Bacterial disease

1. BACTERIA
CLS 311: Basic Microbiology
Mrs. Ohoud alhumaidan

2. OUTLINE
 History
 Prokaryote
 Introduction
 Bacteria size & shape ( Morphology + arrangement)
 Reproduction
 Classification
 Structure of bacterial cell
1. Capsule
2. Cell wall
3. Cell membrane ( cytoplasmic membrane)
4. Cytoplasm , chromosome and plasmid
5. Flagella
6. Pilli
7. Endospore

3. HISTORY
 Anton van Leeuwenhoek
 Louis Pasteur
 Robert Koch

4. MICROORGANISMS
A cellular
Cellular
Prokaryotes Eukaryotes
Archaea
Bacteria
Viruses
Protozoae
Fungi .

5. PROKARYOTES
 There are two major types of prokaryotes:
1. Bacteria.
2. Archaea (also called archaebacteria)

Prokaryotic cells possess simpler structures than eukaryotic cells ,

6. INTRODUCTION
 Bacteriology
 Bacteria (plural), Bacterium (singular).
 Binary fusion
 Generation time

7. BACTERIA SIZE & SHAPE
Size :
Ranging between 0.2m to 10.0 m in length
 Unit of microbial measurement is the micrometer (m), formerly micron ()
which is equal to:
1m = 1/1000 of a millimeter (mm)
Shape ( morphology )
1) Rods ( bacilli )
2) Cocci
3) Spiral or curved shape
4) pleomorphic

8. BACTERIAL MORPHOLOGY
 1- Shape:
 Bacilli (bacillus, singular)
– rod shaped organisms
 Cocci (coccus, singular) –
spherical or round
organisms
 Spirilla (spirillum,
singular) – spiralled or
comma-shaped
organisms

9. BACTERIAL MORPHOLOGY
 2-Arrangement : A- cocci

10. BACTERIAL MORPHOLOGY
 2-Arrangement : B- bacilli

12. REPRODUCTION
 Binary fission
 Two factors that affect bacterial
arrangements:
• Plane of division
• Position taken after cell division

13. REPRODUCTION

14. Cocci arrangement Example
diplococci Neisseria gonorrhea
Chains Streptococci,
Grapelike clusters Staphylococci
Groups of four (tetrads ) Peptococcu
Packets of eight Sarcinae

16. CLASSIFICATION

17. Kingdom Bacteria
Phylum Proteobacteria
Class Gamma Proteobacteria
Order Enterobacteriales
Family Enterobacteriaceae
Genus Escherichia
Species Escherichia coli
e.g. Escherichia coli

19. STRUCTURE OF BACTERIAL CELL
( CHECK CHAPTER 3)
 Cell Envelope :
Made up of two to three layers:
1. Cell wall .
2. Cell membrane .
3. Capsule : (in some species of bacteria )

20. STRUCTURE OF BACTERIAL CELL

21. 1- CAPSULE
 Made of polysaccharide
 Can be detected by capsule staining (
negative stain )
 Function of bacterial capsule

22. 2- CELL WALL
 cell wall provides strength , rigidity and protection
 Peptidoglycan
 Classification of bacteria according to cell wall :
1- have cell wall : Gram positive & Gram negative
2- lack of cell wall : e.g. : Mycoplasma ( AFB )

23. PEPTIDOGLYCAN

24. Gram stain

25. DIFFERENCES BETWEEN G+ & G -- (CHECK TABLE 4-5 ( CHAPTER 4)
 Gram positive  Gram negative

26. DIFFERENCES BETWEEN G+ & G- CELL WALL
FIGURE 3-8 (CHAPTER 4)

27. 3-CELL MEMBRANE

28. CYTOPLASM & CHROMOSOME & PLASMID
 Cytoplasm:
It is a gel-like matrix composed of water, enzymes,
nutrients, wastes, and gases .
 Chromosome :
bacterial cells possess only one chromosome .
 Plasmid :
Plasmids are small extrachromosomal genetic structures carried
by many strains of bacteria.
Like the chromosome, plasmids are made of a circular piece of
DNA. Unlike the chromosome, they are not involved in
reproduction.

29. FLAGELLA
 Flagella (singular, flagellum) are long hair-like
structures that can be found at either or both ends of
a bacterium or all over its surface.
 Function of the Flagella

30. PILLI
 Many species of bacteria have pili (singular, pilus),
short hair-like structures emerging from all around
the outside cell surface.
 Type of Pilli :
 Function of the Pilli :

31. ENDOSPORES
 Bacterial spores called endospore
 Sporulation
 Eg ; clostredium , Bacillus
 Function of endospores

32.  Several species of endospore-formers can
cause a disease :
 clostridium botulinum>> botulism
 Clostridium tetani >> tetanus
 Clostridiun prefrenges >>gas gangren