Several archaeal homologs of putative oligopeptide-binding proteins encoded by Thermotoga maritima bind sugars.

ABSTRACT: The hyperthermophilic bacterium Thermotoga maritima has shared many genes with archaea through horizontal gene transfer. Several of these encode putative oligopeptide ATP binding cassette (ABC) transporters. We sought to test the hypothesis that these transporters actually transport sugars by measuring the substrate affinities of their encoded substrate-binding proteins (SBPs). This information will increase our understanding of the selective pressures that allowed this organism to retain these archaeal homologs. By measuring changes in intrinsic fluorescence of these SBPs in response to exposure to various sugars, we found that five of the eight proteins examined bind to sugars. We could not identify the ligands of the SBPs TM0460, TM1150, and TM1199. The ligands for the archaeal SBPs are

SUBMITTER: Nanavati DM 

PROVIDER: S-EPMC1392961 | biostudies-literature | 2006 Feb

REPOSITORIES: biostudies-literature