Microbiology sheet
(1&2)
LECTURER: intro to microbiology
CORRECTED BY : Tamara Shawabkah
& Mohammad Jomaa
DATE: 18/9 + 22/9
Region in the body that don’t have microorganisms:
1) Blood
2) CSF
3) Upper part of stomach
Why Study Microbes?
1. Microbes and Man in Sickness and Health
• Parasitism; Pathogens (disease causing) • Infectious disease is leading cause of death in developing countries (45%). • Commensalisms; Natural Microbiota (do no harm) • Example :E.coli which is have rule in 1)absorption of vitamin K
2)digestion of un digested food 3)barrier of infection (by control the pH)
• Mutualisms; Natural Microbiota (do us good)
2. Major Modern Applications (Biotechnology):
• Recombinant DNA technology; cloning • Industrial Applications (antibiotics; chemical production via fermentation) • Sewage treatment to decompose organic matter • Bioremediation of toxic waste
3. The Role of Microbes in Ecosystems
• Sources for drug discovery (antibiotics & antiviral drugs) • Cycling of Elements (ecosystem management; global climate change) • Agriculture (crop diseases; nutrient enhancement)
Biotechnology & Bioremediation
• Biotechnology- when humans manipulate (micro)organisms to make products in an industrial setting
– Genetic engineering- create new products and “genetically modified organisms” (GMOs)
– Recombinant DNA technology- technology used to engineer GMOs capable of synthesizing desirable proteins (i.e. medicines, hormones, and enzymes)
• Bioremediation - activity of microbes in the environment
helping to restore stability or clean up toxic pollutants
– Oil spills
– Chemical spills
– Water and sewage treatment
The microbial world is made up of microorganisms and viruses.
Microbiology is the branch of biological sciences concerned with the study of
these microbes. Microorganisms are unicellular organisms (capable of existence as single cells), too
small to be seen with the naked eye. Among all forms of life on the earth,
microorganisms predominate in numbers of species and in biomass, but their
occurrence is generally under appreciated because of their small size and the need for
a microscope to see individual cells.
Although a light microscope is generally required to visualize a single microbial cell,
microbial colonies and communities can readily be observed in nature. Viruses are
noncellular entities and cannot be considered microorganisms. Viruses and cellular
microorganisms are considered microbes.
The term organism is a descriptive term that implies cellular life. Hence, micro-
organisms are a type of cellular life that is microscopic in size.
Viruses are not considered microorganisms because they are not cells. Viruses
consist of nucleic acid (DNA or RNA) enclosed in a protein coat. They lack many
essential properties of cells, including membranes, ribosomes and metabolic enzymes.
Viruses are considered microbes, but not microorganisms, and hence are not "alive".
Which are the microorganisms?
• Life forms, or other self replicating entity, that requires microscopy technology to be clearly visualized.
• All prokaryotic and many eukaryotic life forms.
• Many are unicellular, sometimes cells are organized in filaments or clumps, and others are complex with only a portion of their life cycle being microscopic.
• Most can carry out life processes independently from other cells, others are highly parasitic.
• They often require specialized techniques for their study: microscopy, culturing, biochemical and molecular.
Slide 6
We have two domain 1) prokaryotic 2) eukaryotic
This is major domain fold the organism
Difference between prokaryotic and eukaryotic
**Eukaryotic >>true nucleus, nucleus membrane, cytoplasmic
organelles (Golgi apparatus mitochondria …)
**prokaryotic>> means that is primitive >>there is no nucleus ,
nuclear material distributed in one part of the cytoplasm
In fact the prokaryotic cell nucleus called “nucleoid”
Nucleoid: it is the region where the chromosomes locate
Note: ribosomes present in both (eukaryotic and prokaryotic) but
there is deferent between them
In prokaryotic ribosome called 70s
In eukaryotic ribosomes called 80s
S: تعني عامل الترسية (sedimentation coefficient) ويتم حساب كميتها تجهاز
الطرد المركسي
subunitsmall subunit and large subunit:Each ribosomes contain 2
Small subunit Large subunit
40s 50s Eukaryotic
30s 50s prokaryotic
**The Eukaryotic cell would be about 50x bigger than the
prokaryotic cell
Slide 7 minute: 8
In prokaryotic cell >>the cell have DNA in the cytoplasm and they
have extra chromosomes
Extra chromosomes: is an DNA but it is independent from the
normal cell DNA and it is replication too
These extra chromosomes called plasmide
The gene that’s located on plasmid it’s not necessary for the
growth of bacteria ..While the shape and metabolism is
determined by normal chromosomes which is basic for bacteria
cell
من مثال : شخص لون عيونه زرقاء واخر سوداء ..هنا ال يمكن ان تتغير لون العيون
االزرق لالسود او العكس وكذلك البكتيريا ال يمكن ان يتغير شكلها بعد فترة ..الن هذه
…الصفات
Carried on the gene on the chromosome (normal chromosome)
What is the characteristic determined by plasmide ??
Eukaryotic Cell Prokaryotic Cell
Nucleus Present Absent
Number of chromosomes More than one One--but not true chromosome: Plasmids
Cell Type Usually multicellular Usually unicellular (some cyanobacteria may be
multicellular)
True Membrane bound Nucleus Present Absent
Example Animals and Plants Bacteria and Archaea
Genetic Recombination Meiosis and fusion of
gametes
Partial, undirectional transfers DNA
Microtubules Present Absent or rare
Endoplasmic reticulum Present Absent
Mitochondria Present Absent
Cytoskeleton Present May be absent
DNA wrapping on proteins.
Eukaryotes wrap
their DNA around
proteins called
histones.
Multiple proteins act together to fold and
condense prokaryotic DNA.
The trait that are not essential for the growth of bacteria for
example >>antibiotics resistant; enzyme production; toxins
transfer
Why?? Bactria are sensitive to x antibiotics. After period of time
the bacteria resistant to x antibiotic ….why?? Because gene that
code of resistance of antibiotics could o plasmide (jumping gene)
Bacteria can gain gene on plasmide and can eliminate it and can
transport it to another bacteria …and it is important in clinical
medicine to treat patients
وبالتالي ممكن ان plasmideومة والحساسية محمولة على هذا يعني ان صفة المقا
تنتقل من بكتيريا الخرى
Genes transfer from one bacteria to one another by 1)conjugation
(most popular) 2)transduction
Archea is an old bacteria that’s live in extreme environment such
as (high and low pH, high osmotic pressure, high and low
temperature)
Eukaryotic cell >> all organisms in the world expect 1)bacteria
2)Archea 3)green blue Algi
Eukaryotic Cell Prokaryotic Cell
Nucleus Present Absent
Number of chromosomes More than one One--but not true chromosome: Plasmids
Cell Type Usually multicellular Usually unicellular (some cyanobacteria may be
multicellular)
True Membrane bound Nucleus Present Absent
Example Animals and Plants Bacteria and Archaea
Genetic Recombination Meiosis and fusion of
gametes
Partial, undirectional transfers DNA
Microtubules Present Absent or rare
Endoplasmic reticulum Present Absent
Mitochondria Present Absent
Cytoskeleton Present May be absent
DNA wrapping on proteins.
Eukaryotes wrap
their DNA around
proteins called
histones.
Multiple proteins act together to fold and
condense prokaryotic DNA.
There is no bacteria with
constant characteristic for
its life (always change)
Minute: 19
histone is a basic protein
In prokaryotic cell there is some bacteria do photosynthesis so
that it has chlorophyll separated in cytoplasm not in chloroplast
Flagella is use to move
Ribosomes Larger smaller
Vesicles Present Present
Golgi apparatus Present Absent
Chloroplasts Present (in plants) Absent; chlorophyll scattered in the
cytoplasm
Flagella
Microscopic in
size; membrane
bound; usually
arranged as nine
doublets
surrounding two
singlets
Submicroscopic in size, composed of
only one fiber
Permeability of Nuclear
Membrane
Selective not present
Plasma membrane with
steroid
Yes Usually no
Cell wall
Only in plant
cells and fungi
(chemically
simpler)
Usually chemically complexed
Vacuoles Present Present
Cell size 10-100um 1-10u
Ribosomes Larger smaller
Vesicles Present Present
Golgi apparatus Present Absent
Chloroplasts Present (in plants) Absent; chlorophyll scattered in the
cytoplasm
Flagella
Microscopic in
size; membrane
bound; usually
arranged as nine
doublets
surrounding two
singlets
Submicroscopic in size, composed of
only one fiber
Permeability of Nuclear
Membrane
Selective not present
Plasma membrane with
steroid
Yes Usually no
Cell wall
Only in plant
cells and fungi
(chemically
simpler)
Usually chemically complexed
Vacuoles Present Present
Cell size 10-100um 1-10u
Eukaryotic Cell Prokaryotic Cell
Nucleus Present Absent
Number of chromosomes More than one One--but not true chromosome: Plasmids
Cell Type Usually multicellular Usually unicellular (some cyanobacteria may be
multicellular)
True Membrane bound Nucleus Present Absent
Example Animals and Plants Bacteria and Archaea
Genetic Recombination Meiosis and fusion of
gametes
Partial, undirectional transfers DNA
Microtubules Present Absent or rare
Endoplasmic reticulum Present Absent
Mitochondria Present Absent
Cytoskeleton Present May be absent
DNA wrapping on proteins.
Eukaryotes wrap
their DNA around
proteins called
histones.
Multiple proteins act together to fold and
condense prokaryotic DNA.
No histones
Note : flagella don’t have any association or related to the cell
speed in motion
Note :there is no relation ship between number of flagella and
active motion
Flagella determine only if there is motile or no
**bacteria can change its shape in respond to several factors such
as : 1)enviroment 2)radiation
in procaryoti cell there is some bactreia have steriod
for example>>myoplasma hominis one of the smallest bacteria
don’t have cell wall …..but it have plasma membrane with steroid
(3 lyers of steroid) ….(normal bacteria cell have cell wall and plsma
membrane without steroid)
steroid it is a fatty lyer have rule and affect many things like
motile and stabilty to the cell and many other things.
In prokaryotic cell >> the cell wall is very important part of the
bacteria because it is use in determing the type of gram stan (+ or -)
This part is very important in clinical medicine in diagnosis
Ribosomes Larger smaller
Vesicles Present Present
Golgi apparatus Present Absent
Chloroplasts Present (in plants) Absent; chlorophyll scattered in the
cytoplasm
Flagella
Microscopic in
size; membrane
bound; usually
arranged as nine
doublets
surrounding two
singlets
Submicroscopic in size, composed of
only one fiber
Permeability of Nuclear
Membrane
Selective not present
Plasma membrane with
steroid
Yes Usually no
Cell wall
Only in plant
cells and fungi
(chemically
simpler)
Usually chemically complexed
Vacuoles Present Present
Cell size 10-100um 1-10u
Ribosomes Larger smaller
Vesicles Present Present
Golgi apparatus Present Absent
Chloroplasts Present (in plants) Absent; chlorophyll scattered in the
cytoplasm
Flagella
Microscopic in
size; membrane
bound; usually
arranged as nine
doublets
surrounding two
singlets
Submicroscopic in size, composed of
only one fiber
Permeability of Nuclear
Membrane
Selective not present
Plasma membrane with
steroid
Yes Usually no
Cell wall
Only in plant
cells and fungi
(chemically
simpler)
Usually chemically complexed
Vacuoles Present Present
Cell size 10-100um 1-10u
By using gram stain >>(gram - =red // gram + =purple)
If we use lysosome or pencillin or others enzyme we can change
the structure of cell wall and change it.
Cell wall in prokaryotic cell called “peptidoglycan” or “mural”
Minute :28
Cell size… In prokyrotic cell >> myoplasma hominis it is very small
and don’t have cell wall …but it has nuclear material in cytoplasm
and have plasmic membrain which have steroide that supply and
give stability to the cell
Slide 9
Biologists recognize the existence of two fundamentally different types of cells in the microbial world,
called procaryotic and eucaryotic cells.
1. Eucaryotic cells have a "true" nucleus (the region of the cell that contains genetic information or DNA) that enclosed in a nuclear
membrane
2. Prokaryotic cells are said to have a "primitive" nucleus because their DNA is not enclosed within a nuclear membrane. The nuclear
region of a prokaryotic cell is sometimes referred to as a nucleoid, but
never as a nucleus.
Procaryotic and Eucaryotic cells
Eucaryotic cells are always bounded by a membrane, just as prokaryotic cells are.
Some eucaryotic cells are also surrounded by a cell wall, but eucaryotic cells do not have capsules.
Mitochondria are present in nearly all eucaryotic cells and produce the cell's energy by breaking down food.
Chloroplasts, in contrast, are present only in plants and algae and are used in photosynthesis, the process through which
the organism uses energy from the sun to build sugars.
Taxonomy of Life:
The classification, or grouping, of organisms based on common characters used to reflect their evolutionary relatedness. Types of groups, taxa, are arranged in a hierarchy from the most general (Domain) to most specific.
3 Domains based on molecular analysis of ribosomal RNA. (Carl Woese 1980s)
Two prokaryote domains: Bacteria and Archaea
A single Eukaryote domain.
Many Phyla within each domain.
Divided to 3 domains and each domains have several groups
Domain : Eukaryotic
Bacteria prokaryotic
Archae prokaryotic
Usually bacteria in lab live in normal temperature 37 (middle
temperature)
Every line represents a period of time and note the eukaryotic
and archea are closed to each other but prokaryotic its far away
Humans
• Domain: Eukarya • Kingdom: Animalia • Phylum: Chordata • Class: Mammalia • Order: Primata • Family: Hominidae • Group: Homo • Species: sapiens
Intestinal Bacterium
• Domain: Bacteria • (no kingdom) • Phylum: Proteobacteria • Class: γ-proteobacteria • Order: Enterobacteriales • Family: Enterobacteriaceae • Genus: Escherichia • Species: coli
Difference in taxonomy between us and them
The underline suffix “ales” mean order and the suffix “aceae”
mean family
Minute :34
Binomial nomenclature: (1+2)
1)Genus 2)species (must be italic or underlined)
Genus name must begin in capital letter
Example : E.coli O157:H7 >>(it is subspecies)
O mean >> one of somatic antigen and the number 157 it is one type of several type begin to numbering from 1
H mean >>flagella antigen and the number is type of several type
**bacteria may be capsulated or not capsulated (capsulated one is more dangerous to us than non-capsulated one)
One of the capsule functions is being anti-phagocytic and allows the bacteria to proliferation and distribute in your body
Minute :42
Bacteria is more common than Fungi
Deffernt in ways of motile
Amoeba>> Pseudopodia
Ciliate >>cilia
Flagellate >>flagella
Viruses: An infectious particle with an acellular organization of protein and nucleic acids (RNA or DNA), and lacking independent metabolism.
It requires the metabolism of a host cell in order to replicate. Viruses are about 50 to 200 nm in size.
Viruses can’t survive without living with another cell
Viruses that’s surrounded by envelpe called “enveloped viruse”
Compound microscope = bright filed microscope =student microscope
Elctron microscope 600,000x
Compound microscope 1000x
contain only one DNA or RNA and not both with protien Viruse
conain only protien Prion
contane only RNA and protien Virone
Prion: An infectious aberrant brain protein that causes abnormal aggregation of similar normal brain proteins; no nucleic acids. Causes dementia and madness.