Data for: Oriented efficient biosynthesis of rare ginsenoside Rh2 from PPD by compiling UGT-Yjic mutant with sucrose synthase

Ginsenoside Rh2 (3β-O-Glc-protopanaxadiol), a trace but an important pharmacological component of ginseng, has exhibited excellent medicinal potential. Many studies have found that the synthesis of Rh2 by UDP-glucosyltransferase (UGT) is an alternative production strategy. In this study, Yjic from B. subtilis 168 was found to synthesize ginsenoside F12 (3β,12β-Di-O-Glc-protopanaxadiol) and Rh2 at a ratio of 7:3. Yjic regioselectivity toward Rh2 synthesis was successfully improved using a semi-rational design including structure-guided alanine scanning and saturation mutations. As a result, mutant M315F was found to efficiently synthesize Rh2 (~99%) and block the further glycosylation of C12-OH. The circulation of UDPG was achieved by combining M315F with AtSuSy through a cascade reaction. Furthermore, an extraordinarily high yield of Rh2 (3.7 g/L) was attained in an aqueous solvent system with 17% DMSO (v/v) through the fed-batch feeding of PPD. This study presents the high potential for the oriented preparation of ginsenoside Rh2.人参皂苷Rh2（Ginsenoside Rh2，3β-O-葡萄糖基原人参二醇）作为人参中的微量但关键的药效成分，展现出优异的药用潜力。多项研究证实，利用尿苷二磷酸葡萄糖基转移酶（UDP-glucosyltransferase，UGT）合成Rh2是一种可行的替代生产策略。本研究发现，来自枯草芽孢杆菌168的Yjic可同时合成人参皂苷F12（3β,12β-二-O-葡萄糖基原人参二醇）与Rh2，二者产出比例为7:3。通过结构引导丙氨酸扫描与饱和突变等半理性设计策略，本研究成功优化了Yjic催化合成Rh2的区域选择性。结果表明，突变体M315F可高效合成Rh2（产物纯度约99%），并阻断C12-羟基的后续糖基化反应。通过将M315F与拟南芥蔗糖合酶（AtSuSy）构建级联反应体系，实现了尿苷二磷酸葡萄糖（UDPG）的循环再生。此外，通过原人参二醇（PPD）的补料分批补加，在含17%（v/v）二甲基亚砜（DMSO）的水相溶剂体系中，获得了极高产量的Rh2（达3.7 g/L）。本研究证实了定向制备人参皂苷Rh2的巨大应用潜力。