Gram positive cocci and bacilli that 210
are able to ferment sugars predominantly into lactic acid. This leads to an acidification of the 211
environment down to a pH of 3.5. LAB colonizes the gut and urogenital tract and contributes to 212
defense against S. aureus mediated food poisoning and genital infections. The 213
anti-staphylococcal activity of LAB strains are attributed by the production of H2O2, organic 214
acids, antimicrobial proteins, biosurfactants, surface proteins and quorum sensing inhibitors. 215
The most commonly studied members of intestinal and vaginal LAB include L. acidophilus, L. 216
casei, L. fermentum, L. salivarius, L. rhamnosus, L. gasseri, L. vaginalis, L. johnsonii and L. 217
delbrueckii (25, 73-75). 218
Similar to S. pneumoniae; LAB produced hydrogen peroxide (H2O2) inhibits the growth 219
of S. aureus (76, 77). Additionally, LAB secretes organic acids (lactic, acetic, formic, caproic, 220
propionic, butyric and valeric acids) that inhibit the growth of S. aureus (78). LAB produced 221
bacteriocins interfere with cell wall structure and biosynthesis, and form pores in the S. aureus 222
membrane (79). Among the bacteriocins produced by LAB, the most important are nisin 223
produced by Lactococcus lactis; Pediocin produced by Pepidococcus acidilactici; and Lacticin 224
3147 produced by Lactococcus lactis DPC 3147 (79, 80). 225
Apart from inhibiting the growth of S. aureus using H2O2, organic acids and bacteriocins LAB 226
competes with S. aureus for the host cell adhesion sites. Biosurfactants and surface proteins of 227
LAB strains are involved in this competitive exclusion process. L. fermentum, L. acidophilus, L. 228
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
10
crispatus CRL 1266, L. paracasei ssp. paracasei CRL 1289, L. salivarius CRL 1328, L. 229
rhamnosus GG, Lactococcus. lactis ssp. lactis and Propionibacterium freudenreichii ssp. 230
shermani were shown to disrupt the adherence of S. aureus to the intestinal and urogenital tract 231
by competing for the same adhesion sites. Some LAB strains were also shown to displace 232
previously adhered S. aureus from the vaginal epithelial cells (27). In a recent study it was also 233
shown that the small signaling molecules, cyclic dipeptides cyclo(L-Tyr-LPro) and 234
cyclo(L-Phe-L-Pro), produced by the human vaginal isolate L. reuteri RC-14, are able to 235
interfere with the staphylococcal quorum-sensing system agr, a key regulator of virulence 236
genes, and repress the expression of staphylococcal exotoxin TSST-1 (81). 237
To counter the detrimental effects of LABs S. aureus produces bacteriocins that have 238
antibacterial activity against LAB. For example, the S. aureus secretes bacteriocins like 239
staphylococcin Au-26, Bac1829, BacR1, Aureocin A70 and Aureocin A53 that inhibit the 240
growth of lactobacilli (80). 241
Interactions with Corynebacterium sp: S. aureus and Corynebacterium sp are two of the most 242
important species in the skin and nasopharynx. Both organisms are associated with 243
catheter-related infections. A lower incidence of S. aureus colonization has been observed in 244
individuals heavily colonized by Corynebacterium sp (C. accolens, C. pseudodiptheriticum and 245
C. tuberculostearicum). Corynebacterium sp utilizes competitive exclusion strategies similar to 246
LAB in competing with S. aureus for the same adhesion site with host mucosal epithelial cells 247
(30). No bacteriocin-like activity of Corynebacterium sp against S. aureus has been reported. 248
However, a number of bacteriocins secreted by S. aureus are active against Corynebacterium sp. 249
These bacteriocins include Bac1829 (17), Aureocin A70 (29), Aureocin A53 (82) and 250
Staphylococcin 188 (28). 251
Interactions with S. epidermidis: Besides these interactions, S. aureus is also known to 252
interact with members of the same genus. Several reports indicate antagonistic relationships 253
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
11
between S. aureus and S. epidermidis. Both S. aureus and S. epidermidis are opportunistic and 254
nosocomial pathogens. Unlike S. aureus, which causes severe acute infections, S. epidermidis 255
frequently causes chronic infections and has an exceptional capacity to attach to the indwelling 256
medical devices during surgery and form biofilms. The presence of S. epidermidis in the nasal 257
cavities has been reported to correlate with the absence of S. aureus (83). Similar to S. 258
pneumoniae this pathogen uses multiple strategies to inhibit S. aureus colonization. These 259
include production of autoinducing peptide (AIP), phenol-soluble modulins (PSM) and 260
bacteriocins. The production of virulence factors and other extracellular proteins in 261
staphylococci is globally regulated by the accessory gene regulatory system (agr). Agr encodes 262
a two-component signaling pathway whose activating ligand is AIP, which is also encoded by 263
agr (84). The AIPs can activate the agr response in the other members of the same group but 264
have a mutually inhibitory effect between members of different groups. Based on the agr loci 265
present, S. aureus have been divided into 4 major groups: agr-1Sa to agr-4Sa, and S. epidermidis 266
into 3 major groups: agr-1Se to agr-3Se (85). S. epidermidis AIP has been proven to inhibit the 267
activity of agr-1Sa to agr-3Sa and thereby suppress the expression of virulence factors such as 268
the α-toxin, β-toxin, δ-toxin, serine protease, DNase, fibrinolysin, enterotoxin B and toxic 269
shock syndrome toxin-1 in S. aureus. Among S. aureus AIPs, only agr-4Sa weakly inhibits the 270
activity of agr-1Se (30, 86). 271
Additionally, S. epidermidis secretes extracellular serine protease (Esp) that alone or in 272
a combination with host β-defensin 2 eliminates S. aureus biofilms. Esp cleaves S. aureus major 273
autolysin (Atl) protein and interferes with its function (87). Activity of Atl is necessary for 274
DNA release and biofilm formation of S. aureus (88). Phenol-soluble modulins (PSMγ and 275
PSMδ) and bacteriocins (Pep5, epidermin, epilancin K7 and epicidin 280) produced by S. 276
epidermidis inhibit the growth of S. aureus. S. epidermidis secreted PSM peptides cooperate 277
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
12
with each other and with the host antimicrobial peptide, LL-37 to exert selective antimicrobial 278
action against S. aureus (9, 89). 279
Interactions with Enterococcus faecalis: The anterior nares are generally considered to be the 280
primary site of colonization of S. aureus, however low concentrations (≤105 CFU/g of feces) of 281
this organism co-colonize the intestinal tracts together with E. faecalis in healthy humans. Both 282
S. aureus and E. faecalis normally exist as commensals, but they can turn into opportunistic 283
pathogens causing urinary tract infections, bacteremia and infective endocarditis (15). Apart 284
from the intestinal tract, E. faecalis and S. aureus are frequently isolated from the respiratory 285
tract, urinary tract, chronic foot ulcers and from diabetic foot wounds (44). The interaction 286
between E. faecalis and S. aureus is neither truly synergistic nor antagonistic. 287
A lot of studies were focused on the mechanisms by which S. aureus acquired 288
Vancomycin resistance gene from E. faecalis. Vancomycin resistant S. aureus (VRSA) strains 289
emerged due to horizontal transfer of Tn1546 transposon containing vanA gene from 290
vancomycin-resistant E. faecalis (90-92). The transposon Tn1546 harboring vanA gene present 291
on the plasmid pAM830 is related to the Inc18 family of broad-host-range conjugative plasmids 292
and is responsive to the pheromone, cAM373, secreted by the plasmid-free (recipient) strains of 293
E. faecalis. cAM373 triggers the process of conjugation leading to the transfer of vanA gene 294
from the Vancomycin resistant E. faecalis (donor) strains to the vancomycin susceptible E. 295
faecalis strains (recipient) (93). S. aureus is also known to secrete a peptide staph-cAM373 296
(Amino acid sequence: AIFILAA) with an activity similar to E. faecalis-cAM373 (Amino acid 297
sequence: AIFILAS) that triggers the process of conjugation between vancomycin resistant E. 298
faecalis (donor) and S. aureus (recipient) (94). This conjugation results in the transfer of vanA 299
gene from E. faecalis to S. aureus. Genetic analysis of several vancomycin resistant S. aureus 300
(VRSA) strains showed that transposon Tn1546 harboring the vanA gene either jumped into a 301
staphylococcal plasmid or integrated into the S. aureus chromosome (16, 91, 95). The 302
acquisition of vanA by S. aureus resulted in an incorporation of D-alanyl-D-lactate 303
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
13
(D-Ala-D-Lac) precursors into the peptidoglycan instead of D-Alanine-D-Alanine 304
(D-Ala-D-Ala). The E. faecalis and S. aureus cell wall harboring the D-Ala-D-Lac precursors 305
has 1,000-fold-less affinity for vancomycin, a drug that is considered as the last resort antibiotic 306
to treat MRSA infections (96). Interactions between these two bacteria have led to the rise in 307
multi-drug resistant staphylococci. 308
Conclusion: Most infections are polymicrobial in nature and can be seen in almost every niche 309
in the human body, particularly in mucosal surfaces where different species of micro-organisms 310
such as bacteria, fungi and viruses co-exist as communities. S. aureus is one of the most 311
common pathogens found in the polymicrobial infections. In polymicrobial infections S. aureus 312
differentially modulates host immune responses and disease severity and acquires altered 313
growth and antibiotic susceptibility patterns. 314
The altered immune response during polymicrobial infections could be beneficial or 315
detrimental for S. aureus. For example, influenza virus infection inhibits Th17 mediated 316
adaptive immune response (97). Activated Th17 cells are necessary for protection against S. 317
aureus infection, because this subset of T cells enhance neutrophil recruitment to sites of 318
infection, and kill S. aureus (98, 99). Therefore, Th17 cell mediated immune activation is 319
necessary to limit S. aureus infections. By inhibiting Th17 cell mediated immune response and 320
subsequent neutrophil infiltration influenza virus helps S. aureus to colonize and cause severe 321
secondary bacterial pneumonia (97, 100). Contrary to immune suppression mediated by 322
influenza virus that aids S. aureus, S. pnuemoniae mediated immune activation is detrimental to 323
S. aureus. The antibody response generated during S. pneumoniae infection against its 324
glyceraldehyde-3-phosphate dehydrogenase, although ineffective in inducing 325
opsonophagocytic killing of S. pnuemoniae, can cross-react with staphylococcal protein 326
1-pyrroline-5-carboxylate dehydrogenase and induce opsonophagocytic killing of S. aureus (71, 327
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
14
72). S. pnuemoniae itself is protected from opsonophagocytic killing due to its anti-opsonic 328
polysaccharide capsule. 329
Additionally, S. aureus in polymicrobial infections displays enhanced persistence and 330
antibiotic tolerance. S. aureus acquired vancomycin resistance genes from E. faecalis and 331
became resistant to vancomycin (16, 91, 95). S. aureus during coinfection with C. albicans 332
showed increased vancomycin resistance (13, 101). This bacteria forms electron transport 333
deficient small-colony variants during co-infection with P. aeruginosa (57, 58). These SCVs 334
persist better than their normal counterparts and are resistant to aminoglycosides and 335
trimethoprim-sulphamethoxazols (102). 336
A 23 valent polysaccharide vaccine against S. pneumoniae, which was recently introduced into 337
the market indeed prevented S. pneumoniae nasopahryangeal colonization but the vaccinated 338
individuals were at the increased risk for S. aureus nasal colonization (72). Therefore, 339
prevention of one pathogenic infection provides opportunities to the competing pathogens to 340
cause disease. These findings highlight the potential complications that could arise from 341
conventional treatment and disease prevention strategies that target a single organism, thereby 342
necessitating the need to introduce modified therapeutic approaches that take into account the 343
co-infecting organisms. Several strategies could be used to address the treatment difficulties in 344
polymicrobial infections of S. aureus. One could be the use of combined vaccines against two 345
or more coinfecting microbes; however such vaccines are still in the experimental stages. The 346
next approach could be the use of anti-microbial drugs judiciously. A coinfection of S. aureus 347
and influenza virus should be treated with anti-viral and appropriate anti-bacterial drugs. A 348
third approach is the use of LAB strains to prevent not all but some of the S. aureus infections. 349
Probiotic LAB bacteria can prevent intestinal and urogenital tract co-infections. Studies showed 350
that regular intake of probiotic LAB, fermented milk can even reduce S. aureus colonization in 351
the upper respiratory tract. Similarly, probiotic LABs also confer protection against influenza 352
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
15
virus by modulating innate immunity. Thus, Probiotic bacteria can be used to prevent S. aureus 353
and influenza virus coinfections. 354
In summary, S. aureus in polymicrobial infections represents a major clinical challenge than S. 355
aureus in monomicrobial infections. The coexisting microbes significantly influence the 356
outcome of the infection by altering the invasion ability, growth, gene expression and drug 357
sensitivity patterns. Further investigations are required to design appropriate treatment 358
strategies to tackle polymicrobial infections mediated by S. aureus. 359
Acknowledgements: 360
NN is supported by a doctoral fellowship from Indian Council of Medical Research (ICMR; 361
45/16/2011/IMM-BMS), RB is supported by Ramalingaswami fellowship, Department of 362
Biotechnology (DBT); Government of India. This study was supported by DBT 363
(BT/PR13125/GBD/27/193/2009) grant to RB and ICMR (AMR/14/2011-ECD1) grant to LB. 364
We thank Professor Shantikumar V Nair for valuable comments and for critically reviewing the 365
manuscript. 366
Fig. 1. Cooperative interactions between S. aureus and other microbes. S. aureus can 367
co-colonize with H. influenzae, E. faecalis, C. albicans and influenza virus. S. aureus induced 368
lysis of the red blood cells (RBC) leads to the release of Hemin and NAD which act as nutrients 369
and support the growth of H. influenzae. S. aureus secretes proteases that cleave the host sialic 370
acid receptor and increase the infectivity of influenza virus by releasing the virus from host cell 371
surface. S. aureus gained vancomycin resistance from E. faecalis due to horizontal gene transfer, 372
and became more resistant to antibiotics during co-infection with C. albicans. Symbols: SA= S. 373
aureus; VRSA=Vancomycin resistant S. aureus; VREF= Vancomycin resistant E. faecalis. 374
Fig. 2. Competitive interactions between S. aureus and other microbes. S. aureus exhibits 375
antagonism towards P. aeruginosa, Streptococcus sp and Lactobacillus sp. P. aeruginosa 376
produced phenazine (PZ), hydrogen cyanide (HCN), Quinolone oxidase (QO) and pyocyanin 377
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
16
(PY) results in the respiratory blockage of S. aureus, which in turn leads to the formation of 378
small colony variants (SCVs). SCVs are more persistent and are resistant to antibiotics. 379
Lactobacillus sp and Streptococcus sp inhibit the growth of S. aureus by producing hydrogen 380
peroxide (H2O2). S. aureus produces staphyloxanthin and catalase, which neutralize the toxic 381
effects of H2O2. Additionally Lactobacillus sp produce organic acids and bacteriocins that limit 382
the growth of S. aureus. Certain S. aureus strains also produce bacteriocins like Staphylococcin 383
Au 26, which in turn inhibit the growth of lactobacilli. Blocked arrows indicate antagonism and 384
arrows indicate survival strategies of S. aureus. 385
References: 386
1. Williams, R. E. 1963. Healthy carriage of Staphylococcus aureus: its prevalence and 387
importance. Bacteriological reviews 27:56-71. 388
2. Wertheim, H. F., D. C. Melles, M. C. Vos, W. van Leeuwen, A. van Belkum, H. A. 389
Verbrugh, and J. L. Nouwen. 2005. The role of nasal carriage in Staphylococcus 390
aureus infections. Lancet Infect Dis. 5: 751–762. 391
3. G�tz, F., T. Bannerman and K. H. Schleifer. 2006. The Genera Staphylococcus and 392
Macrococcus. Prokaryotes 4:5–75. 393
4. McCaig, L. F., L. C. McDonald, S. Mandal, and D. B. Jernigan. 2006. 394
Staphylococcus aureus-associated skin and soft tissue infections in ambulatory care. 395
Emerging infectious diseases 12:1715-1723. 396
5. Garnier, F., A. Tristan, B. Francois, J. Etienne, M. Delage-Corre, C. Martin, N. 397
Liassine, W. Wannet, F. Denis, and M. C. Ploy. 2006. Pneumonia and new 398
methicillin-resistant Staphylococcus aureus clone. Emerg. Infect. Dis.12:498-500. 399
6. Joo, H. S., G. Y. Cheung, and M. Otto. 2011. Antimicrobial activity of 400
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
17
community-associated methicillin-resistant Staphylococcus aureus is caused by 401
phenol-soluble modulin derivatives. J. Biol. Chem. 286:8933-8940. 402
7. Prevost, G., L. Mourey, D. A. Colin, and G. Menestrina. 2001. Staphylococcal 403
pore-forming toxins. Curr. Top. Microbiol. Immunol. 257:53-83. 404
8. Schreiner, J., D. Kretschmer, J. Klenk, M. Otto, H. J. Buhring, S. Stevanovic, J. M. 405
Wang, S. Beer-Hammer, A. Peschel, and S. E. Autenrieth. 2013. Staphylococcus 406
aureus phenol-soluble modulin peptides modulate dendritic cell functions and increase 407
in vitro priming of regulatory T cells. J. Immunol. 190:3417-3426. 408
9. Varella Coelho, M. L., J. D. Santos Nascimento, P. C. Fagundes, D. J. Madureira, 409
S. S. Oliveira, M. A. Vasconcelos de Paiva Brito, and C. Freire Bastos Mdo. 2007. 410
Activity of staphylococcal bacteriocins against Staphylococcus aureus and 411
Streptococcus agalactiae involved in bovine mastitis. Res. Microbiol. 158:625-630. 412
10. Finelli, L., A. Fiore, R. Dhara, L. Brammer, D. K. Shay, L. Kamimoto, A. Fry, J. 413
Hageman, R. Gorwitz, J. Bresee, and T. Uyeki. 2008. Influenza-associated pediatric 414
mortality in the United States: increase of Staphylococcus aureus coinfection. Pediatrics 415
122:805-811. 416
11. Adam, B., G. S. Baillie, and L. J. Douglas. 2002. Mixed species biofilms of Candida 417
albicans and Staphylococcus epidermidis. J. Med. Microbiol. 51:344-349. 418
12. El-Azizi, M. A., S. E. Starks, and N. Khardori. 2004. Interactions of Candida 419
albicans with other Candida spp. and bacteria in the biofilms. J. Appl. Microbiol. 420
96:1067-1073. 421
13. Harriott, M. M., and M. C. Noverr. 2009. Candida albicans and Staphylococcus 422
aureus form polymicrobial biofilms: effects on antimicrobial resistance. 423
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
18
Antimicrob. Agents Chemother. 53:3914-3922. 424
14. Peters, B. M., M. A. Jabra-Rizk, M. A. Scheper, J. G. Leid, J. W. Costerton, and M. 425
E. Shirtliff. 2010. Microbial interactions and differential protein expression in 426
Staphylococcus aureus -Candida albicans dual-species biofilms. FEMS Immunol. Med. 427
Microbiol. 59:493-503. 428
15. Ray, A. J., N. J. Pultz, A. Bhalla, D. C. Aron, and C. J. Donskey. 2003. Coexistence 429
of vancomycin-resistant enterococci and Staphylococcus aureus in the intestinal tracts 430
of hospitalized patients. Clin. Infect. Dis. 37:875-881. 431
16. Flannagan, S. E., and D. B. Clewell. 2002. Identification and characterization of genes 432
encoding sex pheromone cAM373 activity in Enterococcus faecalis and Staphylococcus 433
aureus. Mol. Microbiol. 44:803-817. 434
17. Crupper, S. S., and J. J. Iandolo. 1996. Purification and partial characterization of a 435
novel antibacterial agent (Bac1829) Produced by Staphylococcus aureus KSI1829. 436
Appl. Environ. Microbiol. 62:3171-3175. 437
18. Madhi, S. A., P. Adrian, L. Kuwanda, C. Cutland, W. C. Albrich, and K. P. 438
Klugman. 2007. Long-term effect of pneumococcal conjugate vaccine on 439
nasopharyngeal colonization by Streptococcus pneumoniae--and associated interactions 440
with Staphylococcus aureus and Haemophilus influenzae colonization--in HIV-Infected 441
and HIV-uninfected children. J. Infect. Dis. 196:1662-1666. 442
19. Margolis, E., A. Yates, and B. R. Levin. 2010. The ecology of nasal colonization of 443
Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus: the 444
role of competition and interactions with host's immune response. BMC microbial. 445
10:59. 446
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
19
20. Niemann, S., C. Ehrhardt, E. Medina, K. Warnking, L. Tuchscherr, V. Heitmann, 447
S. Ludwig, G. Peters, and B. Loffler. 2012. Combined action of influenza virus and 448
Staphylococcus aureus panton-valentine leukocidin provokes severe lung epithelium 449
damage. J. Infect. Dis. 206:1138-1148. 450
21. Tashiro, M., P. Ciborowski, M. Reinacher, G. Pulverer, H. D. Klenk, and R. Rott. 451
1987. Synergistic role of staphylococcal proteases in the induction of influenza virus 452
pathogenicity. Virology 157:421-430. 453
22. Gan, B. S., J. Kim, G. Reid, P. Cadieux, and J. C. Howard. 2002. Lactobacillus 454
fermentum RC-14 inhibits Staphylococcus aureus infection of surgical implants in rats. 455
J. Infect. Dis. 185:1369-1372. 456
23. Li, J., W. Wang, S. X. Xu, N. A. Magarvey, and J. K. McCormick. Lactobacillus 457
reuteri-produced cyclic dipeptides quench agr-mediated expression of toxic shock 458
syndrome toxin-1 in staphylococci. Proc. Natl. Acad. Sci. USA 108:3360-3365. 459
24. Otero, M. C., and M. E. Nader-Macias. 2006. Inhibition of Staphylococcus aureus by 460
H2O2-producing Lactobacillus gasseri isolated from the vaginal tract of cattle. Anim 461
Reprod Sci 96:35-46. 462
25. Varma, P., N. Nisha, K. R. Dinesh, A. V. Kumar, and R. Biswas. 2011. 463
Anti-infective properties of Lactobacillus fermentum against Staphylococcus aureus 464
and Pseudomonas aeruginosa. J Mol Microbiol Biotechnol 20:137-143. 465
26. Vesterlund, S., M. Karp, S. Salminen, and A. C. Ouwehand. 2006. Staphylococcus 466
aureus adheres to human intestinal mucus but can be displaced by certain lactic acid 467
bacteria. Microbiology 152:1819-1826. 468
27. Zarate, G., and M. E. Nader-Macias. 2006. Influence of probiotic vaginal lactobacilli 469
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
20
on in vitro adhesion of urogenital pathogens to vaginal epithelial cells. Lett. Appl. 470
Microbiol. 43:174-180. 471
28. Saeed, S., S. Ahmad, and S. A. Rasool. 2004. Antimicrobial spectrum, production and 472
mode of action of staphylococcin 188 produced by Staphylococcus aureus 188. Pak. J. 473
Pharm. Sci. 17:1-8. 474
29. dos Santos Nascimento, J., K. R. dos Santos, E. Gentilini, D. Sordelli, and C. de 475
Freire Bastos Mdo. 2002. Phenotypic and genetic characterisation of 476
bacteriocin-producing strains of Staphylococcus aureus involved in bovine mastitis. Vet 477
Microbiol 85:133-144. 478
30. Lina, G., F. Boutite, A. Tristan, M. Bes, J. Etienne, and F. Vandenesch. 2003. 479
Bacterial competition for human nasal cavity colonization: role of Staphylococcal agr 480
alleles. Appl. Environ. Microbiol. 69:18-23. 481
31. Valenza, G., D. Tappe, D. Turnwald, M. Frosch, C. Konig, H. Hebestreit, and M. 482
Abele-Horn. 2008. Prevalence and antimicrobial susceptibility of microorganisms 483
isolated from sputa of patients with cystic fibrosis. J. Cyst. Fibros. 7:123-127. 484
32. Shirtliff, M. E., B. M. Peters, and M. A. Jabra-Rizk. 2009. Cross-kingdom 485
interactions: Candida albicans and bacteria. FEMS Microbiol. Lett. 299:1-8. 486
33. Peters, B. M., and M. C. Noverr. 2013. Candida albicans-Staphylococcus aureus 487
polymicrobial peritonitis modulates host innate immunity. Infect. Immun. 488
81:2178-2189. 489
34. Peters, B. M., R. M. Ward, H. S. Rane, S. A. Lee, and M. C. Noverr. 2013. Efficacy 490
of ethanol against Candida albicans and Staphylococcus aureus polymicrobial biofilms. 491
Antimicrob. Agents Chemother. 57:74-82. 492
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
21
35. Kojic, E. M., and R. O. Darouiche. 2004. Candida infections of medical devices. Clin. 493
Microbiol. Rev. 17:255-267. 494
36. Klotz, S. A., B. S. Chasin, B. Powell, N. K. Gaur, and P. N. Lipke. 2007. 495
Polymicrobial bloodstream infections involving Candida species: analysis of patients 496
and review of the literature. Diagn. Microbiol. Infect. Dis. 59:401-406. 497
37. Peters, B. M., E. S. Ovchinnikova, B. P. Krom, L. M. Schlecht, H. Zhou, L. L. 498
Hoyer, H. J. Busscher, H. C. van der Mei, M. A. Jabra-Rizk, and M. E. Shirtliff. 499
2012. Staphylococcus aureus adherence to Candida albicans hyphae is mediated by the 500
hyphal adhesin Als3p. Microbiology 158:2975-2986. 501
38. Morales, D. K., and D. A. Hogan. 2010. Candida albicans interactions with bacteria in 502
the context of human health and disease. PLoS pathog. 6:e1000886. 503
39. Kaminishi, H., H. Miyaguchi, T. Tamaki, N. Suenaga, M. Hisamatsu, I. Mihashi, H. 504
Matsumoto, H. Maeda, and Y. Hagihara. 1995. Degradation of humoral host defense 505
by Candida albicans proteinase. Infect. Immun. 63:984-988. 506
40. Fehrmann, C., K. Jurk, A. Bertling, G. Seidel, W. Fegeler, B. E. Kehrel, G. Peters, 507
K. Becker, and C. Heilmann. 2013. Role for the fibrinogen-binding proteins coagulase 508
and Efb in the Staphylococcus aureus-Candida interaction. Int J Med Microbiol 509
303:230-238. 510
41. Lee, L. Y., M. Hook, D. Haviland, R. A. Wetsel, E. O. Yonter, P. Syribeys, J. 511
Vernachio, and E. L. Brown. 2004. Inhibition of complement activation by a secreted 512
Staphylococcus aureus protein. J. Infect. Dis. 190:571-579. 513
42. Wisplinghoff, H., T. Bischoff, S. M. Tallent, H. Seifert, R. P. Wenzel, and M. B. 514
Edmond. 2004. Nosocomial bloodstream infections in US hospitals: analysis of 24,179 515
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
22
cases from a prospective nationwide surveillance study. Clin. Infect. Dis. 39:309-317. 516
43. Jabra-Rizk, M. A., T. F. Meiller, C. E. James, and M. E. Shirtliff. 2006. Effect of 517
farnesol on Staphylococcus aureus biofilm formation and antimicrobial susceptibility. 518
Antimicrob. Agents Chemother. 50:1463-1469. 519
44. Chellan, G., S. Shivaprakash, S. Karimassery Ramaiyar, A. K. Varma, N. Varma, 520
M. Thekkeparambil Sukumaran, J. Rohinivilasam Vasukutty, A. Bal, and H. 521
Kumar. 2010. Spectrum and prevalence of fungi infecting deep tissues of lower-limb 522
wounds in patients with type 2 diabetes. J. Clin. Microbiol. 48:2097-2102. 523
45. Popescu, G. A., T. Prazuck, D. Poisson, and C. Picu. 2005. A "true" polymicrobial 524
endocarditis: Candida tropicalis and Staphylococcus aureus--to a drug user. Case 525
presentation and literature review. Rom. J. Intern. Med. 43:157-161. 526
46. Davison, V. E., and B. A. Sanford. 1982. Factors influencing adherence of 527
Staphylococcus aureus to influenza A virus-infected cell cultures. Infect. Immun. 528
37:946-955. 529
47. Yarovinsky, T. O., M. P. Mohning, M. A. Bradford, M. M. Monick, and G. W. 530
Hunninghake. 2005. Increased sensitivity to staphylococcal enterotoxin B following 531
adenoviral infection. Infect. Immun. 73:3375-3384. 532
48. MacDonald, K. L., M. T. Osterholm, C. W. Hedberg, C. G. Schrock, G. F. 533
Peterson, J. M. Jentzen, S. A. Leonard, and P. M. Schlievert. 1987. Toxic shock 534
syndrome. A newly recognized complication of influenza and influenza like illness. 535
Jama 257:1053-1058. 536
49. Zhang, W. J., S. Sarawar, P. Nguyen, K. Daly, J. E. Rehg, P. C. Doherty, D. L. 537
Woodland, and M. A. Blackman. 1996. Lethal synergism between influenza infection 538
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
23
and staphylococcal enterotoxin B in mice. J. Immunol. 157:5049-5060. 539
50. Nilsson, I. M., O. Hartford, T. Foster, and A. Tarkowski. 1999. Alpha-toxin and 540
gamma-toxin jointly promote Staphylococcus aureus virulence in murine septic arthritis. 541
Infect. Immun. 67:1045-1049. 542
51. Orlova, O. E., S. I. Elkina, N. E. Iastrebova, N. P. Vaneeva, V. V. Sergeev, N. G. 543
Kalina, and M. M. Tokarskaia. 2005. Influence of nicotinamide adenine dinucleotide 544
and hemin concentrations on the growth of Haemophilus influanzae type b and the 545
synthesis of capsular polysaccharide. Zh. Mikrobiol. Epidemiol. Immunobiol. 4:12-15. 546
52. Kemmer, G., T. J. Reilly, J. Schmidt-Brauns, G. W. Zlotnik, B. A. Green, M. J. 547
Fiske, M. Herbert, A. Kraiss, S. Schlor, A. Smith, and J. Reidl. 2001. NadN and e 548
(P4) are essential for utilization of NAD and nicotinamide mononucleotide but not 549
nicotinamide riboside in Haemophilus influenzae. J. Bacteriol. 183:3974-3981. 550
53. Artman, M., E. Domenech, and M. Weiner. 1983. Growth of Haemophilus influenzae 551
in simulated blood cultures supplemented with hemin and NAD. J. Clin. Microbiol. 552
18:376-379. 553
54. Pettigrew, M. M., J. F. Gent, K. Revai, J. A. Patel, and T. Chonmaitree. 2008. 554
Microbial interactions during upper respiratory tract infections. Emerg. Infect. Dis. 555
14:1584-1591. 556
55. van den Bergh, M. R., G. Biesbroek, J. W. Rossen, W. A. de Steenhuijsen Piters, A. 557
A. Bosch, E. J. van Gils, X. Wang, C. W. Boonacker, R. H. Veenhoven, J. P. Bruin, 558
D. Bogaert, and E. A. Sanders. 2012. Associations between pathogens in the upper 559
respiratory tract of young children: interplay between viruses and bacteria. PloS one 560
7:e47711. 561
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
24
56. Holley, J. L., J. Bernardini, and B. Piraino. 1992. Polymicrobial peritonitis in 562
patients on continuous peritoneal dialysis. Am. J. Kidney Dis. 19:162-166. 563
57. Biswas, L., R. Biswas, M. Schlag, R. Bertram, and F. Gotz. 2009. Small-colony 564
variant selection as a survival strategy for Staphylococcus aureus in the presence of 565
Pseudomonas aeruginosa. Appl. Environ. Microbiol. 75:6910-6912. 566
58. Voggu, L., S. Schlag, R. Biswas, R. Rosenstein, C. Rausch, and F. Götz. 2006. 567
Microevolution of cytochrome bd oxidase in Staphylococci and its implication in 568
resistance to respiratory toxins released by Pseudomonas. J. Bacteriol. 188:8079-8086. 569
59. Hoffman, L. R., E. Deziel, D. A. D'Argenio, F. Lepine, J. Emerson, S. McNamara, 570
R. L. Gibson, B. W. Ramsey, and S. I. Miller. 2006. Selection for Staphylococcus 571
aureus small-colony variants due to growth in the presence of Pseudomonas aeruginosa. 572
Proc. Natl. Acad. Sci. USA 103:19890-19895. 573
60. Vaudaux, P., W. L. Kelley, and D. P. Lew. 2006. Staphylococcus aureus small colony 574
variants: difficult to diagnose and difficult to treat. Clin. Infect. Dis. 43:968-970. 575
61. Kessler, E., M. Safrin, J. C. Olson, and D. E. Ohman. 1993. Secreted LasA of 576
Pseudomonas aeruginosa is a staphylolytic protease. J. Biol. Chem. 268:7503-7508. 577
62. Lache, M., W. R. Hearn, J. W. Zyskind, D. J. Tipper, and J. L. Strominger. 1969. 578
Specificity of a bacteriolytic enzyme from Pseudomonas aeruginosa. J. Bacteriol. 579
100:254-259. 580
63. Mashburn, L. M., A. M. Jett, D. R. Akins, and M. Whiteley. 2005. Staphylococcus 581
aureus serves as an iron source for Pseudomonas aeruginosa during in vivo coculture. J. 582
Bacteriol. 187:554-566. 583
64. Palmer, K. L., L. M. Mashburn, P. K. Singh, and M. Whiteley. 2005. Cystic fibrosis 584
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
25
sputum supports growth and cues key aspects of Pseudomonas aeruginosa physiology. 585
J. Bacteriol. 187:5267-5277. 586
65. Bogaert, D., A. van Belkum, M. Sluijter, A. Luijendijk, R. de Groot, H. C. Rumke, 587
H. A. Verbrugh, and P. W. Hermans. 2004. Colonisation by Streptococcus 588
pneumoniae and Staphylococcus aureus in healthy children. Lancet 363:1871-1872. 589
66. Regev-Yochay, G., R. Dagan, M. Raz, Y. Carmeli, B. Shainberg, E. Derazne, G. 590
Rahav, and E. Rubinstein. 2004. Association between carriage of Streptococcus 591
pneumoniae and Staphylococcus aureus in Children. JAMA 292:716-720. 592
67. Regev-Yochay, G., K. Trzcinski, C. M. Thompson, R. Malley, and M. Lipsitch. 593
2006. Interference between Streptococcus pneumoniae and Staphylococcus aureus: In 594
vitro hydrogen peroxide-mediated killing by Streptococcus pneumoniae. J. Bacteriol. 595
188:4996-5001. 596
68. Selva, L., D. Viana, G. Regev-Yochay, K. Trzcinski, J. M. Corpa, I. Lasa, R. P. 597
Novick, and J. R. Penades. 2009. Killing niche competitors by remote-control 598
bacteriophage induction. Proc. Natl. Acad. Sci. USA 106:1234-1238. 599
69. Pericone, C. D., S. Park, J. A. Imlay, and J. N. Weiser. 2003. Factors contributing to 600
hydrogen peroxide resistance in Streptococcus pneumoniae include pyruvate oxidase 601
(SpxB) and avoidance of the toxic effects of the fenton reaction. J. Bacteriol. 602
185:6815-6825. 603
70. Clauditz, A., A. Resch, K. P. Wieland, A. Peschel, and F. Götz. 2006. 604
Staphyloxanthin plays a role in the fitness of Staphylococcus aureus and its ability to 605
cope with oxidative stress. Infect. Immun. 74:4950-4953. 606
71. Lijek, R. S., and J. N. Weiser. 2013. Co-infection subverts mucosal immunity in the 607
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
26
upper respiratory tract. Curr. Opin. Immunol. 24:417-423. 608
72. Lijek, R. S., S. L. Luque, Q. Liu, D. Parker, T. Bae, and J. N. Weiser. 2012. 609
Protection from the acquisition of Staphylococcus aureus nasal carriage by 610
cross-reactive antibody to a pneumococcal dehydrogenase. Proc. Natl. Acad. Sci. USA 611
109:13823-13828. 612
73. Reid, G., and J. Burton. 2002. Use of Lactobacillus to prevent infection by pathogenic 613
bacteria. Microbes Infect. 4:319-324. 614
74. Reid, G. 2008. Probiotic Lactobacilli for urogenital health in women. J. Clin. 615
Gastroenterol. 42 Suppl 3 Pt 2:S234-236. 616
75. Walter, J., and R. Ley. 2011. The human gut microbiome: ecology and recent 617
evolutionary changes. Annu. Rev. Microbiol. 65:411-429. 618
76. Ocana, V. S., A. A. de Ruiz Holgado, and M. E. Nader-Macias. 1999. Growth 619
inhibition of Staphylococcus aureus by H2O2-producing Lactobacillus paracasei subsp. 620
paracasei isolated from the human vagina. FEMS Immunol. Med. Microbiol. 23:87-92. 621
77. Hawes, S. E., S. L. Hillier, J. Benedetti, C. E. Stevens, L. A. Koutsky, P. 622
Wolner-Hanssen, and K. K. Holmes. 1996. Hydrogen peroxide-producing lactobacilli 623
and acquisition of vaginal infections. J. Infect. Dis. 174:1058-1063. 624
78. Varma, P., K. R. Dinesh, K. K. Menon, and R. Biswas. 2010. Lactobacillus 625
fermentum isolated from human colonic mucosal biopsy inhibits the growth and 626
adhesion of enteric and foodborne pathogens. J. Food Sci. 75:M546-551. 627
79. Drider, D., G. Fimland, Y. Hechard, L. M. McMullen, and H. Prevost. 2006. The 628
continuing story of class IIa bacteriocins. Microbiol. Mol. Biol. Rev. 70:564-582. 629
80. Charlier, C., M. Cretenet, S. Even, and Y. Le Loir. 2009. Interactions between 630
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
27
Staphylococcus aureus and lactic acid bacteria: an old story with new perspectives. Int. J. 631
Food. Microbiol. 131:30-39. 632
81. Li, J., W. Wang, S. X. Xu, N. A. Magarvey, and J. K. McCormick. 2011. 633
Lactobacillus reuteri-produced cyclic dipeptides quench agr-mediated expression of 634
toxic shock syndrome toxin-1 in staphylococci. Proc. Natl. Acad. Sci. USA 635
108:3360-3365. 636
82. Netz, D. J., R. Pohl, A. G. Beck-Sickinger, T. Selmer, A. J. Pierik, C. Bastos Mdo, 637
and H. G. Sahl. 2002. Biochemical characterisation and genetic analysis of aureocin 638
A53, a new, atypical bacteriocin from Staphylococcus aureus. J. Mol. Biol. 639
319:745-756. 640
83. Frank, D. N., L. M. Feazel, M. T. Bessesen, C. S. Price, E. N. Janoff, and N. R. Pace. 641
2010. The human nasal microbiota and Staphylococcus aureus carriage. PloS one 642
5:e10598. 643
84. Malone, C. L., B. R. Boles, and A. R. Horswill. 2007. Biosynthesis of Staphylococcus 644
aureus autoinducing peptides by using the synechocystis DnaB mini-intein. Appl. 645
Environ. Microbiol. 73:6036-6044. 646
85. Dufour, P., S. Jarraud, F. Vandenesch, T. Greenland, R. P. Novick, M. Bes, J. 647
Etienne, and G. Lina. 2002. High genetic variability of the agr locus in Staphylococcus 648
species. J. Bacteriol. 184:1180-1186. 649
86. Otto, M., H. Echner, W. Voelter, and F. Gotz. 2001. Pheromone cross-inhibition 650
between Staphylococcus aureus and Staphylococcus epidermidis. Infect. Immun. 651
69:1957-1960. 652
87. Iwase, T., Y. Uehara, H. Shinji, A. Tajima, H. Seo, K. Takada, T. Agata, and Y. 653
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
28
Mizunoe. 2010. Staphylococcus epidermidis Esp inhibits Staphylococcus aureus 654
biofilm formation and nasal colonization. Nature 465:346-349. 655
88. Chen, C., V. Krishnan, K. Macon, K. Manne, S. V. Narayana, and O. Schneewind. 656
2013. Secreted proteases control autolysin-mediated biofilm growth of Staphylococcus 657
aureus. J. Biol. Chem. 288:29440-29452. 658
89. Cogen, A. L., K. Yamasaki, K. M. Sanchez, R. A. Dorschner, Y. Lai, D. T. 659
MacLeod, J. W. Torpey, M. Otto, V. Nizet, J. E. Kim, and R. L. Gallo. 2010. 660
Selective antimicrobial action is provided by phenol-soluble modulins derived from 661
Staphylococcus epidermidis, a normal resident of the skin. J. Invest. Dermatol. 662
130:192-200. 663
90. Clark, N. C., L. M. Weigel, J. B. Patel, and F. C. Tenover. 2005. Comparison of 664
Tn1546-like elements in vancomycin-resistant Staphylococcus aureus isolates from 665
Michigan and Pennsylvania. Antimicrob. Agents Chemother. 49:470-472. 666
91. Perichon, B., and P. Courvalin. 2009. VanA-type vancomycin-resistant 667
Staphylococcus aureus. Antimicrob. Agents Chemother. 53:4580-4587. 668
92. Zhu, W., P. R. Murray, W. C. Huskins, J. A. Jernigan, L. C. McDonald, N. C. 669
Clark, K. F. Anderson, L. K. McDougal, J. C. Hageman, M. Olsen-Rasmussen, M. 670
Frace, G. J. Alangaden, C. Chenoweth, M. J. Zervos, B. Robinson-Dunn, P. C. 671
Schreckenberger, L. B. Reller, J. T. Rudrik, and J. B. Patel. 2010. Dissemination of 672
an Enterococcus Inc18-Like vanA plasmid associated with vancomycin-resistant 673
Staphylococcus aureus. Antimicrob. Agents Chemother. 54:4314-4320. 674
93. Flannagan, S. E., J. W. Chow, S. M. Donabedian, W. J. Brown, M. B. Perri, M. J. 675
Zervos, Y. Ozawa, and D. B. Clewell. 2003. Plasmid content of a 676
vancomycin-resistant Enterococcus faecalis isolate from a patient also colonized by 677
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
29
Staphylococcus aureus with a VanA phenotype. Antimicrob. Agents Chemother. 678
47:3954-3959. 679
94. Muscholl-Silberhorn, A., E. Samberger, and R. Wirth. 1997. Why does 680
Staphylococcus aureus secrete an Enterococcus faecalis-specific pheromone? FEMS 681
Microbiol. Lett. 157:261-266. 682
95. Sletvold, H., P. J. Johnsen, O. G. Wikmark, G. S. Simonsen, A. Sundsfjord, and K. 683
M. Nielsen. 2010. Tn1546 is part of a larger plasmid-encoded genetic unit horizontally 684
disseminated among clonal Enterococcus faecium lineages. J. Antimicrob. 685
Chemother. 65:1894-1906. 686
96. Arthur, M., F. Depardieu, L. Cabanie, P. Reynolds, and P. Courvalin. 1998. 687
Requirement of the VanY and VanX D,D-peptidases for glycopeptide resistance in 688
enterococci. Mol. Microbiol. 30:819-830. 689
97. Kudva, A., E. V. Scheller, K. M. Robinson, C. R. Crowe, S. M. Choi, S. R. Slight, S. 690
A. Khader, P. J. Dubin, R. I. Enelow, J. K. Kolls, and J. F. Alcorn. 2011. Influenza 691
A inhibits Th17-mediated host defense against bacterial pneumonia in mice. J. Immunol. 692
186:1666-1674. 693
98. Narita, K., D. L. Hu, F. Mori, K. Wakabayashi, Y. Iwakura, and A. Nakane. 2010. 694
Role of interleukin-17A in cell-mediated protection against Staphylococcus aureus 695
infection in mice immunized with the fibrinogen-binding domain of clumping factor A. 696
Infect. Immun. 78:4234-4242. 697
99. Lin, L., A. S. Ibrahim, X. Xu, J. M. Farber, V. Avanesian, B. Baquir, Y. Fu, S. W. 698
French, J. E. Edwards, Jr., and B. Spellberg. 2009. Th1-Th17 cells mediate 699
protective adaptive immunity against Staphylococcus aureus and Candida albicans 700
infection in mice. PLoS pathog. 5:e1000703. 701
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
30
100. McHugh, K. J., S. Mandalapu, J. K. Kolls, T. M. Ross, and J. F. Alcorn. 702
2013. A novel outbred mouse model of 2009 pandemic influenza and bacterial 703
co-infection severity. PloS one 8:e82865. 704
101. Harriott, M. M., and M. C. Noverr. Ability of Candida albicans mutants to 705
induce Staphylococcus aureus vancomycin resistance during polymicrobial biofilm 706
formation. J. Antimicrob. Chemother. 54:3746-3755. 707
102. Garcia, L. G., S. Lemaire, B. C. Kahl, K. Becker, R. A. Proctor, O. Denis, P. 708
M. Tulkens, and F. Van Bambeke. 2013. Antibiotic activity against small-colony 709
variants of Staphylococcus aureus: review of in vitro, animal and clinical data. J. 710
Antimicrob. Chemother. 68:1455-1464. 711
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
Fig. 1
Hemin,NAD
VREF VRSA
NAD
H. influenzaeNutrients
SA Antibiotic resistance
RBClysis
Serine proteases
Influenza
Hemagglutinin
Influenza virus
Sialic acid receptor C. albicans
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
Fig. 2
S pneumoniae
Catalase, SOD, H2O2 reductase, StaphyloxanthinS. pneumoniae,
S. sanguinisH2O2
Staphyloxanthin
OAs (AA, LA),Bacteriocins
SAPZ, HCN, QO, PY
BacteriocinsLactobacillus sp
P. aeruginosa
Staphylococcin, Aureocin, SCVsp y , ,Au-26, Bac1829, BacR1 Antibiotic resistance
on February 3, 2018 by guest
http://iai.asm.org/
Dow
nloaded from
