title: Purification and characterization of methylmalonyl-CoA epimerase from Propionibacterium shermanii.
abstract: Methylmalonyl-CoA epimerase, which specifically interconverts the (2R)- and (2S)- epimers of methylmalonyl-CoA, was purified 95-fold from Propionibacterium shermanii by a new method that affords apparently homogeneous enzyme, in 80-100mg quantities, in yields representing about 40% of the activity in cell-free extracts. The specific activity of the purified enzyme, 10.1 mukat/mg, is much greater than previously reported. Native methylmalonyl-CoA epimerase has Mr about 33000, and apparently consists of two identical subunits. The purified enzyme is stable indefinitely when stored at -20 degrees C and pH 8.5, but contrary to previous reports it is not unusually acid-stable. The activity of methylmalonyl-CoA epimerase is increased by Co2+, and to a smaller extent by Ni2+, Mn2+ and Zn2+.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D002413:Cations, Divalent / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D007535:Isomerases / Q000302:isolation & purification; D008670:Metals / Q000032:analysis; D011424:Propionibacterium / Q000201:enzymology*; D019998:Racemases and Epimerases / Q000037:antagonists & inhibitors / Q000302:isolation & purification
chemical_list: D000596:Amino Acids; D002413:Cations, Divalent; D008670:Metals; D007535:Isomerases; D019998:Racemases and Epimerases; C021581:methylmalonyl-coenzyme A racemase