6eer

Publication Abstract from PubMed

The LodA-like proteins are a recently identified family of enzymes that rely on a cysteine tryptophylquinone (CTQ)1 cofactor for catalysis. They differ from other tryptophylquinone enzymes in that they are oxidases rather than dehydrogenases. GoxA is a member of this family that catalyzes the oxidative deamination of glycine. Our previous work with GoxA from Pseudoalteromonas luteoviolaceae demonstrated that this protein forms a stable intermediate upon anaerobic incubation with glycine. The spectroscopic properties of this species were unique among those identified for tryptophylquinone enzymes characterized to date. Here we use X-ray crystallography and resonance Raman spectroscopy to identify the GoxA catalytic intermediate as a product Schiff-base. Structural work additionally highlights features of the active site pocket that confer substrate specificity, intermediate stabilization and catalytic activity. The unusual properties of GoxA are discussed within the context of the other tryptophylquinone enzymes.

Structural and spectroscopic characterization of a product Schiff-base intermediate in the reaction of the quinoprotein glycine oxidase, GoxA.,Avalos D, Sabuncu S, Mamounis KJ, Davidson VL, Moenne-Loccoz P, Yukl ET Biochemistry. 2019 Jan 3. doi: 10.1021/acs.biochem.8b01145. PMID:30605596^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.