An array of basic residues is essential for the nucleolytic activity of the PHP domain of bacterial/archaeal PolX DNA polymerases.

ABSTRACT: Bacterial/archaeal family X DNA polymerases (PolXs) have a C-terminal PHP domain with an active site formed by nine histidines and aspartates that catalyzes 3'-5' exonuclease, AP-endonuclease, 3'-phosphodiesterase and 3'-phosphatase activities. Multiple sequence alignments have allowed us to identify additional highly conserved residues along the PHP domain of bacterial/archaeal PolXs that form an electropositive path to the catalytic site and whose potential role in the nucleolytic activities had not been established. Here, site directed mutagenesis at the corresponding Bacillus subtilis PolX (PolXBs) residues, Arg⁴⁶⁹, Arg⁴⁷⁴, Asn⁴⁹⁸, Arg⁵⁰³ and Lys⁵⁴⁵, as well as to the highly conserved residue Phe⁴⁴⁰ gave rise to enzymes

SUBMITTER: Rodriguez G 

PROVIDER: S-EPMC6616362 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature