Inhibitor studies of methionyl-tRNA transformylase of Euglena gracilis.
Inhibitor studies of the only known eukaryotic methionyl-tRNA transformylase (10-formyltetrahydrofolate:L-methionyl-tRNA N-transformylase, EC 2.1.2.9) were carried out. All the natural pteroylglutamic acid derivatives examined, with the exception of pteroylglutamic acid, are inhibitors. The most effective is 5-methyltetrahydrofolate (5-CH3-H4PteGlu) (KI = 3 . 10(-6) M), which is the only noncompetitive inhibitor of the enzyme. All the other derivatives tested are competitive, and H4PteGlu shows a cooperative inhibition. These and other data obtained with pteroylglutamic analogues show that, in contrast to the bacterial enzyme, Euglena transformylase is also inhibited by compounds without a fully reduced pyrazine ring and is very sensitive to compounds with a methyl group in position 5 or 10 of the pteridine ring.
D000217:Acyltransferases / Q000037:antagonists & inhibitors*; D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D005056:Euglena gracilis / Q000201:enzymology*; D005492:Folic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D019877:Hydroxymethyl and Formyl Transferases; D007700:Kinetics; D009239:N-Formylmethionine / Q000037:antagonists & inhibitors; D012346:RNA, Transfer, Amino Acyl / Q000037:antagonists & inhibitors; D013763:Tetrahydrofolates / Q000494:pharmacology
D012346:RNA, Transfer, Amino Acyl; D013763:Tetrahydrofolates; D009239:N-Formylmethionine; D005492:Folic Acid; D019877:Hydroxymethyl and Formyl Transferases; C021561:methionyl-tRNA formyltransferase; D000217:Acyltransferases; C005984:5-methyltetrahydrofolate