Effect of nitrous oxide-induced inactivation of vitamin B12 on glycinamide ribonucleotide transformylase and 5-amino-4-imidazole carboxamide transformylase.
Exposure to nitrous oxide (N2O) in vivo is accompanied by oxidation of cob[I]-alamin to the inactive cob[III]alamin [1]. There is loss of methionine synthetase activity [2] and evidence of depressed supply of single carbon units at the formate level of oxidation [3,4,5]. We measured the effect of inactivation of B12 on the folate-dependent transformylases concerned in purine synthesis. After 24 h exposure to N2O there was a significant fall in glycinamide ribonucleotide transformylase (EC 2.1.2.2) and a significant increase in 5-amino-4-imidazole carboxamide transformylase (EC 2.1.2.3).
D000217:Acyltransferases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D000818:Animals; D019877:Hydroxymethyl and Formyl Transferases; D008099:Liver / Q000201:enzymology*; D008297:Male; D009609:Nitrous Oxide / Q000494:pharmacology*; D051027:Phosphoribosylaminoimidazolecarboxamide Formyltransferase; D051026:Phosphoribosylglycinamide Formyltransferase; D051381:Rats; D011919:Rats, Inbred Strains; D014805:Vitamin B 12 / Q000037:antagonists & inhibitors / Q000378:metabolism*
D019877:Hydroxymethyl and Formyl Transferases; D051026:Phosphoribosylglycinamide Formyltransferase; D051027:Phosphoribosylaminoimidazolecarboxamide Formyltransferase; D000217:Acyltransferases; D009609:Nitrous Oxide; D014805:Vitamin B 12