Conservation of the C-type lectin fold for massive sequence variation in a Treponema diversity-generating retroelement.

ABSTRACT: Anticipatory ligand binding through massive protein sequence variation is rare in biological systems, having been observed only in the vertebrate adaptive immune response and in a phage diversity-generating retroelement (DGR). Earlier work has demonstrated that the prototypical DGR variable protein, major tropism determinant (Mtd), meets the demands of anticipatory ligand binding by novel means through the C-type lectin (CLec) fold. However, because of the low sequence identity among DGR variable proteins, it has remained unclear whether the CLec fold is a general solution for DGRs. We have addressed this problem by determining the structure of a second DGR variable protein, TvpA, from the pathogenic oral spirochete Treponema denticola. Despite its weak sequence identity to Mtd (∼16%), Tvp

SUBMITTER: Le Coq J 

PROVIDER: S-EPMC3167528 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature