kdo

sugar alcohol phosphate polymers

NAM-NAG

Pathogenic propertiesPathogenic properties

• Adherence to host surfaces/ColonizationAdherence to host surfaces/Colonization– Pili (N. gonorrheae; E. coli)– Extracellular polysaccharides (S. mutans)

• InvasivenessInvasiveness– Collagenase/Hyaluronidase (destroy “ground substance”)– Coagulase (promote fibrin “veil”)– IgA protease (H. influenza; N. gonorrheae; S. pneumoniae; P. gingivalis)

– Leucocidins (A. actinomycetemcomitans)– Antiphagocytic agents (B. forsythus; S. pneumonia; N. meningitidis)

• InflammationInflammation– Pyogenic inflammation (pus forming; neutrophils) (S. pyogenes; S. aureus)– Granulomatous inflammation (phagosome/lysosome dysregulation) (M.

tuberculosis)

ToxigenicityToxigenicity

ExotoxinExotoxin EndotoxinEndotoxinSourceSource Gr+ Gr- Gr-

OriginOrigin Secreted Cell wall

ChemistryChemistry Polypeptide LPS

ToxicityToxicity High (fatal dose ~ 1g) Low (fatal dose 100’s gs)

Clinical effectsClinical effects Fever, shock Fever, shock

AntigenicityAntigenicity Induce ↑ titers Abs (antitoxins) Poorly antigenic

VaccinesVaccines Toxoids used as vaccines No toxoids formed; no vaccines available

Heat StabilityHeat Stability thermolabile thermostable

Typical DiseasesTypical Diseases Toxic shock syndrome; cholera; tetanus; diphtheria

Gr- sepsis; endotoxic shock