Expanding the type IIB DNA topoisomerase family: identification of new topoisomerase and topoisomerase-like proteins in mobile genetic elements.

ABSTRACT: The control of DNA topology by DNA topoisomerases is essential for virtually all DNA transactions in the cell. These enzymes, present in every organism, exist as several non-homologous families. We previously identified a small group of atypical type IIB topoisomerases, called Topo VIII, mainly encoded by plasmids. Here, taking advantage of the rapid expansion of sequence databases, we identified new putative Topo VIII homologs. Our analyses confirm the exclusivity of the corresponding genes to mobile genetic elements (MGE) and extend their distribution to nine different bacterial phyla and one archaeal superphylum. Notably, we discovered another subfamily of topoisomerases, dubbed 'Mini-A', including distant homologs of type IIB topoisomerases and encoded by extrachromosomal and integrate

SUBMITTER: Takahashi TS 

PROVIDER: S-EPMC7671362 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature