Characterization of UMP synthase in dairy cattle heterozygous for a lethal recessive trait |
| |
Authors: | Kathryn K. Harden James L. Robinson |
| |
Affiliation: | (1) Department of Animal Sciences, Division of Nutritional Sciences, University of Illinois, 315 Animal Sciences Laboratory, 61801 Urbana, Illinois |
| |
Abstract: | UMP synthase was characterized biochemically in dairy cattle heterozygous for a deficiency of this enzyme. Both activities comprising this bifunctional enzyme are decreased, with OMP decarboxylase more affected than orotate phosphoribosyltransferase. Immunotitration of UMP synthase activity revealed the presence of the protein product of the mutant allele in the heterozygous animals. UMP synthases from normal and deficient cattle were not distinguished from one another by kinetic constants, responses to inhibitors, pH profiles, or thermal lability. It was concluded that the 50% reduction in enzyme activity in heterozygous cattle is the result of the presence of only half the normal level of catalytically active UMP synthase. |
| |
Keywords: | UMP synthase enzyme deficiency genetic defect heterozygote dairy cattle |
本文献已被 SpringerLink 等数据库收录! |
|