Autor: |
Linlin Wang, Zhihui Jiang, Jiahe Zhang, Kuan Chen, Meng Zhang, Zilong Wang, Binju Wang, Min Ye, Xue Qiao |
Jazyk: |
angličtina |
Rok vydání: |
2023 |
Předmět: |
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Zdroj: |
Nature Communications, Vol 14, Iss 1, Pp 1-12 (2023) |
Druh dokumentu: |
article |
ISSN: |
2041-1723 |
DOI: |
10.1038/s41467-023-41599-7 |
Popis: |
Abstract Acetylation contributes to the bioactivity of numerous medicinally important natural products. However, little is known about the acetylation on sugar moieties. Here we report a saponin acetyltransferase from Astragalus membranaceus. AmAT7-3 is discovered through a stepwise gene mining approach and characterized as the xylose C3′/C4′-O-acetyltransferse of astragaloside IV (1). To elucidate its catalytic mechanism, complex crystal structures of AmAT7-3/1 and AmAT7-3A310G/1 are obtained, which reveal a large active pocket decided by a specific sequence AADAG. Combining with QM/MM computation, the regiospecificity of AmAT7-3 is determined by sugar positioning modulated by surrounding amino acids including #A310 and #L290. Furthermore, a small mutant library is built using semi-rational design, where variants A310G and A310W are found to catalyze specific C3′-O and C4′-O acetylation, respectively. AmAT7-3 and its variants are also employed to acetylate other bioactive saponins. This work expands the understanding of saponin acetyltransferases, and provide efficient catalytic tools for saponin acetylation. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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