Diversity of bacteria

diversity of the bacteria can be classified based on cell shape,gram stain and position of flagella.

Cell shape

The classification of the bacteria can be done by their shape.

• coccus: spherical shape
• bacillus: rod shape
• spirillum: have one or more twist
• vibrious: comma shape

Gram stain

1.Gram positive
-stain blue or violet
-simple cell walls with a lots of polipeptidoglycan
-purple or blue stain is trapped in cell wall
-less threatening pathogens
-eg: bacillus,clostridium,staphylococcus and streptococcus

2.gram negative
-more complex cell wall with less peptidoglycan
-blue dye wash out
-outer membrane cover cell wall
-more pathogenic
-lipopolysaccharides in outer membrane often toxic
-eg: salmonella,E.coli and azotobacteria





Position of flagella

the position of flagela can determine the classification of bacteria

1. peritrichous: the falgella grow around the body
2. monoatrichous: only one flagela
3. amphitrichous:have 2 flagella
4. atrichous: have no flagella
5. cephalotrichous: have flagella at only at one side
6. lopotrichous: have flagella grow on both ends

Importance

(a) Recycling chemical element in ecosystem
-control breakdown of plant and animal
- recyling orcarbon,phosporus and nitrogen fixation

(b) symbiotic relationship
-Enterobacteria eg: E.coli io human intestine

(c) pathogenic
-plant pathogenic bacteria
-agent of disease

(d) In research and technology
-manufacturing process: making soap powder,tanning leather
-medical research: easily cultured,making antibiotic,amino acid and enzyme