Distinctive ligand-binding specificities of tandem PA14 biomass-sensory elements from Clostridium thermocellum and Clostridium clariflavum.

ABSTRACT: Cellulolytic clostridia use a highly efficient cellulosome system to degrade polysaccharides. To regulate genes encoding enzymes of the multi-enzyme cellulosome complex, certain clostridia contain alternative sigma I (σ^I ) factors that have cognate membrane-associated anti-σ^I factors (RsgIs) which act as polysaccharide sensors. In this work, we analyzed the structure-function relationship of the extracellular sensory elements of Clostridium (Ruminiclostridium) thermocellum and Clostridium clariflavum (RsgI3 and RsgI4, respectively). These elements were selected for comparison, as each comprised two tandem PA14-superfamily motifs. The X-ray structures of the PA14 modular dyads from the two bacterial species were determined, both of which showed a high degree of structu

SUBMITTER: Grinberg IR 

PROVIDER: S-EPMC6852018 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature