Crystal Structure of a Highly Thermostable α-Carbonic Anhydrase from Persephonella marina EX-H1.

ABSTRACT: Bacterial α-type carbonic anhydrase (α-CA) is a zinc metalloenzyme that catalyzes the reversible and extremely rapid interconversion of carbon dioxide to bicarbonate. In this study, we report the first crystal structure of a hyperthermostable α-CA from Persephonella marina EXH1 (pm CA) in the absence and presence of competitive inhibitor, acetazolamide. The structure reveals a compactly folded pm CA homodimer in which each monomer consists of a 10-stranded β-sheet in the center. The catalytic zinc ion is coordinated by three highly conserved histidine residues with an exchangeable fourth ligand (a water molecule, a bicarbonate anion, or the sulfonamide group of acetazolamide). Together with an intramolecular disulfide bond, extensive interfacial networks of hydrogen bonds, ionic and

SUBMITTER: Kim S 

PROVIDER: S-EPMC6602146 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature