Molecular characterization of the autotransport process of Yersinia adhesin A (YadA)

Adhesins are surface structures of bacteria that facilitate their attachment to host cells or non-living materials. Most adhesins do not just bind to any surface; rather, they recognize specific molecules or receptors on the target surface. This recognition mechanism ensures that the bacteria infect a particular host species and within the host it infects a particular cell or tissue type. Thus, adhesins are one of the important virulence factors of bacteria. Yersinia Adhesin A (YadA) is one of the key virulence factors of Yersinia enterocolitica and Yersinia pseudotuberculosis. These two species of Yersinia are human pathogens and they cause a disease known as Yersiniosis. The symptoms of the disease include fever, abdominal pain (often confused with appendicitis), bloody diarrhea, and in some cases septicemia ("blood poisioning") or acute arthritis. Apart from its adherence function, YadA plays a role in preventing killing of the bacteria by immune system of the host and in biofilm formation (clumping of bacterial cells) which is a strategy of bacterial survival in the host.