The Role of Active-Site Residues Phe98, His239, and Arg243 in DNA Binding and in the Catalysis of Human Uracil-DNA Glycosylase SMUG1.

ABSTRACT: Human SMUG1 (hSMUG1) hydrolyzes the N-glycosidic bond of uracil and some uracil lesions formed in the course of epigenetic regulation. Despite the functional importance of hSMUG1 in the DNA repair pathway, the damage recognition mechanism has been elusive to date. In the present study, our objective was to build a model structure of the enzyme-DNA complex of wild-type hSMUG1 and several hSMUG1 mutants containing substitution F98W, H239A, or R243A. Enzymatic activity of these mutant enzymes was examined by polyacrylamide gel electrophoresis analysis of the reaction product formation and pre-steady-state analysis of DNA conformational changes during enzyme-DNA complex formation. It was shown that substitutions F98W and H239A disrupt specific contacts generated by the respective wild-t

SUBMITTER: Iakovlev DA 

PROVIDER: S-EPMC6749576 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature