5-aminoimidazole ribotide (AIR) is a branch point metabolite in the biosynthetic pathways of purines and thiamin. Although AIR cannot be efficiently taken up by most bacteria, 5-aminoimidazole riboside (AIRs) can. Aminoimidazole riboside kinase catalyses the phosphorylation of AIRs into AIR to feed into purine and thiamin biosynthesis pathways.
Defined by 4 residues: GLY:A-269 [auth A-249]ALA:A-270 [auth A-250]GLY:A-271 [auth A-251]ASP:A-272 [auth A-252]