Computer identification of Escherichia coli rRNA gene restriction patterns.

摘要: A total of 191 strains Escherichia coli comprising 164 serovar reference and 28 clinical were characterized by rRNA gene restriction patterns (ribotypes) generated after cleavage DNA with Mlul, Clal or Hindlll endonucleases hybridization fragments acetylaminofluorene-labelled 16+23S rRNA. wide diversity ribotypes was observed Mlul (104 patterns), (90 patterns) (98 patterns). When used, 85% (11 to 15 fragments) shared five 17.09, 3.94, 3.06, 2.23 1.76 kb in size. these used as internal standards, the percent errors fragment length determination half that obtained an external standard. Two size databases built. Automatic identification setting variation tolerance (error) at 5%. Mlul ribotyping is recommended a primary epidemiological marker. Strains similar ribotype should then be submitted ribotyping. Ribotyping can only third choice, since often uncertain due frequent occurrence faint bands. Most studied serovars gave discrete data provide basis for molecular typing system E. which could possibly substitute serotyping when latter not available.