| 摘 要： | This paper reports the isolation and some properties of L-amino acid oxidase from Ophi-ophagus hannah venom. The differences between L-amino acid oxidase from Ophiophagusohannah and that from other sources in specific activity, properties and the spectrum of iso-zymes are noticeable. The result of electrophoresis on polyacrylamide gel shows that this purified enzyme ishomogenous. The molecular weight determined by gradient polyacrylamide gel slab (4--30%)is around 15×10~4 dalton. The molecular weight of the subunit determined by SDS gradient gelelectrephoresis (4--30%) is around 7.3×10~4 dalton. Therefore, this enzyme is composed of twosubunits. The absorption spectrum reveals that there are two FADs in each molecule. The optimum pH of enzymic reaction is around 8.7--9.0 when L-leucine is used as substrate.The inhibition of the preducts is noticeable when substrate concentration goes beyond 3mM.This enzyme is heat stable and its activity would not decrease obviously after heating at 55℃for 40 min. A linear relationship between enzyme concentration and reaction rate was noticedwhen enzyme concentration was below 5.7μg/ml.
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