NAPRT1 dimer transfers PRIB to NCA to form NAMN

Cytosolic nicotinate phosphoribosyltransferase (NaPRT) catalyzes the Mg++-dependent reaction of nicotinate and phosphoribosyl pyrophosphate to form nicotinate mononucleotide (NaMN, nicotinate D-ribonucleotide) and pyrophosphate. The active form of the enzyme is a homodimer (Preiss and Handler 1958; Niedel and Dietrich 1973; Hara et al. 2007).

细胞质中的烟酸磷酸核糖转移酶（NaPRT）催化烟酸与磷酸核糖焦磷酸在镁离子（Mg++）依赖性反应下生成烟酸单核苷酸（NaMN，烟酸D-核糖核苷酸）和焦磷酸。该酶的活性形式为同源二聚体（Preiss and Handler 1958；Niedel and Dietrich 1973；Hara et al. 2007）。