The ammonium sulfate activation of phosphorylase b

[摘要]

The ammonium sulfate activation of phosphorylase b has been studied. Ammonium sulfate, when present in high concentrations, induces properties of phosphorylase a in phosphorylase b, such as an enhanced affinity for AMP, a reversal of the glucose-6-P inhibition and enzyme tetramerization. The data are consistent with the interpretation that sulfates bind to the Ser-14 site and the sulfate-protein interactions at this site are responsible for activation of phosphorylase b.

[学科分类] 生物化学/生物物理

[关键词] Phosphorylase b;Phosphorylase a;Activation;Electron spin resonance;Tetramerization;Structure-function;glucose-1-P;α-D-glucopyranose-1-phosphate;glucose-6-P;glucose-6-phosphate;4-(2-iodoacetamido)2;2;6;6-tetramethyl piperidinyloxyl;iodoacetamide spin label;ESR;electron spin resonance;glycogen phosphorylase;1;4-α-D-glucan;orthophosphate o-glucosyltransferase (EC 2.4.1.1)