locomotion and reproduction in bacteria by Saira Mehar

Bacteriology

1. LOCOMOTION & REPRODUCTION IN BACTERIA Saira Mehar

2. Locomotion & Reproduction in Bacteria Locomotion . Flagellar motility Spirochaetal Movement Gliding Movement Reproduction . Vegetative reproduction Sexual reproduction Asexual reproduction

3. Locomotion 1) Flagellar Movement . Caused by flagella&cell surface appendages. Flagellum has typical structure(s ring or Stator&Basal body(hook) ).

4. M ring act like a Rotor(shaft). P&L act like a bearings or bushers. Basal body powered by proton energy-movement of ions b/w M&S ring.

5. Continued. Proton energy operates flagella into clockwise&anti-clockwise direction. Bacteria can swim smoothly,forward&reverse or Tumbling.

6. Peritrichously flagella move by Tumbling&anti-clockwise swimming. Polar flagella(mono,bi or multiple) are present.

7. Examples . salmonella. Vibrio. Spirillum. Azospirillum. Pseudomonas.

8. 1) Salmonella.

9. 2) Vibrio.

10. 3) Pseudomonas.

11. 4) Spirillum.

12. 5) Azospirillum .

13. 2. Spirochaetal Movement . Seen in`The Spirochetes’ of Bergey’s Manual of Determinative Bacteriology(group-5). Helical Bacteria. Flagella like axial filament burried outer&inner membrane of cell wall.

14. Axial filament composed of 2 or more fibrils. They perform flexing,swimming,creeping or swimming type of movement.

15. EXAMPLES Spirochaeta. Cristispira. Treponema. Borrelia. Leptospira .

16. 1) spirochaeta .

17. 2) Cristispira.

18. 3) Treponema.

19. 4) Borellia.

20. 5) Leptospira.

21. 3) Gliding Movement . Represented by `The Gliding Bacteria’ group(2) of Bergey’s Manual of Determinative Bacteriology. Do not have flagellar structures. Secrete slimy substances like SNAILS.

22. Gliding movement . Mechanism. Fimbriae like appendages at the poles of glider cell for locomotion. Generation of contractile waves. Surface tension. Pushing by secreted slime.

23. EXAMPLES . Cyanobacterium oscillatoria. C ytophaga . Polyangium. Cystobacter. Thioplaca. Archangium.

24. 1) Cyanobacterium Oscillatoria .

25. 2) Cytophaga .

26. 3) Polyangium .

27. Importance of Bacterial Locomotion. Chemotactic behavior and survival . Root colonization . Pathogenesis . Motile versus Non-motile .

28. Reproduction Process by which organism replicate themselves.

29. Types of reproduction: Asexual reproductin : Sexual reproduction: Vegetative reproduction:

30. Vegetative reproduction : Throug budding,fragmentation and Binary fissio n . 1) Budding : Bud develops at one end of cell. Replication of Genome. Budd enlarges,become daughter cell Finally gets Separated from parent cell.

31. Budding:

32. 2) Fragmentation : Through Gonidia> during unfavourable condition bacterial protoplasm undergo compartmentalization.

33. Under favourable condition bacterial genome replicate and formed new cell. Each gonidium grows to a new bacterium.

34. 3) Binnary Fission : Cell divides into two similar daughter cells. Bacterial chromosomes get attached to cell membrane,replicate to bacterial chromosome.

35. Cell enlarges>daughter chromosomes separate>cross wall formed>become two daughter cells. Daughter cell grow to maturity within 20-30 minutes during favourable condition.

36. Asexual reproduction : Takes place bye endospore formation .

37. Endospore formation  Resting spore>formed in some gram positive bacteria during unfavourable condition. Part of protoplast become concentrated arround chromosome. Hard resistance wall secreted arround it.

38. Rest of bacterial cell degenerates. Endospore are very resistance to extreme physical&chemical conditions.

39. During favourable condition>spore wall rupture>protoplasmic mass give rise to new bacterium

40. Endospore Formation :

41. 3) Sexual Reproduction: Occour in the form of Genetic Recombination . METHODS: Transformation. Transduction. Conjugation.

42. Transformation : Bacterial transformation first discovered by Griffith in 1928. the living cell picks up DNA that have been released by dead cells.Thus,the living cell gets additional DNA.

43. Transduction Fragments of DNA are carried from one bacterial cell to another by bacterial viruses . Types. Generalized transduction. Specialized transduction.

44.  ANY QUESTION? 

45. THANK YOU 