The reverse gyrase helicase-like domain is a nucleotide-dependent switch that is attenuated by the topoisomerase domain.

ABSTRACT: Reverse gyrase is a topoisomerase that introduces positive supercoils into DNA in an ATP-dependent manner. It is unique to hyperthermophilic archaea and eubacteria, and has been proposed to protect their DNA from damage at high temperatures. Cooperation between its N-terminal helicase-like and the C-terminal topoisomerase domain is required for positive supercoiling, but the precise role of the helicase-like domain is currently unknown. Here, the characterization of the isolated helicase-like domain from Thermotoga maritima reverse gyrase is presented. We show that the helicase-like domain contains all determinants for nucleotide binding and ATP hydrolysis. Its intrinsic ATP hydrolysis is significantly stimulated by ssDNA, dsDNA and plasmid DNA. During the nucleotide cycle, the helicase-li

SUBMITTER: del Toro Duany Y 

PROVIDER: S-EPMC2566858 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature