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. 1968 Feb;106(3):581–586. doi: 10.1042/bj1060581

Aspartate aminotransferase. The effects of ionic concentration on kinetic constants of both isoenzymes

T R C Boyde 1
PMCID: PMC1198545  PMID: 5639913

Abstract

1. The Michaelis constants for both isoenzymes for both substrates depend strongly on ionic concentration, being approximately proportional to phosphate concentration over considerable ranges. This is probably an effect of anions only. 2. In the absence of added salt, Km (2-oxoglutarate) (anionic isoenzyme) is so small as to be indeterminate. 3. Km (l-aspartate) (anionic isoenzyme) passes through a sharp minimum at about 3·3mm-phosphate. It is not clear whether this is a specific effect of phosphate. 4. Both substrates are inhibitory at sufficiently low ionic concentrations. 5. A modified graphical procedure is described for the derivation of the kinetic constants.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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