1. Medical Microbiology (Biology of Small Organisms)
Major Topics Included in MAC 221
Bacteriology
Virology
Parasitology
Mycology
Immunology

2. Introduction To Mac 221:
Basic Immunology and Host Parasite Relationship
Bacteria and Human Diseases caused by bacteria.
Parasitology Parasite & Human Diseases
Virology – Virus & Human Diseases
Mycology – Fungi & Human Diseases

3. Microbiology And The Patient
Medical Microbiology – concerned with:
Aetiology (cause)
Pathogenesis (Mechanism of production of disease)
Laboratory Diagnosis
Treatment of infection
Epidemiology (spread, distribution, prevalence of infection in the community)
Control and prevention in community

4. MIC has Close Link with:
Pathology
Medicine (clinical)
Surgery
Pharmacology and therapeutics
Preventive Medicine

5. MIC has a Close Link with Curative Medicine in regard to:
Precise diagnosis
Rational treatment of microbial diseases
Diagnosis of Bacterial infection done by:
Clinical
Laboratory Methods

6. Laboratory Methods: Collection of specimens
Microscopy Stained Specimens
Unstained Specimens
Culture
Identification of the organism
Tests for Antimicrobial agents serology
Demonstration of Abs

7. Medical Students Need to Know Microbiology Especially Bacteriology
To Diagnose
Bacterial infections successfully
2) To Treat

8. Course Objectives Basic understanding of immune system
2) Basic understanding of host-parasite relationship
3) Understandingof the pathogenesis
4) Understand the clinical features
5) Understand the Epidemiological features

9. Course Objectives (Continued)
6) Understand the proper use of Clinical Lab.
a) Specimen collection and handling
b) Requesting appropriate tests
c) Interpretation of results of Lab. tests
Correct selection, use, monitoring of anti-microbial therapy
Understand methods of prevention of infection e.g. Vaccine, chemoprophylaxis, hygiene, isolation etc.

10. Diagram of Atypical Bacterial Cell

11. Comparison Between Bacteria And Fungi And Protozoa
Unicellular, Microscopic, Prokaryotic Organisms, Multiply By Binary Fission.
Comparison Between Bacteria And Fungi And Protozoa
Bacteria Fungi & Protozoa
Type Prokaryotic Eukaryotic
Chromosome One Multiple
(Number)
Nuclear Absent Present
Membrane

12. Comparison Between Bacteria and Fungi and Protozoa (Continued)
Bacteria Fungi & Protozoa
Mitochondria Absent Present
Ribosomes 70s 80s
Sterols Absent (Except Usually In Mycoplasma) Present
Cell Wall Rigid Layer Of No Peptido-
Peptidoglycan Glycan (Absent In (In some cases
Mycoplasma) cellulose present)

13. Bacteria can be divided into:
Filamentous Bacteria (Actinomycete) Most capable of branching
True (Euobacteria): Divide by Binary Fission
Spirocheates: Divide by Transverse Binary Fission
Mycoplasma Which Lack Rigid Cell Wall
Ricketssiae, and Chlamydia which are strict Intracellular parasites
Cocci
Bacilli (rods)
Vibrio (coma shape)

14. Taxonomic Ranks Formal Rank Example Kingdom Prokaryotae
________________________________________________________________________________________________________________________
Kingdom Prokaryotae
Division Gracilicutes
Class Scotobacteria
Order Eubacteriales
Family Enterobacteriae
Genus Eschirichia, Streptococcus, Staphylococcus, Streptococcus, Klebsiella
Species coli Pyogenes aureus pneumoniae pneumonia

15. Arranged in Micrococcus
Simplified Classification of Medically – Important Gram-positive Bacteria
Arranged in Micrococcus
Aerobes or clusters
facultative Staphylococcus
Anaerobes
Cocci Arranged in Streptococcus
chains
Anaerobes
Peptostreptococcus

16. Simplified Classification of Medically – Important Gram-positive bacteria
Sporing Bacillus
Aerobes or facultative anaerobes Corynebacterium
Non- Listeria
sporing Lactobacillus
Nocardia
Mycobacterium
RODS
Sporing Clostridium
Anaerobes
Non Actinomycosces
sporing

17. Simplified Classification Of Medically – Important Gram-negative Bacteria
Aerobes Neisseria
Cocci
Anaerobes Veillonella

18. Simplified Classification Of Medically – Important Gram-negative Bacteria
Aerobes Pseudomonas
Salmonella
Shigella
Klebsiella
Proteus
Escherichia
Facultative Yersinia
Anaerobes
BACILLI Bordetella
Haemophilus
Brucella
Pasteurella
Vibrio
Anaerobes Bacteroids
Fusobacterium
Microaerophilic Camplylobacter

19. Simplified Classification Of Medically – Important Gram-negative Bacteria
Aerobes Leptospira
Spirochaetes
Anaerobes Borrelia
Treponema
Cell wall Mycoplasma
deficient bacteria

20. Diagram of Atypical Bacterial Cell

21. External Structures I) Flagella Long Filaments
a. Responsible for motility;
b. Protein (Flagellin) similar to myosin of muscles
c. Can be polar, Bipolar or Peritrichous
Short Filaments
a. Common pili Adhesion
b. Sex pili Conjugation

22. Capsule Present in Certain Bacteria.
Water (2 %) solid Polysaccharide; occasionally protein
e.g. Bacillus anthracis
a. Inhibit Phagocytosis
b. Antigenic

23. Example Of Capsulated Bacteria
a. Pneumococci
b. Klebsiella Polysaccharide Capsules
c. Cl. perfringens
d. Bacillus anthracis Polypeptide Capsules

24. Flagella

26. Bacterial Spores Hardest part of bacteria Contain calicum pectate
One spore = one negative bacteria
Can live for years
Example:
1. Clostidia (Anaerobic)
e.g. Cl. perfringens
2. Bacillus (Aerobic)
e.g. B. anthracis

27. a. Confer rigidity upon bacteria
CELL WALL - porous, permeable to low molecular weight (LMW) substances.
Found in Algae, fungi, plants and bacteria
Not found in animals
Functions Of Cell Wall
a. Confer rigidity upon bacteria
b. Protects against osmotic pressure which can be atmospheric pressure in bacteria
c. Gives bacteria its shape
d. Participates in cell division
e. Gram staining characteristic

28. Structures of Cell Wall
Basic = mucopeptide (peptidoglycan)
PEPTIDOGLYCAN = consists of
a. N-acetyl mumaric acid (M)
b. N-acetyl glucosamine (G) strands.
Theses strands are linked by peptide side chains
Peptide
chain G M M G G M

30. In Addition Gram +ve bacterial cell wall
a Thick peptidoglycan layer (many layers)
b. Teichoic acids (20% of cell wall weight)
Gram –ve cell wall
a. Thin peptidoglycan layer (1-2 layers)
b. Out layer of lipopolysaccharide, phospholipids, lipoprotein
c. Porins

31. Diagrams Showing The Structure Of Bacterial Cell Walls

35. Annual System Bacteriology + Immunology = 50% = 50 marks
Practical = 10 marks
Mid term = 10 marks
Final = 30 marks
Parasitology & Virology + Mycology
= 50% = 50 marks
Mid Term = 10 marks
Final Exam= 30 marks