Pyruvate carboxylase activity in chorionic villi: possibility of application to prenatal diagnosis.
Pyruvate carboxylase (PC) activity was assayed in 27 chorionic villi samples (CVS) obtained at 9-12 weeks of gestation. The kinetic properties of the CVS enzyme were similar to those of liver PC; more than 75% of PC activity was recovered in the mitochondrial fraction of CVS. Apparent Km for pyruvate, ATP, acetyl CoA and HCO3- in the presence of saturation concentrations of the other reactants, were 0.3, 0.44, 0.015 and 6.0 mmol/l, respectively. The optimum pH was 7.5-8.0. The activity of PC in CVS was 3.2 +/- 0.3 nmol/min/mg protein, which is severalfold higher than that of amniotic fluid fibroblasts.
Barash
V
V
Department of Clinical Biochemistry, Hadassah University Hospital, Jerusalem, Israel.
Khassis
S
S
Granat
M
M
Gutman
A
A
D002458:Cell Fractionation; D002824:Chorionic Villi / Q000201:enzymology*; D002950:Citrate (si)-Synthase / Q000378:metabolism; D005260:Female; D006801:Humans; D007700:Kinetics; D010920:Placenta / Q000201:enzymology; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011263:Pregnancy Trimester, Third; D011296:Prenatal Diagnosis; D011766:Pyruvate Carboxylase / Q000378:metabolism*; D012016:Reference Values
D002950:Citrate (si)-Synthase; D011766:Pyruvate Carboxylase