Yeast Pyruvate Kinase

Yeast Pyruvate Kinase

The kinetic properties of purified yeast pyruvate kinase were investigated. The enzyme showed cooperative kinetics toward the essential activating monovalent cations K+ and NH4+, Mg2+, and phosphoenolpyruvate. Fructose 1,6diphosphate, which yielded homotropic cooperative kinetics and did not affect maximal velocity, transformed the sigmoidal kinetics of Kf and NH4+, Mgz+, and phosphoenolpyruvat...

The regulatory properties of yeast pyruvate kinase.

The kinetics of pyruvate kinase from Saccharomyces cerevisiae were studied in assays at pH 6.2 where the relationships between the initial velocities of the catalysed reaction and the concentrations of the substrates ADP, phosphoenolpyruvate and Mg2+ are non-hyperbolic. The findings were represented empirically by the exponential model for a regulatory enzyme. The analysis shows that ADP, phosp...

A revised preparation of yeast (Saccharomyces cerevisiae) pyruvate kinase.

A revised preparation of pyruvate kinase from saccharomyces cerevisiae is reported. By purifying this cold-labile enzyme at room temperature, an improved recovery and specific activity was obtained. More than 350 mg of pure enzyme with a specific activity of 350 to 400 units/mg at 30 degrees were obtained from a pound of fresh yeast. The last step of the preparation, passage of the enzyme over ...

Prevalence of Pyruvate Kinase Deficiency among the Newborns (Shiraz-Iran)

Background: The frequency of pyruvate kinase (PK) deficiency, an autosomal recessive defect, is approximately 3 per 10,000 individuals in Shiraz and surrounding areas, and is increased due to high consanguinity marriage frequency. The purpose of this study is to obtain data on the frequency and spectrum of gene mutation of PK in newborns, from Shiraz and surrounding areas. Materials and Methods...

Yeast pyruvate kinase. I. Purification and some chemical properties.