title: Properties of muscle phosphorylase b from a hagfish, Paramyxine atami.
abstract: Phosphorylase b was purified to homogeneity from the muscle of a hagfish (Paramyxine atami), as judged by electrophoretic and immunological criteria. The purified enzyme was partially but not fully activated by AMP, and its conversion into the a form resulted in a three-fold increase in activity. The enzyme was stimulated by SO4(2-), and kinetic experiments showed that SO4(2-) markedly increased the affinity of enzyme toward substrates: in the presence and absence of 0.35 M SO4(2-), the apparent Km values of hagfish phosphorylase b were 0.04 and 1.3% for glycogen, 8.7 and 66 mM for glucose 1-phosphate, and 0.05 and 1.0 mM for AMP, respectively. Electrophoretic and immunological data indicated that the hagfish possessed a single molecular form of phosphorylase, like the lamprey. Some immunological relatedness between the hagfish enzyme and the enzyme from lamprey or skate was demonstrated.
mesh_terms: D000818:Animals; D000906:Antibodies; D000936:Antigen-Antibody Complex; D006196:Hagfishes; D005779:Immunodiffusion; D007700:Kinetics; D009132:Muscles / Q000201:enzymology*; D009928:Organ Specificity; D010763:Phosphorylase b / Q000302:isolation & purification / Q000378:metabolism*; D006005:Phosphorylases / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D000906:Antibodies; D000936:Antigen-Antibody Complex; D010763:Phosphorylase b; D006005:Phosphorylases