STRUCTURE OF BACTERIA AND ITS METABOLISM

This presentation creates a structure of bacteria, shapes of bacteria, metabolism and respiration process

1. BACTERIA

2. TYPHOID FEVER

3. MILESTONES IN BACTERIOLOGY 1829 C.G. Ehrenberg coined the term Bacterium

4. Bacteria were first discovered by a Dutch scientist, Anton van Leeuwenhoek in 1676 and were called “animalcules”.

5. Prokaryotes Genetic material – nucleoid/ Genophore /incipient nucleus Cellwall - peptidoglycan and proteins Lack chlorophyll- heterotrophic Autotrophic – Bacteriochlorophyll( chromatium ) Reproduction – binary fission and endospore formation genetic recombination - variation Conjugation, transformation and transduction

6. A thick layer of  glycocalyx  bound tightly to the cell wall is called  capsule . It protects cell from desiccation and antibiotics. It helps to retain the nutrients in bacterial cell.

7. granular and is rigid. provide protection and gives shape to the cell.  Peptidoglycan and mucopolypeptide and 4to 5 aminoacid chain Porin –diffusion of solutes

8. Plasma membrane Entry & exit of molecules Oxidation of metabolites Photosystems in photosynthesis

9. glycogen, poly- β- hydroxybutyrate granules, sulphur granules and gas vesicles  ribosomes

10. Bacterial chromosome S ingle circular DNA molecule, tightly coiled and is not enclosed in a membrane as in Eukaryotes. This genetic material is called  Nucleoid or Genophore . DNA is not bound to  histone  proteins. The single chromosome   or the DNA molecule is circular and at one point it is attached to the plasma membrane  Help in separation of chromosomes after replication

11. Plasmids

12. PLASMIDS extra chromosomal double stranded, circular, self-replicating, autonomous elements. They contain genes for ­fertility, antibiotic resistant and heavy metals. It also help in the production of bacteriocins and toxins size of a plasmid  - 1 to 500 kb Plasmids are classified into different types based on the function. Some of them are F (Fertility) factor, R (Resistance)­ plasmids, Col (Colicin) plasmids, Ri (Root ­inducing) plasmids and Ti ( Tumour inducing) plasmids.

13. clumped and folded together to maximize their surface area helps in respiration and in binary fission.

14. 70S SITE FOR PROTEIN SYNTHESIS 10,000 TO 15,000 SUBUNITS

15. T hin hair like processes of variable length emerge from the cell wall called flagella. 20–30 μm in diameter and 15 μm in length. The flagella of Eukaryotic cells contain 9+2 microtubles but each flagellum in bacteria is made up of a single fibril. Flagella are used for locomotion. FLAGELLA

16. PILI OR FIMBRIAE hair like appendages found on surface of cell wall of gram-negative bacteria (Example:  Enterobacterium ). The pili are 0.2 to 20 µm   long with a diameter of about 0.025µm. special type of pili which help in conjugation called sex pili are also found.

17. GRAM STAINING PROCEDURE

18. B acteria require oxygen as terminal acceptor and will not grow under anaerobic conditions  Eg. Streptococcus B acteria do not use oxygen for growth and metabolism but obtain their energy from fermentation reactions. Eg :Clostridium

19. Obligate aerobes must have oxygen to survive Micrococcus   species  

20. FACULTATIVE ANAEROBES Bacteria that can grow ­either ­using oxygen as a terminal electron acceptor­ or anaerobically using fermentation reaction to obtain energy. E.coli – abdominal abscess – anaerobic condition – cause diseases Eg:E.coli and Salmonella.

21. Capnophilic bacteria Bacteria which require CO 2  for their growth  Eg : Campylobacter

22. Mycobacterium Bacillus mycoides

23.   Photolithotrophs and photo organotrophs   Chemolithotrophs and chemoorganotrophs

24. Photolithotrophs HYDROGEN SULPHIDE BACTERIOVIRIDIN Eg:CHLOROBIUM Thiosulphate bacteriochlorophyll Chlorosomes (chlorophyll) Eg : Chromatium

25. Eg : Hydrogenomonas Eg : Thiobacillusthioxidans Eg:Nitrosomonas and Nitrobacter

26. chemoorganotrophs Methanococcus

27. Reproduction in Bacteria

28. conidiospores