Comparative methodology to investigate the presence of Escherichia coli K-12 strains in environmental and human stool samples.
This study was undertaken to evaluate the specificity and efficiency of different methods to detect Escherichia coli K-12 strains. Another aim was to determine the frequency of E. coli K-12 strains among wild-type E. coli isolates from different sources. The detection of K-12 strains was performed both genotypically by K-12 specific polymerase chain reaction (PCR) and on the basis of phenotypical tests. In addition, the genome structures of E. coli strains were characterized by pulsed-field gel electrophoresis (PFGE). The most specific results could be obtained by the genotypical tests PCR and PFGE as well as by the K-12 specific phage assay. In total, 131 stool and 95 water isolates as well as 14 K-12 derivatives were examined by the different methods. No E. coli K-12 strains were detected among the wild-type isolates.
Blum
G
G
Institut für Molekulare Infektionsbiologie, Würzburg, Germany.
Mühldorfer
I
I
Kuhnert
P
P
Frey
J
J
Hacker
J
J
D001431:Bacteriological Techniques / Q000706:statistics & numerical data; D003090:Coliphages; D016521:Electrophoresis, Gel, Pulsed-Field; D004783:Environmental Microbiology; D004926:Escherichia coli / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology*; D005838:Genotype; D006801:Humans; D010641:Phenotype; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity