Anaerobic metabolism of primary and secondary forms of Photorhabdus luminescens

Abstract A Vibrio cholerae O1 strain (1150) of the EITor biotype and Ogawa serotype with haemagglutination (HA) activity was subjected to TnphoA mutagenesis. Out of several mutants isolated, one HA⁻ and another HA⁺ mutant were further characterised. The HA⁻ mutant showed about 50% reduction in its intestinal adherence capacity in vitro and about 9-fold decrease of its colonisation ability in vivo, as compared to the wild-type strain. Subsequent studies showed that the HA activity of strain 1150 was mediated by a mannose-sensitive haemagglutinin (MSHA). Thus, the phenotypic expression of MSHA appears to be partly responsible for the intestinal adherence and colonisation properties of strain 1150.