title: Effect of strain differences on heat-susceptibility of L-asparaginase in the guinea pig.
abstract: Effect of urea on the activity of serum L-asparaginase in outbred guinea pigs (Hartley) was examined for comparison between heat-resistant and heat-sensitive types. The heat-resistant serum L-asparaginase was much more stable to urea-treatment than the heat-sensitive serum enzyme, and the urea-inactivation of the serum enzyme was protected by Na+ or K+. Liver L-asparaginase of the guinea pig, in which the serum enzyme was resistant to heat, was also resistant to heat, and vice versa, although liver enzyme was much more sensitive to heat than serum enzyme. The heat inactivation of liver enzyme was also protected by Na+. Similar results were also demonstrated on purified serum L-asparaginase, although the amino acid compositions between the two purified enzyme preparations were slightly different. When the animal having heat-resistant serum L-asparaginase were crossed with each other, serum enzyme of the resultant progenies was also resistant to heat, and vice versa. The serum enzyme of two inbred strains (JY-1, Hartley/F) was thermostable and the enzyme of the other (Strain 2, Strain 13) was thermolabile.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001215:Asparaginase / Q000235:genetics* / Q000378:metabolism; D005260:Female; D006168:Guinea Pigs / Q000235:genetics*; D006358:Hot Temperature; D008099:Liver / Q000201:enzymology; D008297:Male; D012964:Sodium / Q000494:pharmacology; D013045:Species Specificity; D014508:Urea / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D014508:Urea; D012964:Sodium; D001215:Asparaginase