Cloning, baculovirus expression, and characterization of the alpha subunit of prolyl 4-hydroxylase from the nematode Caenorhabditis elegans. This alpha subunit forms an active alpha beta dimer with the human protein disulfide isomerase/beta subunit.

摘要: Prolyl 4-hydroxylase (EC 1.14.11.2) catalyzes the formation of 4-hydroxyproline in collagens. The vertebrate enzyme is an alpha 2 beta tetramer, subunit which identical to protein disulfide-isomerase (PDI). We report here on cloning catalytically important from Caenorhabditis elegans. This polypeptide consists 542 amino acids and signal peptide 16 additional residues. C. elegans 25 longer than human subunit, mainly because a 32-amino-acid C-terminal extension present only former. overall acid sequence identity between these two subunits 45%, 127-amino region close C terminus being especially well conserved. When was expressed together with PDI/beta insect cells by baculovirus vectors, active prolyl formed, but surprisingly this elegans/human appeared be dimer. specific activity comparable that enzyme, most other catalytic properties were also highly similar. Nevertheless, not inhibited poly(L-proline). data indicate multifunctional can form having marked differences their sequences.