Regulation of D-glucose-6-phosphate dehydrogenase from Schizosaccharomyces pombe.
D-Glucose-6-phosphate dehydrogenase is a regulatory enzyme of the oxidative pentose phosphate pathway in Schizasaccharomyces pombe. The enzyme is subject to negative cooperative regulation by D-glucose-6-phosphate as characterized by the Hill coefficient of 0.68 +/- 0.04. D-Glyceraldehyde-3-phosphate and D-ribulose-5-phosphate rectify the negative cooperativity as evidenced from a change in the Hill coefficients to 0.98 +/- 0.05 and 1.02 +/- 0.05, respectively. These pentose phosphate pathway intermediates also inhibit the enzyme competitively with respect to D-glucose-6-phosphate. Thus, D-glucose-6-phosphate dehydrogenase provides an avenue for regulating the partitioning of D-glucose between the redundant branches of the oxidative phosphate pathway in S. pombe.
Tsai
C S
CS
Department of Chemistry, Carleton University, Ottawa, ON, Canada. stsai@ccs.carleton.ca
Chen
Q
Q
D004305:Dose-Response Relationship, Drug; D015966:Gene Expression Regulation, Fungal; D005954:Glucosephosphate Dehydrogenase / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000302:isolation & purification; D007700:Kinetics; D012568:Schizosaccharomyces / Q000378:metabolism*
D005954:Glucosephosphate Dehydrogenase