Purification and characterization of lactate dehydrogenase from Varanus liver.
- Author:
Masood H JAVED MH
1
;
Syed MI AZIMUDDIN
;
Abida N HUSSAIN
;
Asifa AHMED
;
Mohammad ISHAQ
Author Information
1. AGA KHAN UNIV, DEPT BIOCHEM, KARACHI 74800, PAKISTAN.
- Publication Type:Original Article
- Keywords:
LDH isoenzyme;
liver;
properties;
purification;
Varanus bengalensis
- MeSH:
Chromatography;
Electrophoresis, Agar Gel;
Electrophoresis, Polyacrylamide Gel;
Hydrogen-Ion Concentration;
Ions;
Isoenzymes;
L-Lactate Dehydrogenase*;
Lactic Acid*;
Liver*;
NAD;
Pyruvic Acid
- From:Experimental & Molecular Medicine
1997;29(1):25-30
- CountryRepublic of Korea
- Language:English
-
Abstract:
Lactate dehydrogenase was purified 21-fold from liver of Varanus bengalensis using colchicine-sepharose column chromatography. The crude enzyme showed two isoenzymes (LDH-5 and LDH-4) by agarose gel electrophoresis (AGE). The purified enzyme showed a single band after SDS-PAGE corresponding to molecular mass of 35 kDa. The molecular mass of native enzyme was about 140 kDa. The optimum pH for the forward reaction was 7.5 while that for the reverse reaction was pH 9.5. The K-m values for pyruvate, NADH, lactate and NAD(+) were 0.17 +/- 0.037, 0.02 +/- 0.004, 12.4 +/- 3.05 and 0.38 +/- 0.032 mM, respectively. Pre-heating of enzyme showed that its t(50) was 40-50 degrees C. Oxalate and n-hexanediol were inhibitors for both forward and reverse reactions. Among divalent ions, Cu++ was shown to be more effective inhibitor for the forward reaction.
