CORRELATION BETWEEN ESTERASE ELECTROPHORETIC POLYMORPHISM AND VIRULENCE-ASSOCIATED TRAILS IN EXTRAINTESTINAL INVASIVE STRAINS OF ESCHERICHIA-COLI

The electrophoretic variations of carboxylesterase B and of esterases A, C and I, the presence of mannose resistant haemagglutinin, alpha-ha emolysin, cytotoxic necrotizing factor type 1 (CNF1) and certain 0 ant igens were compared in 150 strains of Escherichia coli responsible for extra-intestinal infections. Electrophoretic mobilities of outer memb rane proteins (OMP) were also studied for strains belonging to 04, O6, 07, 08 and 075 serogroups. Past migrating allozymes of carboxylestera se B (pattern B-1) were correlated with slow migrating allozymes of es terase C, serogroups 07 and 08, lack of virulence factor, and particul ar OMP patterns, whereas slow migrating allozymes of carboxylesterase B (pattern B-2) were correlated with fast migrating allozymes of ester ase C, serogroups 02, 04, 06, 018 and 075, virulence factor production , and distinct OMP patterns. Allozymes of esterases A and I were not c learly correlated with the distribution of virulence factors. The patt ern B-2 was more strongly associated with CNF1 than with alpha-haemoly sin and mannose resistant haemagglutinin. These results substantiate t he view that the electrophoretic pattern B-2 of carboxylesterase B ide ntified most of the highly pathogenic strains implicated in extra-inte stinal infection of humans.