TCP Pilus Expression and Biogenesis by Classical and El Tor Biotypes of Vibrio Cholerae 01

Abstract

The mechanisms utilized by Vibrio cholerae for adherence and colonization of the human intestine have remained elusive to investigators for many years. This is probably due to the overall complexity of colonization and the lack of genetic systems that allowed the introduction of defined mutations to eliminate the expression of individual components possibly involved in the process, thereby allowing for the assessment of each one’s role. The most likely molecules to mediate attachment include a number of bacterial cell surface and soluble hemagglutinins that vary with regards to the source of erythrocytes they hemagglutinate, the carbohydrate sensitivity of the binding, and the stage of growth during which they are expressed (1). The other potential mediators of colonization are several different pili (fimbriae), some of which may be the same as certain hemagglutinins, although this correlation has yet to be determined (3). The expression of these pili varies with growth conditions. One of these pili types, that we have recently reported on is shown in Fig. 1. We have named this pilus TCP for toxin coregulated pilus, because its expression parallels that of toxin production (12).