Substrate specificity of manganese-activated prolidase in control and prolidase-deficient cultured skin fibroblasts.

Abstract

Skin fibroblasts have a single enzyme, Mn2+-activated prolidase, that hydrolyses a range of amino acid-proline dipeptides. Two cases of prolidase deficiency showed a marked loss of activity against glycyl-proline irrespective of Mn2+ conditions. However, the abnormal enzyme showed only moderate reductions in activity against phenylalanyl-, alanyl-, and leucyl-proline following preincubation with Mn2+ or addition of Mn2+ with the substrate. Control prolidase was stable to prolonged preincubation with Mn2+, whereas the abnormal prolidase was progressively inactivated. The findings indicate, for at least the present two cases, that prolidase deficiency results from an altered rather than a marked reduction in the amount of normal enzyme.

• Authors: J Butterworth, D Priestman
• Journal: Journal of inherited metabolic disease (J Inherit Metab Dis) Vol. 7 Issue 1 Pg. 32-4 ( 1984) ISSN: 0141-8955 [Print] United States
• PMID: 6429439 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Manganese
• Proline
• Dipeptidases
• proline dipeptidase

Topics

• Amino Acid Metabolism, Inborn Errors (enzymology)
• Chromatography, Gel
• Chromatography, Ion Exchange
• Dipeptidases (deficiency)
• Fibroblasts (enzymology)
• Humans
• Male
• Manganese (metabolism)
• Proline (metabolism)
• Skin (enzymology)
• Substrate Specificity