[Allosteric properties of phosphorylase b].
Rabbit skeletal muscle phosphorylase b was separated into two fractions by column chromatography on AMP-Sepharose. The first fraction protein was eluted by glucose-6-phosphate while the second fraction protein was eluted in an AMP concentration gradient. The bulk of the protein eluate was represented by the first fraction protein. Chromatography of phosphorylase b from bovine skeletal muscle under identical conditions also resulted in two fractions, however, with a reverse correlation: the bulk protein of this fraction was eluted by AMP. It was shown that the two phosphorylase b forms eluted by glucose-6-phosphate and AMP differ by their kinetic and physico-chemical properties as well as by the SH-group reactivity. The phosphorylase b forms eluted by the nucleotide were practically uninhibited by glucose-6-phosphate. It can thus be assumed that the equilibrium between the "active" (R) and "inactive" (T) conformations of the protein changes depending on metabolic peculiarities of a given tissue used as a source for enzyme isolation.
D000249:Adenosine Monophosphate / Q000378:metabolism; D000494:Allosteric Regulation; D000818:Animals; D002417:Cattle; D002850:Chromatography, Gel; D007700:Kinetics; D009132:Muscles / Q000201:enzymology*; D010763:Phosphorylase b / Q000037:antagonists & inhibitors / Q000302:isolation & purification*; D006005:Phosphorylases / Q000302:isolation & purification*; D011817:Rabbits
D000249:Adenosine Monophosphate; D010763:Phosphorylase b; D006005:Phosphorylases
Allostericheskie svoĭstva fosforilazy b.