CLASSIFICATION OF BACTERIA BASED ON SHAPE Dr K

CLASSIFICATION OF BACTERIA BASED ON SHAPE Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 1

Bacteria is classified into different types based on their shape Ø Cocci Ø Bacilli Ø Vibrios Ø Spirilla Ø Spirochetes Ø Actinomycetes Ø Mycoplasmas Source: https: //www. quora. com/What-are-the-various-shapes-of-bacteria Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 2

Cocci cont’d Ø Cocci is derived from kokkos meaning berry in Greek Ø Spherical / Oval cells Ø Mostly spherical and sometimes elongated oval in shape Ø Diameter ranges from 0. 5 to 1. 0 micrometers. Ø Flat, elongated and oval-shape allows them to have a larger surface area, which allows the bacteria to easily absorb more amount of nutrients. Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 3

Cocci Ø Cocci is derived from kokkos meaning berry in Greek Ø Spherical / Oval cells Ø Mostly spherical and sometimes elongated oval in shape Ø Diameter ranges from 0. 5 to 1. 0 micrometers. Ø Flat, elongated and oval-shape allows them to have a larger surface area, which allows the bacteria to easily absorb more amount of nutrients. Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 4

Coccus These bacteria are spherical /oval in shape They are further sub divided into different types based on their arrangement i) Diplococcus: Coccus in pair. Eg, Neissseria gonorrhoae, Pneumococcus ii) Streptococcus: Coccus in chain. Eg. Streptococcus salivarius iii) Staphylococcus: Coccus in bunch. Eg. Staphylococcus aureus iv) Tetrad: Coccus in group of four. v) Sarcina: Cocus in cubical arrangement of cell. Eg. Sporosarcin Source: https: //en. wikipedia. org/wiki/Bacillus_%28 shape%29 Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 5

Bacilli These are rod shaped bacteria They are further classified asi) Coccobacilli ii) Streptobacilli: chain of rod shape bacteria: iii) Comma shaped iv) Chinese letter shaped Source: https: //en. wikipedia. org/wiki/Bacillus_%28 shape%29 Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 6

Mycoplasma They are cell wall lacking bacteria Also known as PPLO (Pleuropneumonia like organism) Eg: Mycoplasma pneumoniae Source: http: //www. biologydiscussion. com/cell/mycoplas ma/mycoplasma-history-habitat-characters-andcell-structure/23800 Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 7

Spirochaetes: They are spiral shaped bacteria Source: http: //cronodon. com/Bio. Tech/Bacteria_motility 3. html Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 8

Rickettsiae and Chlamydiae They are obligate intracellular parasites resemble more closely to viruses than bacteria Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 9

Actinomycetes They have filamentous or branching structure They resemble more closely to fungi than bacteria Example: Streptomyces Dr. K. Thamaraiselvi, Dept. of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli – 620 024, Tamil Nadu, India 10