FEATURES

FAMILY

DESCRIPTION

Also known as PUR8_ECOLI, purB. Catalyzes two reactions in de novo purine nucleotide biosynthesis. Catalyzes the breakdown of 5-aminoimidazole- (N-succinylocarboxamide) ribotide (SAICAR or 2-[5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamido]succinate) to 5-aminoimidazole-4-carboxamide ribotide (AICAR or 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide) and fumarate, and of adenylosuccinate (ADS or N(6)-(1, 2-dicarboxyethyl)-AMP) to adenosine monophosphate (AMP) and fumarate., (Microbial infection) Catalyzes the conversion of 2-amino-2'-deoxyadenylo-succinate to dZMP and fumarate, when the bacterium is infected by a phage that produces the substrate of this reaction, a step in the synthesis of dZTP (2-amino-2'-deoxyadenosine 5'-triphosphate), which is a nucleotide then used by the phage as a DNA polymerase substrate. Homotetramer. Residues from neighboring subunits contribute catalytic and substrate-binding residues to each active site.

EXTERNAL LINKS

purB

Adenylosuccinate lyase

purB

Molecular Synopsis