磷酸吡哆醛补救途径两个关键酶的研究进展

Research advance in two key enzymes involved in the pyridoxal 5′-phosphate salvage pathway

维生素B_6(VB_6)包括6个可相互转换的吡啶衍生物。其中,磷酸吡哆醛(PLP)作为140多种细胞酶的辅酶,在生物体内发挥重要作用。动物从食物中获得VB_6,通过由吡哆醛激酶和磷酸吡哆醇氧化酶构成的补救途径合成PLP。PLP依赖酶的正常功能乃至人体最佳健康状态,依赖于细胞中PLP的平衡供给。然而,就PLP的动态平衡和调节机制以及PLP合成后的转移机制而言,目前还知之甚少,是一个富有挑战性的研究领域。为此,综述PLP补救途径两个关键酶的研究进展。

In six different vitamin B6 forms, pyridoxal 5＇-phosphate （PLP） is a catalytically active form of VB6 It acts as cofactor in more than 140 different enzyme reactions. Animals obtain PLP form VB6 from diet and recycled it in a ＂salvage pathway＂, which essentially involves two ubiquitous enzymes： pyridoxal kinase and pyridoxine5＇-phosphate oxidase. Proper functioning of PLP-dependent enzymes and thus the optimal health of the human body are dependent upon an adequate level of PLP in the cell. However, the mechanism and regulation of PLP homeostasis, and the mechanism of addition of PLP to the apo-B6-enzymes are poorly understood and represent a very challenging research field. This article summarizes the current knowledge on the two enzymes involved in the PLP salvage pathway.