[Different character of zinc ion binding with lactate dehydrogenase M4 in diluted and concentrated solutions]
Biofizika
|March 1, 1996
Abstract:
The study of the melting characteristics of lactate dehydrogenase M4 and Zn/lactate dehydrogenase at pH 6.5-8.5 by microcalorimetric methods shows that in dilute solutions of the enzyme (0.05% lactate dehydrogenase solution) one Zn ion causes destabilisation of enzyme structure, attended by a decrease of melting temperature throughout the entire pH interval under study. Concentrated solutions of the enzyme (0.4% lactate dehydrogenase solution) are a seat of such conformational changes of the latter which affect the character of Zn ions binding depending on pH.
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