Variation in genome size among strains

Range 2.3×10^9-3.0×10^9 Daltons
Organism Bacteria Escherichia coli
Reference Brenner DJ, Fanning GR, Steigerwalt AG, Orskov I, Orskov F. Polynucleotide sequence relatedness among three groups of pathogenic Escherichia coli strains. Infect Immun. 1972 Sep6(3):p.311 right column bottom paragraphPubMed ID4564889
Method Abstract: "Escherichia coli strains that cause dysentery-like disease, parenteral infection, and infantile diarrhea form specific groups based on mobility of O and K antigens in immunoelectrophoresis. Members from each of these groups were assayed for gross nucleotide sequence relatedness. The method used was interspecific deoxyribonucleic acid (DNA) reassociation reactions carried out free in solution. Reassociated DNA was separated from unreacted DNA by passage through hydroxyapatite."
Comments P.311 right column bottom paragraph: "Genome size variations from 2.3×10^9 daltons to 3.0×10^9 daltons exist among E. coli strains as shown by nonreciprocal binding in reciprocal reassociation reactions and by differences in initial rates of reassociation determined spectrophotometrically (refs 3, 4). Differences in genome size can account for what may appear to be abnormally high or low binding. For example, in reciprocal reactions, 91% of E. coli K-12 DNA is equivalent to 74% of DNA from E. coli strain 02A due to the larger genome size of 02A as compared to that of K-12." These values can be converted to number of bp: Multiplying by weight of Dalton, 1.66×10^-27kg. Multiplying by 10^15 to arrive at pg. Multiplying by 0.978×10^9 to get range of 3,734,004 to 4,870,440bp. For E.coli genome size of 4,600,000bp see BNID 100269
Entered by Uri M
ID 102544