PilB from <i>Streptococcus sanguinis</i> is a bimodular type IV pilin with a direct role in adhesion.

ABSTRACT: Type IV pili (T4P) are functionally versatile filamentous nanomachines, nearly ubiquitous in prokaryotes. They are predominantly polymers of one major pilin but also contain minor pilins whose functions are often poorly defined and likely to be diverse. Here, we show that the minor pilin PilB from the T4P of Streptococcus sanguinis displays an unusual bimodular three-dimensional structure with a bulky von Willebrand factor A-like (vWA) module "grafted" onto a small pilin module via a short loop. Structural modeling suggests that PilB is only compatible with a localization at the tip of T4P. By performing a detailed functional analysis, we found that 1) the vWA module contains a canonical metal ion-dependent adhesion site, preferentially binding Mg²⁺ and Mn²⁺, 2

SUBMITTER: Raynaud C 

PROVIDER: S-EPMC8179133 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature