College of Life Sciences, Henan Agricultural University, Zhengzhou, China.
Prep Biochem Biotechnol. 2022;52(6):611-617. doi: 10.1080/10826068.2021.1977949. Epub 2021 Sep 22.
We previously reported an enzymatic pathway for conversion of nonfood cellulose to starch (,110 (18): 7182-7187, 2013), in which the two sequential enzymes cellobiose phosphorylase (CBP) from and potato alpha-glucan phosphorylase (PGP) from were the two key enzymes responsible for the whole conversion rate. In this work CBP and PGP were fused to form a large enzyme and it turned out that the fusion protein could exhibit a good bifunctionality when PGP moiety was put at the N-terminus and CBP moiety at the C-terminus (designated as PGP-CBP). Although the coupled reaction rate of PGP-CBP was decreased by 23.0% compared with the free enzymes, substrate channeling between the two active sites in PGP-CBP was formed, demonstrated by the introduction of the competing enzyme of PGP to the reaction system. The potential of PGP-CBP fusion enzyme being applied to the conversion of cellulose to amylose was discussed.
我们之前报道了一种将非食用纤维素转化为淀粉的酶促途径（,110（18）：7182-7187, 2013），其中两个连续的酶——来自 的纤维二糖磷酸化酶（CBP）和来自 的马铃薯α-葡聚糖磷酸化酶（PGP）——是负责整个转化率的两个关键酶。在这项工作中，CBP 和 PGP 被融合形成一个大酶，结果表明当 PGP 部分位于 N 端而 CBP 部分位于 C 端时，融合蛋白可以表现出良好的双功能性（指定为 PGP-CBP）（,110（18）：7182-7187, 2013）。虽然与游离酶相比，PGP-CBP 的偶联反应速率降低了 23.0%，但在 PGP-CBP 中两个活性位点之间形成了底物通道，这是通过向反应系统中引入 PGP 的竞争酶来证明的。讨论了 PGP-CBP 融合酶在纤维素向直链淀粉转化中的应用潜力。
