A High-Resolution Crystal Structure of a Psychrohalophilic α-Carbonic Anhydrase from Photobacterium profundum Reveals a Unique Dimer Interface.

ABSTRACT: Bacterial α-carbonic anhydrases (α-CA) are zinc containing metalloenzymes that catalyze the rapid interconversion of CO2 to bicarbonate and a proton. We report the first crystal structure of a pyschrohalophilic α-CA from a deep-sea bacterium, Photobacterium profundum. Size exclusion chromatography of the purified P. profundum α-CA (PprCA) reveals that the protein is a heterogeneous mix of monomers and dimers. Furthermore, an "in-gel" carbonic anhydrase activity assay, also known as protonography, revealed two distinct bands corresponding to monomeric and dimeric forms of PprCA that are catalytically active. The crystal structure of PprCA was determined in its native form and reveals a highly conserved "knot-topology" that is characteristic of α-CA's. Similar to other bacterial α-CA's, PprC

SUBMITTER: Somalinga V 

PROVIDER: S-EPMC5148590 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature