The Anabaena sensory rhodopsin transducer defines a novel superfamily of prokaryotic small-molecule binding domains.

ABSTRACT: The Anabaena sensory rhodopsin transducer (ASRT) is a small protein that has been claimed to function as a signaling molecule downstream of the cyanobacterial sensory rhodopsin. However, orthologs of ASRT have been detected in several bacteria that lack rhodopsin, raising questions about the generality of this function. Using sequence profile searches we show that ASRT defines a novel superfamily of beta-sandwich fold domains. Through contextual inference based on domain architectures and predicted operons and structural analysis we present strong evidence that these domains bind small molecules, most probably sugars. We propose that the intracellular versions like ASRT probably participate as sensors that regulate a diverse range of sugar metabolism operons or even the light sensory behav

SUBMITTER: De Souza RF 

PROVIDER: S-EPMC2739507 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature