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. 1978 Jan 1;169(1):225–228. doi: 10.1042/bj1690225

A reappraisal of the reaction pathway of pyruvate carboxylase.

S B Easterbrook-Smith, J C Wallace, D B Keech
PMCID: PMC1184212  PMID: 629748

Abstract

The reaction pathway catalysed by pyruvate carboxylase was re-examined by using two independent experimental approaches not previously applied to this enzyme. To avoid the variable stoicheiometry associated with oxaloacetate formation, the reaction rate was measured by following release of Pi. Initial velocities, when plotted as a function of varying concentrations of either MgATP2- or HCO3-, at fixed concentrations of pyruvate, gave in double-reciprocal-form families of straight intersecting lines. Further, when the reaction velocity was determined as a function of varying MgATP2- concentrations by using pyruvate, 3-fluoropyruvate and 2-oxobutyrate as alternative carboxyl-acceptor substrates, the slopes of the double-reciprocal plots were significantly different. Both results support a sequential reaction pathway.

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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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