InterPro domain: IPR044524

This protein family consists of HisA and its homologues from archaea, bacteria, fungi and plants. HisA is a phosphoribosylformimino-5-aminoimidazole carboxamide ribotide isomerase (also known as 1-(5-phosphoribosyl)-5-(5-phosphoribosylamino methylideneamino) imidazole-4-carboxamide isomerase 5.3.1.16 ) that catalyses the fourth step in histidine biosynthes [ 1 ]. It is closely related to the enzyme HisF for the sixth step. Examples of this enzyme in Actinobacteria have been found to be bifunctional, also possessing phosphoribosylanthranilate isomerase activity [ 2 ]. This entry also includes chloroplastic HisA homologue from Arabidopsis [ 3 ] and His6 from budding yeasts [ 4 ].

1. Clinical and immunologic responses of pigs to African swine fever virus isolated from the Western Hemisphere. Am J Vet Res 45, 711-4
2. Occurrence of a putative ancient-like isomerase involved in histidine and tryptophan biosynthesis. EMBO Rep. 4, 296-300
3. Molecular cloning and characterization of the gene encoding N'-[(5'-phosphoribosyl)-formimino]-5-aminoimidazole-4-carboxamide ribonucleotide (BBM II) isomerase from Arabidopsis thaliana. Mol. Gen. Genet. 259, 216-23
4. Paralogous histidine biosynthetic genes: evolutionary analysis of the Saccharomyces cerevisiae HIS6 and HIS7 genes. Gene 197, 9-17