Tags: Protein.
Protein disulfide-isomerase is an enzyme that in humans is encoded by the P4HB gene.This gene encodes the beta subunit of prolyl 4-hydroxylase a highly abundant multifunctional enzyme that belongs to the protein disulfide isomerase family. When present as a tetramer consisting of two alpha and two beta subunits this enzyme is involved in hydroxylation of prolyl residues in preprocollagen.