Folate activity of human lymphocytes determined by measurement of serine synthesis.

摘要: A method has been developed for measuring the folate activity in isolated human lymphocytes by quantitating incorporation of 14C-formate into serine. Isotope experiments showed that serine was formed from glucose and mainly catabolized to CO2, NH3, two one-carbon fragments. 10% is incorporated protein 5% converted metabolic acids. Small amounts were metabolized Krebs cycle intermediates other amino acids also over ethanolamine choline glycine. Forcing adding 6.7 mmol/l 20 glycine incubation medium gave 24 an 9.2 ± 0.4% (S.E.M.) added formate per 109 4 h. The not influenced pyridoxal phosphate or tetrahydrofolic acid. effect serine, homocysteine, methionine on established model experiments, but does appear be significance clinical applicabi...