Rocchigiani M, Micheli V, Duley J A, Simmonds H A
Dipartimento di Biologia Molecolare, Università di Siena, Italia.
Anal Biochem. 1992 Sep;205(2):334-6. doi: 10.1016/0003-2697(92)90444-c.
A radiochemical reverse-phase-high-performance liquid chromatography-linked method to measure the activity of nicotinamide phosphoribosyltransferase (EC 2.4.2.12) in crude lysates of human red blood cells is described. The apparent Km for nicotinamide was in the micromolar range, much lower than that described in human erythrocytes in the past. The enzyme activity in crude hemolysates was found to be extremely low (21 +/- 3.5 nmol x h-1 x g-1 Hb); nevertheless, the low Km for nicotinamide might account for the production of pyridine nucleotides reported by us for intact erythrocytes incubated at low, physiological concentrations of this substrate.
描述了一种放射性化学反相高效液相色谱联用方法，用于测量人红细胞粗裂解物中烟酰胺磷酸核糖基转移酶（EC 2.4.2.12）的活性。烟酰胺的表观Km在微摩尔范围内，远低于过去在人红细胞中所描述的值。发现粗溶血产物中的酶活性极低（21±3.5 nmol·h⁻¹·g⁻¹血红蛋白）；然而，烟酰胺的低Km可能解释了我们报道的在该底物的低生理浓度下孵育的完整红细胞中吡啶核苷酸的产生。
