Characterization of galactose-1-phosphate uridyl-transferase and galactokinase in human organs from the fetus and adult.

Some properties of galactose-1-phosphate uridyltransferase (EC 2.7.7.

Prenatal diagnosis of Lesch-Nyhan syndrome and some characteristics of hypoxanthine-guanine phosphoribosyltransferase and adenine phosphoribosyltransferase in human tissues and cultivated cells.

Activities of phosphoribosyltransferase for hypoxanthine and adenine were investigated in erythrocytes and human tissues of fetuses and adults as well as in cultivated fibroblasts and amniotic fluid cells. Kinetic characteristics of these enzymes were also studied in patients with the Lesch-Nyhan syndrome and with partial deficiency for hypoxanthine phosphoribosyltransferase (HGPRTase), and their obligate heterozygotes. The affinity of HGPRTase for both substrates in partial deficiency decreased to 13 to 20% of normal and by a less degree in its heterozygotes (50 to 65% of normal).

Lysosomal enzyme activities of human fetal organs during development.

The developmental patterns of four lysosomal enzymes have been investigated in liver, kidney, lung, heart, spleen, muscle and brain tissues of human fetuses at varius gestational ages. The largest increment in the activity of all four enzymes, namely acid alpha-glucosidase, alpha-galactosidase, beta-galactosidase and acid phosphatase had been observed in kidney with a 6- to 12-fold increase between the second and third trimester of gestation. The activity of all liver and spleen enzymes also increased considerably during these periods.

Characteristics of galactokinase and galactose-1-phosphate uridyltransferase in cultivated fibroblasts and amniotic fluid cells.

The kinetic characteristics of galactose-1-phosphate uridyltransferase and galactokinase in cultivated fibroblasts and amniotic fluid cells were investigated. The Km values of galactokinase for galactose at 2.0 mM ATP are 0.