Liu Yuan-Ning, Hong Li-Li, Liu Ming, Guo Qing-Chun, Kong Jian-Qiang
Institute of Materia Medica, Chinese Academy of Medical Sciences & Peking Union Medical College (State Key Laboratory of Bioactive Substance and Function of Natural Medicines & NHC Key Laboratory of Biosynthesis of Natural Products), Beijing 100050, P. R. China.
Hebei Lansheng Biotech Co., Ltd., Mayu Village, Jinzhou City, Shijiazhuang, Hebei 052263, P. R. China.
ACS Synth Biol. 2021 Dec 17;10(12):3583-3594. doi: 10.1021/acssynbio.1c00532. Epub 2021 Nov 30.
The diversity expansion of testosterone17--β-glycosides (TGs) will increase the probability of screening more active molecules from their acetylated derivatives with anticancer activities. Glycosyltransferases (GTs) responsible for the increased diversity of TGs, however, were seldom documented. Herein, a glycosyltransferase OsSGT2 with testosterone glycodiversification capacity was identified from through transcriptome-wide mining. Specifically, OsSGT2 was demonstrated to be reactive with testosterone and eight donors. OsSGT2 displayed both sugar-aglycon and sugar-sugar GT activities. OsSGT2-catalyzed testosterone glycodiversification could be achieved, generating testosterone monoglycosides and disglycosides with varied percentage conversions. Among the eight donors, the conversion of UDP-Glc was the highest, approaching 90%, while the percentage conversions of UDP-GlcNAc, UDP-Gal, helicin, and UDP-Rha were less than 10%. Protein engineering toward F395 was thus performed to improve the conversion of UDP-GlcNAc. Eight variants displayed increased conversions and the mutant F395C got the highest conversion of 72.11 ± 7.82%, eight times more than that of the wild-type. This study provides a promising alternative for diversity expansion of TGs, also significant insights into the molecular basis for the conversion improvement of sugar donors.
睾酮17-β-糖苷（TGs）的多样性扩展将增加从其具有抗癌活性的乙酰化衍生物中筛选出更多活性分子的可能性。然而，负责TGs多样性增加的糖基转移酶（GTs）鲜有文献报道。在此，通过全转录组挖掘从[具体来源未给出]中鉴定出一种具有睾酮糖基多样化能力的糖基转移酶OsSGT2。具体而言，已证明OsSGT2可与睾酮及八种供体发生反应。OsSGT2表现出糖-苷元和糖-糖GT活性。可以实现OsSGT2催化的睾酮糖基多样化，生成具有不同转化率的睾酮单糖苷和二糖苷。在八种供体中，UDP-Glc的转化率最高，接近90%，而UDP-GlcNAc、UDP-Gal、helicin和UDP-Rha的转化率低于10%。因此对F395进行了蛋白质工程改造以提高UDP-GlcNAc的转化率。八个变体表现出更高的转化率，突变体F395C的转化率最高，为72.11±7.82%，是野生型的八倍。本研究为TGs的多样性扩展提供了一个有前景的选择，也为糖供体转化改善的分子基础提供了重要见解。
