2. Anthrax Bacillus anthracis
Cutaneous
anthrax

3. M A T A K U L I A H M I K R O B I O L O G I
E V I R O V I A T I
STRUKTUR SEL BAKTERI

4. Prokaryotes
Domains
Bacteria &
Archaea
Simple cells –
with no nucleus
or membrane-
bound
organelles

5. I. Bacteria Classification: Cell shape
A. Compound Light Microscope (1000X) - stained
Cocci (Coccus) Bacilli (Bacillus) Spirilli (Spirillum)
round or oval rod-shaped helically coiled

6. B. Scanning Electrom Microscope (SEM) - colorized

7. II. Classification Bacteria: Cell arrangement
1. Diplococcus (diplo=pairs)
Neisseria gonorrhoeae - Gram-negative,
causes gonorrhea
SEMStained: Compound Microscope
1000X

8. Staphylococcus aureus
Staphylococcus aureus - Causes food poisoning, toxic shock syndrome
and skin and wound infections such as scalded skin syndrome,
scarlet fever, and impetigo.
Stained: Compound Microscope
1000X
SEM (colorized)
2. staphylococcus
(staphylo- grapelike clusters)

9. 3. streptococcus
(strepto=chains)
Streptococcus pyogenes
Stained: Compound Microscope
1000X
SEM (colorized)

10. 4. Streptobacillus

11. Bacteria
 Structure
Cell wall – unique, peptidoglycan
Peptidoglycan - structural
polysaccharides
(sugars) cross-linked by
peptides (chains of amino
acids)

12. The Gram stain procedure
Developed in 1884 by the Danish physician
Hans Christian Gram
An important tool in bacterial taxonomy,
distinguishing so-called Gram-positive
bacteria, which remain coloured after the
staining procedure, from Gram-negative
bacteria, which do not retain dye and need to
be counter-stained.
Can be applied to pure cultures of bacteria
or to clinical specimens
Top: Pure culture of E. coli
(Gram-negative rods)
Bottom: Neisseria gonorrhoeae in a smear of urethral pus
(Gram-negative cocci, with pus cells)

13. Crystal
violet
Gram's
iodine
Decolorise with
acetone
Counterstain with
e.g. methyl red
Gram-positives
appear purple
Gram-negatives
appear pink
The Gram Stain

14. Gram-positive rods
Gram-negative rods
Gram-positive cocci
Gram-negative cocci

15. Gram stain
Distinguishes different cell wall types
Gram positive Staphylococcus aureus
Gram negative Escherichia coli

16. 16
Be able to identify all the parts of
a Gram + & - cell wall for the next exam.

17. Two biochemical groups of bacteria:
peptidoglycan
outer
membrane

18. will stain will not stain
Gram positive bacteria Gram negative bacteria
Two biochemical groups of bacteria:
peptidoglycan
outer
membrane

19. Bacteria with Chemically Unique Cell Walls
 Acid-Fast Cells
 Mycobacterium species
 Gram + type of cell wall
 Unique lipid
 Mycolic acid – waxy substance
 Does not decolorize

20. Bacterial Growth
 Solid media or liquid media
 Agar plates, slopes, broth culture
 Atmosphere:
 Aerobic, anaerobic or microaerophilic
 Facultative or obligate anaerobes
 Usually at 37 degrees C
 Most clinically important bacteria grow overnight, or
within a few days
 Mycobacteria can take months
 Some can not be grown

21. Capsules or slime layer
E.g., slime layer
allows bacteria to
cling to tooth
enamel or other
substrates

22. Pili (singular: pilus)
Protein filaments that attach bacteria to other cells
& substrates
pili

23. Used for locomotion
Some prokaryotes have flagella
(singular: flagellum)
flagella

24. 50 nm
Base of a bacterial flagellum…
…the only known wheel in nature

25. Reproduction: Asexual, through binary fission
E. coli
DNA
cell wall

26. Binary fission
Daughter cells are identical copies
(1) (2) (3)
(4) (5) (6)
Chromosome Plasma membrane
Neither mitosis nor meiosis occurs in prokaryotes

27. REPRODUCTION
 Asexual, through binary fission
 No true sexual reproduction, since neither
mitosis nor meiosis exist in prokaryotes
 Horizontal transfer of genetic material
 Transformation Uptake of genetic material from the
environment
 Transduction Transfer of genetic material between
prokaryotes by viruses
 Conjugation Direct transfer of genetic material from one
prokaryote to another

28. Conjugation in E. coli
Sex pilus
Sex pilus connects cells and draws them together
Conjugation tube then forms

29. Bacteria
 Surviving harsh conditions
 Endospore – forms inside a bacterium and then persists
through inhospitable conditions
endospore

31. The oldest known fossils
First organisms
on Earth
Cyanobacteria
> 3 billion years
old

32. Distributed globally – including many
extremophiles
 “Heat-loving”
Archaea
 “Salt-loving”
Archaea

33.  Methanogens
Methane-generating Archaea
Occur in oxygen-free habitats
E.g., swamp mud, guts of
ruminant animals
 Cave Bacteria
 Sometimes reaching
acidity of pH 0.5
Distributed globally – including many
extremophiles

34. Ice Bacteria & Archaea
Distributed globally – including many
extremophiles

35. Prokaryote Nutrition – autotrophs & heterotrophs
All organisms require a source of
energy & carbon
Autotrophs can
obtain all their
C from CO2

36. All organisms require a source of
energy & carbon
Heterotrophs
require at least
one organic
nutrient, e.g.,
glucose
Prokaryote Nutrition – autotrophs & heterotrophs

37. All organisms require a source of
energy & carbon
Phototrophs
obtain their
energy from
the sun
Prokaryote Nutrition – autotrophs & heterotrophs

38. All organisms require a source of
energy & carbon
Chemotrophs
obtain their
energy from
chemical
compounds
Prokaryote Nutrition – autotrophs & heterotrophs

39. KLASIFIKASI BAKTERI