English: Transmission electron microsope image of Vibrio choleraethat has been negatively stained. Vibrio choleraeis the bacteria responsible for the gastroinestinal disease cholera. In order to get the disease cholera, the bacteria must be able to colonize in the small intestine and a critical factor necessary for this colonization is the toxin-co-regulated pilus(TCP). 0395 is a wild type strain, showing the normal bundling of toxin-co-regulated pilus(TCP). Wild-type pili are clearly visible as 7 nm fibres that form bundles @ 0.2Ð0.3 µm wide and 3Ð6 µm long.