Artículo de revista
Purification and Characterization of Avian Liver Mevalonate-5-pyrophosphate Decarboxylase
Fecha
1982Registro en:
Biochemistry, Volumen 21, Issue 19, 2018, Pages 4646-4650
15204995
00062960
10.1021/bi00262a020
Autor
Alvear, Marysol
Jabalquinto, Ana María
Eyzaguirre, Jaime
Cardemil, Emilio
Institución
Resumen
Mevalonate-5-pyrophosphate decarboxylase [ATP:5-diphosphomevalonate car boxy-lyase (dehydrating), EC 4.1.1.33] has been purified 5800 times from chicken liver and obtained in a stable and highly purified form. The protein is a dimer of molecular weight 85400 ± 1941, and its subunits were not resolved by gel electrophoresis in denaturing conditions. The purified enzyme does not require the presence of SH-containing reagents for either activity or stability. The enzyme shows a high specificity for adenosine 5'-triphosphate (ATP) and requires for activity a divalent metal cation, Mg2+ being most effective. The optimum pH for the enzyme ranges from 4.0 to 6.5. Inhibitory effects for the enzyme activity were detected by citrate, phthalate, and phosphate. The isoelectric point, as determined by column chromatofocusing, is 4.8. The kinetics are hyperbolic for both substrates, showing a sequential mechanism; true Km values of 0.0141 mM and 0.504 mM have been obtained for mevalonate-5-pyrophosp