Charcteristics feature of E.coli

Charcteristics feature of E.coli :-

• This bacteria was discovered by a German scientist Eschrisch  from region of intestine , hence called Escherichia coli (E.Coli)
• It is bacillus from of bacteria and is reported in colon region of intestine of warm –blooded animal including human being .it is 1-3 (Meu ) in length and 0..4-0.7 (meu ) in diameter
• It is gram negative bacterium .slime layer or capsule is present in some strains of E.coli
• E.coli is a peritrichous bacterium i.e; flagella are present all over the surface of bacterium  further , pilli are also present are also present on surface , including sex-pilli ,which form conjugation tube during conjugation
• It is facultative anaerobic , bacterium & Optimum temperature  for  it is about 37 degree C, although it lives between 10-40 degree C.
• There are 1-4 circular DNA molecule in E.coli . there are about 3000 genes in E.coli .DNA in E.coli is double stranded , circular with estimated length of 1000 (Meu)
• Chemically E.coli has about 70% H2O , 15% proteins, 6% RNA , 1% DNA, 2% Lipids, 3% Craboydrates etc.
• Conjugation as a method of genetic recombination occur E.coli which was reported by Lederberg & Tatnum (1946)
• E.coli is important research material due to it short , life cycle, haploid nature & genetic recombinations. The mechanism of gene action & protein synthesis has been studied in it, beside regulation of protein synthesis (Operon model) has been studied in E.coli  by Jacob & Monod (1961)