Folate-dependent enzyme, that displays both transferase and deaminase activity. Serves to channel one-carbon units from formiminoglutamate to the folate pool. Binds and promotes bundling of vimentin filaments originating from the Golgi. 5-formimidoyltetrahydrofolate + L-glutamate = (6S)-5,6,7,8-tetrahydrofolate + N-formimidoyl-L-glutamate 5-formimidoyltetrahydrofolate + 2 H(+) = 5,10-methenyltetrahydrofolate + NH4(+) Amino-acid degradation; L-histidine degradation into L-glutamate; L-glutamate from N-formimidoyl-L-glutamate (transferase route): step 1/1. Homooctamer, including four polyglutamate binding sites. The subunits are arranged as a tetramer of dimers, and form a planar ring-shaped structure. More abundantly located around the mother centriole. The disease is caused by variants affecting the gene represented in this entry. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. In the C-terminal section; belongs to the cyclodeaminase/cyclohydrolase family. In the N-terminal section; belongs to the formiminotransferase family.