Properties and mechanism of d -glucosaminate-6-phosphate ammonia-lyase: An aminotransferase family enzyme with d -amino acid specificity
作者:Robert S. Phillips、Samuel C. Ting、Ange G. Tetsadjio、Kaitlin L. Anderson、Kyle M. Friez、Katherine A. Miller、Timothy R. Hoover
DOI:10.1016/j.bbapap.2017.12.006
日期:2018.7
reaction catalyzed by the DgaF protein to give d-glyceraldehyde-3-phosphate and pyruvate. We have now developed an improved synthesis of G6P which gives a higher yield. The DGL reaction is of mechanistic interest because it is one of only a few enzymes in the pyridoxal-5'-phosphate (PLP) dependent aminotransferase superfamily known to catalyze reaction of a d-amino acid substrate. The pH dependence of
肠炎沙门氏菌鼠伤寒沙门氏菌利用多种生长底物,其中一些相对较新。这些异常底物之一是d-氨基葡萄糖,它由dga操纵子中编码的酶代谢。d-葡萄糖基葡萄糖酸盐通过磷酸转移酶系统(由DgaABCD组成)转运并转化为d-葡萄糖苷6-磷酸酯(G6P)。dgaE的蛋白质产物d-氨基葡萄糖6-磷酸氨基分解酶(DGL)将G6P转换为2-keto-3-deoxygluconate-6-磷酸盐,该蛋白质在DgaF蛋白质的催化下进行逆醛醇缩合反应,得到d-甘油醛- 3-磷酸和丙酮酸。我们现在已经开发了改进的G6P合成方法,可以提高产率。DGL反应具有机械意义,因为它是吡ido醛5'中仅有的几种酶之一 磷酸酯(PLP)依赖性氨基转移酶超家族,可催化d-氨基酸底物的反应。DGL的pH依赖性显示在7.5-8.5的最佳值,这表明需要催化碱。α-甘油磷酸酯和无机磷酸酯是弱竞争性抑制剂,Ki值接近30mM,d-丝氨酸既