MIKROBIOLOGI

1. Textbook Reading
Supervisor:
dr. A. R. Sultan, DMM., M.Sc., Ph.D., Sp.M.K.
CLINICAL MICROBIOLOGIST IN TRAINING FACULTY OF MEDICINE
HASANUDDIN UNIVERSITY MAKASSAR
2023
Lalu Yan Hidayat
C195222004
TEXTBOOK READING
Pathogenesis of infectious diseases

2. INTRODUCTION
• How bacteria causes disease to human being  Pathogenesis.
• Pathogenesis is a multi-factorial process
• Immune status
• Nature of the species or strain

3. Normal Flora
Environment Bacteria

4. Postulate Koch
https://courses.lumenlearning.com/suny-microbiology/chapter/how-pathogens-cause-disease/
Identification bacteria cause
disease
Ex : Treponema Pallidum and Mycobacterium
leprae not criteria Postulate Koch

5. PATHOGENESIS
Pathogenesis is the capacity to initiate disease.
1. Transmissibility
2. Survival
3. Infectivity
4. Virulence
5. Complex bacterial-host relationship
https://microbenotes.com/factors-affecting-bacterial-pathogenicity/ https://microbiologynotes.org/overview-of-the-bacterial-pathogenesis/

6. Types of bacterial pathogens
- Primary pathogens are capable of
establishing infection and causing
disease in previously healthy individuals
with intact immunological defenses
- Opportunistic pathogens rarely cause
disease in individuals’ with intact
immunological and anatomical defenses
https://link.springer.com/chapter/10.1007/978-1-4939-7349-1_14

7. Steps Involved in The Pathogenesis of The Bacteria
TRANSMISSION BACTERIA
Potential pathogens may enter the
body by various routes, including
the respiratory, gastrointestinal,
urinary or genital tracts.
https://journals.asm.org/doi/10.1128/microbiolspec.mtbp-0019-2016
- Salmonella and Campylobacter animals  foodhuman
- Y. Pestis rodent fleas human
- Bacillus anthracis (anthrax) environtmentanimalshuman
- Clostridium spp  environtment

8. ADHESION BACTERIA
https://www.mdpi.com/1422-0067/16/2/2626 How Bacterial Adhesins Affect Host Signaling and What We Can Learn from Them

10. INVASION BACTERIA
https://www.frontiersin.org/articles/10.3389/fmicb.2020.00563/full

11. COLONIZATION BACTERIA
The establishment of a stable
population of bacteria on the host’s
skin or mucous
membranes is called colonization.
Microbiology Lippincott 3 rd

12. TOXIN
Exotoxins Many bacteria produce proteins (exotoxins) that modify, by enzymatic action, or
otherwise destroy certain cellular structures.
Endotoxins are toxic components of the bacterial cell envelope. The classical and most potent
endotoxin is lipopolysaccharide.
https://microbiologyinfo.com/differences-between-exotoxins-and-endotoxins/

13. Mechanism endotoxin and exotoxin
https://www.labtestsguide.com/differences-between-exotoxins-and-endotoxins-2

14. EXOTOXIN
Classes of exotoxin :
1. superantigens (Type I toxins);
https://www.mdpi.com/2072-6651/12/3/176

15. 2. A-B toxins and other toxin that interfere with host
cell function (Type III toxins)
1. Bacterium produces and releases the A-B toxin
2. B (binding) component of the exotoxin attaches the host cell receptor.
3. The plasma membrane of the host cell invaginates (holds inward) at the
point where the A-B exotoxin and plasma receptor make contact. The
exotoxin enters the cell by receptor-mediated endocytosis.
4. A-B exotoxin and receptor are enclosed in pinched-off portion of plasma
membrane during pinocytosis.
5. A-B components of exotoxin separate. The A component alters host cell
function, often by inhibiting protein synthesis. The B component is
released fro the host cell, and the receptor is inserted into the plasma
membrane for reuse.

16. ENDOTOXIN

18. ENZYME
1. Tissue-Degrading Enzymes
C. perfingens  collagenase
S. aureus produces coagulase
Hyaluronidases
streptokinase (fibrinolysin)
Cytolysins
Streptolysin O
Streptolysin O
1. Tissue-Degrading Enzymes
C. perfingens  collagenase
S. aureus produces coagulase
Hyaluronidases
streptokinase (fibrinolysin)
Cytolysins
Streptolysin O
Streptolysin O
1. Tissue-Degrading Enzymes
C. perfingens  collagenase
S. aureus produces coagulase
Hyaluronidases
streptokinase (fibrinolysin)
Cytolysins
Streptolysin O
Streptolysin O