Kod eukariota, ovaj enzim je bifunkcionalan. On takođe deluje kao glutamat formimidoiltransferaza (EC 2.1.2.5).
Reference
^Rabinowitz, J.C. & Pricer, W.E. (1956). „Formiminotetrahydrofolic acid and methenyltetrahydrofolic acid as intermediates in the formation of N10-formyltetrahydrofolic acid”. J. Am. Chem. Soc. 78: 5702—5704.