Crystal structure of a family VIII β-lactamase fold hydrolase reveals the molecular mechanism for its broad substrate scope.

ABSTRACT: Family VIII esterases present similarities to class C β-lactamases, which show nucleophilic serines located at the S-X-X-K motif instead of the G-X-S-X-G or G-D-S-(L) motif shown by other carboxylesterase families. Here, we report the crystal structure of a novel family VIII (subfamily VIII. I) esterase (EH₇ ; denaturing temperature, 52.6 ± 0.3 °C; pH optimum 7.0-9.0) to deepen its broad substrate range. Indeed, the analysis of the substrate specificity revealed its capacity to hydrolyse nitrocefin as a model chromogenic cephalosporin substrate (40.4 ± 11.4 units·g^-1 ), and a large battery of 66 structurally different esters (up to 1730 min^-1 ), including bis(2-hydroxyethyl)-terephthalate (241.7 ± 8.5 units·g^-1 ) and the mycotoxin T-2 (1220 ± 52 

SUBMITTER: Cea-Rama I 

PROVIDER: S-EPMC9795927 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature