Antigenic Changes in Shigella flexneri Following Conjugation with Escherichia coli HfrC

Publisher Website
Google Scholar
Abstract
The biosynthesis of Shigella flexneri O‐antigens proceeds through the rough precursor antigens to the (group antigen) variant Y form under the influence of bacterial chromosomal genes. Type specificity is then conferred on the growing molecule with the incorporation of terminal α‐glucosyl secondary side chains by specific UDP‐glucose transferases under the control of the appropriate prophage(s) at the type specific or T‐locus. When the various Sh. flexneri serotypes are conjugated with Escherichia coli HfrC, the T‐locus with its phage attachment site(s) is lost so that antigen biosynthesis stops at the end of the chromosomal or variant Y stage. These findings offer an explanation for the observation that many Sh. flexneri x E. coli HfrC hybrids carry Y‐specificity.