The Role of the Hydrogen Bond Network in Maintaining Heme Pocket Stability and Protein Function Specificity of <i>C. diphtheriae</i> Coproheme Decarboxylase.

ABSTRACT: Monoderm bacteria accumulate heme b via the coproporphyrin-dependent biosynthesis pathway. In the final step, in the presence of two molecules of H₂O₂, the propionate groups of coproheme at positions 2 and 4 are decarboxylated to form vinyl groups by coproheme decarboxylase (ChdC), in a stepwise process. Decarboxylation of propionate 2 produces an intermediate that rotates by 90° inside the protein pocket, bringing propionate 4 near the catalytic tyrosine, to allow the second decarboxylation step. The active site of ChdCs is stabilized by an extensive H-bond network involving water molecules, specific amino acid residues, and the propionate groups of the porphyrin. To evaluate the role of these H-bonds in the pocket stability and enzyme functionality, we charac

SUBMITTER: Sebastiani F 

PROVIDER: S-EPMC9953210 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature