1. Kharkov National Medical University
Head of Microbiology, Virology and Immunology Department
Minukhin Valeriy Vladimirivich

2. Tkachenko Victoria
1, 5, 11, 14, 19, 21, 30
Kovalenko Natalia
2, 12, 25, 29
Siritsa Anna
6, 8, 15, 16, 20, 22, 28
Kon Katerina
3, 7, 10, 18, 24, 26, 27
Mozgovaya Yulia
4, 9, 13, 17, 23

3. INTRODUCTION IN MEDICAL MICROBIOLOGY
Classification of microorganisms
Morphology of bacteria
Bacterial anatomy
Morphology of viruses
Morphology of rickettsiae
Morphology of chlamidia
Methods of laboratory diagnosis

4. Medical microbiology is the study of causative agents of infectious diseases of humans and their reactions to such infections. In other words it deals with etiology, pathogenesis, laboratory diagnosis, specific treatment and control of infection (immunization).

5. Modern medical microbiology
Bacteriology – the science of bacteria, the causative agents of a member of infectious diseases.
Virology – the science of viruses, non-cellular living systems, capable of causing infectious diseases in man.
Immunology – the science which concerned with mechanisms of body protection against pathogenic microorganisms and foreign cells and substances.
Mycology – the study of fungi pathogenic for man.
Protozoology – which deals with pathogenic unicellular animal organisms.

6. CLASSIFICATION OF MICROORGANISMS
Protista Vira
DNA-viruses and RNA-viruses
Eukaryotes Prokaryotes
Fungi Blue-green algae
Algae Bacteria
Protozoa Scotobacteria Photobacteria
Slime moulds Class Bacteria
2. Class Rickettsias
3. Class Mollicutes

7. Microbiological nomenclature
In microbiology the binominal system of nomenclature is accepted where each species has a generic and a specific name. The generic name is written with a capital letter, and the specific name – with a small letter. For example: the anthrax bacillus – Bacillus anthracis; the tetanus bacillus – Clostridium tetani.

8. The size of bacteria
The size of bacteria is measured in micrometer (m) or micron () (1 micron or micrometer is one thousandth of a millimeter) and varies from 0.1  to . Most pathogenic bacteria measure from 0.1 to 10 .
The other units of measurement of microorganisms are millimicron (m) or nanometer (nm) (one millionth of a millimeter) and 1 Angstrom (Å) (one tenth of nanometer).

9. Morphology of Bacteria
Bacteria are intracellular free-living organisms having both DNA and RNA. Their biological properties and predominant reproduction by binary fission relates them to prokaryotes.
Spherical (cocci)
Rod-shaped
(bacteria, bacilli,
and clostridia)
Spiral-shaped
(vibriones, spirilla, spirochaetes)

10. Spherical (cocci) bacteria
Micrococci
Diplococci
Streptococci
Staphylococci
Tetracocci
Sarcine

11. Representatives of pathogenic cocci1 2
1.Scanning Electron Micrograph of Streptococcus pneumoniae
2.Scanning electron micrograph of a Staphylococcus aureus

12. Electron Micrograph of Neisseria gonorrhoeae

13. Rod-shaped bacteria 1
Bacteria (1) include those microorganisms, which, as rule, do not produce spores (E.coli, Salmonella, Shigella).
Bacilli (2) (B.anthracis) and clostridia (3) (C.tetani, C.botuli-num) include organisms the majority of which produce spores.
Size of rod-shaped bacteria varies 2-10 μm: small rods are 2-4 μm; long rods are 5-10 μm. 2 3

14. ARRANGEMENT OF ROD-SHAPED BACTERIA

15. Rod-shaped bacteria 1 2
Single Rod
Streptobacillus

16. SPIRAL FORMS
1. Vibrios – are cells, which resemble a comma in appearance (curved rods). Typical representative of this group is Vibrio cholerae.

17. 2. Spirilla – are coiled forms of bacteria
2. Spirilla – are coiled forms of bacteria. Pathogenic species: Spirillum minus (1) – which is responsible for a disease in humans transmitted through the bite of rats – rat-bite fever – sodoku; Helicobacter pylori (2) – causative agent of ulcer disease of stomach. 2 1

18. SPIROCHAETES
Treponema – exhibits, thin, flexible cells with 6-14 regular twists. The size of Treponema varies from μ (T.pallidum).
Leptospira – are characterized by very thin cell structure. The leptospirae form regular coils (primary spirals) (L.interrogans) and C- or S- shape according secondary twist.
Borrelia – have large irregular spirals, the number of which varies from 3 to 10. (B.recurrentis, B.persica).

19. 3. Spirochaetes – are flexuous spiral forms which include: Treponema (T.pallidum) (1), Borrelia (B.recurrentis) (2), Leptospira (L.interrogans) (3) 1 3 2

20. BACTERIAL CELL

21. FLAGELLA
Electron Micrograph of Bacteria with Flagella

22. CAPSULE
Enterobacter aerogenes
Klebsiella pneumoniae

23. SPORE
Bacillus anthracis
Bacillus megaterium

24. Cell wall
In addition to conferring rigidity upon bacteria, the cell wall protects against osmotic damage
Chemically, the rigid part of the cell wall is peptidoglycan
First described by Gram in It is' used to study morphologic appearance of bacteria. Gram's stain differentiates all bacteria into two distinct groups:
a. Gram-positive organisms
b. Gram-negative organisms

25. fuchsine
Gram
Staining
Technique

27. Bacteria with deficient cell walls
Mycoplasma: a genus of naturally occurring bacteria which lack cell walls
L-forms: cell-wall-deficient forms of bacteria, usually produced in the body of patients treated with penicillin
Spheroplasts: derived from Gram-negative bacteria; produced artificially by lysozyme or by growth with penicillin or any other agent capable of breaking down the peptidoglycan layer
Protoplasts: derived from Gram-positive bacteria and totally lacking cell walls; produced artificially by lysozyme and hypertonic medium

28. Electron micrograph mycoplasma cells (1) and L-forms of Proteus mirabilis (2)

29. Morphology of viruses Do not possess cellular organization
Contain one type of nucleic acid either RNA or DNA
Lack enzymes necessary for protein and nucleic acid synthesis machinery of host cells
They multiply by complex process and not by binary fission.
They are unaffected by antibiotics.
They are sensitive to interferon.

31. Morphology of viruses

32. Morphology of Rickettsiae.
They are minute organisms having properties in between bacteria and viruses.
It contains both DNA and RNA.
Contains enzymes for metabolic functions.
Multiplies by binary fission.
It is coccobacilli 300x600 nm in size, non-motile, non-capsulated and is Gram-negative.
Sensitive to many antibiotics.
Can multiply only inside living cells.

33. Morphology of Rickettsiae

34. Morphology of chlamydia.
Chlamydiae are Gram-negative. They lack some important mechanisms for the production of metabolic energy, so they are intracellular parasites. There are 2 morphological forms of chlamydia:
Elementary bodies
Initial bodies

35. Methods of laboratory diagnosis
Bacterioscopical
Bacteriological
Detection sensitivity of bacteria to antibiotics
Serological
Biological
DNA-technology test (PCR)