生物技术通报 ›› 2026, Vol. 42 ›› Issue (11): 164-173.doi: 10.13560/j.cnki.biotech.bull.1985.2025-1297
• 研究报告 • 上一篇
刘保财1,2, 胡学博3, 赵云青1,2, 黄颖桢1,2, 张武君1,2, 陈菁瑛1,2(
)
收稿日期:2025-11-28
出版日期:2026-11-26
发布日期:2026-11-03
通讯作者:
陈菁瑛cjy6601@163.com基金资助:
LIU Bao-cai1,2, HU Xue-bo3, ZHAO Yun-qing1,2, HUANG Ying-zhen1,2, ZHANG Wu-jun1,2, CHEN Jing-ying1,2(
)
Received:2025-11-28
Published:2026-11-26
Online:2026-11-03
摘要:
目的 发掘石仙桃中天麻素生物合成最后关键步骤的糖基转移酶基因,为利用工程菌高效生产天麻素奠定基础。 方法 采用双酶切法,克隆候选基因transcript28360/f2p0/1592(1592)和transcript17418/f3p0/2174(2174),以AsUGT为阳性对照,在大肠杆菌和酵母中进行表达。 结果 基因2174由1 413个核苷酸组成,编码470个氨基酸,大小约为51.12 kD,主要位于叶绿体中。基因1592由1 395个核苷酸组成,编码464个氨基酸,大小约为50.85 kD,主要位于细胞质中。3个酶催化天麻苷元的活性中心均有亮氨酸、苯丙氨酸、苏氨酸、谷氨酸等残基,可能是催化天麻苷元形成天麻素的关键活性残基。在大肠杆菌和酵母中表达表明,基因2174具有较高的催化天麻苷元生成天麻素的活性,是对照基因AsUGT的2.31-3.39倍,而基因1592具有较弱的催化活性。 结论 石仙桃中糖基转移酶基因2174和1592催化天麻苷元生成天麻素过程中存在活性差异,基因2174可作为工程菌生产天麻素关键酶的候选基因。
刘保财, 胡学博, 赵云青, 黄颖桢, 张武君, 陈菁瑛. 石仙桃中天麻素合成相关糖基转移酶基因的克隆与表达分析[J]. 生物技术通报, 2026, 42(11): 164-173.
LIU Bao-cai, HU Xue-bo, ZHAO Yun-qing, HUANG Ying-zhen, ZHANG Wu-jun, CHEN Jing-ying. Cloning and Expression Analysis of Glycosyltransferase Genes Involved in Gastrodin Biosynthesis in Pholidota chinensis Lindl.[J]. Biotechnology Bulletin, 2026, 42(11): 164-173.
| 引物名称 Primer name | 序列 Sequence(5′-3′) | 用途 Purpose |
|---|---|---|
| 2174-SpeI-F | GGACTAGTATGGAAATCGCTGGAT | Gene clone |
| 2174-BglII-R | GAAGATCTCTAAAGTGCTACGCTCTT | |
| 1592-SpeI-F | GGACTAGTATGGCTGATGGCAACCCA | |
| 1592-BglII-R | GAAGATCTTCACTTAGTAGCCGTTGAATCCTT | |
| 2174-F | GTTTAACTTTAAGAAGGAGATATACATATGCACCATCATCATCATCATATGGAAATCGCCG | Seamless gene clone |
| 2174-R | GGTGGTGGTGCTCGAGTGCGGCCGCAAGCTTTTACAGTGCCACACTTTTCCACTTAT | |
| 1592-F | GTTTAACTTTAAGAAGGAGATATACATATGCACCATCATCATCATCATATGGCTGATGGTAATCC | |
| 1592-R | GGTGGTGGTGCTCGAGTGCGGCCGCAAGCTTTTATTTGGTTGCGGTGCTATCTTTCAGA | |
| AsUGT-F | GTTTAACTTTAAGAAGGAGATATACATATGCACCATCATCATCATCATATGGAACATACCCCG | |
| AsUGT-R | GGTGGTGGTGCTCGAGTGCGGCCGCAAGCTTTTAGGTACTACTAATCTTATTTTCCCA |
表1 基因克隆PCR引物序列
Table 1 Primer sequences of PCR for gene clone
| 引物名称 Primer name | 序列 Sequence(5′-3′) | 用途 Purpose |
|---|---|---|
| 2174-SpeI-F | GGACTAGTATGGAAATCGCTGGAT | Gene clone |
| 2174-BglII-R | GAAGATCTCTAAAGTGCTACGCTCTT | |
| 1592-SpeI-F | GGACTAGTATGGCTGATGGCAACCCA | |
| 1592-BglII-R | GAAGATCTTCACTTAGTAGCCGTTGAATCCTT | |
| 2174-F | GTTTAACTTTAAGAAGGAGATATACATATGCACCATCATCATCATCATATGGAAATCGCCG | Seamless gene clone |
| 2174-R | GGTGGTGGTGCTCGAGTGCGGCCGCAAGCTTTTACAGTGCCACACTTTTCCACTTAT | |
| 1592-F | GTTTAACTTTAAGAAGGAGATATACATATGCACCATCATCATCATCATATGGCTGATGGTAATCC | |
| 1592-R | GGTGGTGGTGCTCGAGTGCGGCCGCAAGCTTTTATTTGGTTGCGGTGCTATCTTTCAGA | |
| AsUGT-F | GTTTAACTTTAAGAAGGAGATATACATATGCACCATCATCATCATCATATGGAACATACCCCG | |
| AsUGT-R | GGTGGTGGTGCTCGAGTGCGGCCGCAAGCTTTTAGGTACTACTAATCTTATTTTCCCA |
图1 石仙桃中RNA和克隆基因的凝胶电泳A:RNA凝胶电泳;B:克隆基因的凝胶电泳。M:DL2 000TM DNA marker;A1:基因1592;A2:基因AsUGT;A3:基因2174
Fig. 1 Gel electrophoresis of RNA and cloned genes in P. chinensisA: Gel electrophoresis of RNA. B: Gel electrophoresis of cloned genes. M: DL2 000TM DNA marker; A1:gene 1592; A2: gene AsUGT; A3: gene 2174
图2 pESC370与目的基因的双酶切及菌液验证A:1592和2174双酶切(A1:线性化pESC370;A2:未线性化pESC370;A3:未酶切1592;A4:已酶切1592;A5:已酶切2174;A6:未酶切2174)。B:pESC370-1592-Ura大肠杆菌菌液验证(B1-B8:pESC370-1592-Ura单克隆)。C:pESC370-AsUGT-Ura和pESC370-2174-Ura大肠杆菌菌液验证(C1-C6:pESC370-AsUGT-Ura单克隆;C7-C12:pESC370-2174-Ura单克隆)。M:DL2 000TM DNA marker
Fig. 2 Dual enzyme digestion of pESC370 with target gene and bacterial culture validationA: Double enzyme digestion of 1592 and 2174 (A1: linearized pESC370; A2: unlinearized pESC370; A3: unenzymatically digested 1592; A4: enzymatically digested 1592; A5: enzymatically digested 2174; A6: unenzymatically digested 2174). B: The pESC370-1592-Ura validation in E. coli bacterial fluid (B1-B8: The pESC370-1592-Ura monoclonal). C: pESC370-AsUGT-Ura and pESC370-2174-Ura validation in E. coli bacterial suspension (C1-C6: pESC370-AsUGT-Ura monoclonal; C7-C12: pESC370-2174-Ura monoclonal). M: DL2 000TM DNA marker
| 基因Gene | 氨基酸数Amino acid quantity (aa) | 相对分子质量Relative molecular weight (kD) | 等电点 PI | 不稳定指数Instability index | 脂肪族氨基酸指数Aliphatic index | 亲水性平均系数GRAVY | α螺旋 Alpha-helix (%) | 延长链Extended strand (%) | β转角 Beta-turn (%) | 无规则卷曲Random coil (%) | 亚细胞定位Subcellular localization |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2174 | 470 | 51.12 | 5.42 | 48.4 | 99.85 | 0.094 | 42.13 | 14.47 | 6.17 | 37.23 | chlo: 6, mito: 2, extr: 2, E.R.: 2, nucl: 1 |
| AsUGT | 470 | 51.80 | 5.87 | 44.84 | 94.64 | -0.042 | 43.83 | 14.04 | 7.23 | 34.89 | cyto: 7, chlo: 4, plas: 2 |
| 1592 | 464 | 50.85 | 5.43 | 42.25 | 95.56 | 0.028 | 42.03 | 14.44 | 6.68 | 36.85 | cyto: 8, chlo: 3, nucl: 2 |
表2 三个基因的理化特性
Table 2 Physicochemical properties of three genes
| 基因Gene | 氨基酸数Amino acid quantity (aa) | 相对分子质量Relative molecular weight (kD) | 等电点 PI | 不稳定指数Instability index | 脂肪族氨基酸指数Aliphatic index | 亲水性平均系数GRAVY | α螺旋 Alpha-helix (%) | 延长链Extended strand (%) | β转角 Beta-turn (%) | 无规则卷曲Random coil (%) | 亚细胞定位Subcellular localization |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2174 | 470 | 51.12 | 5.42 | 48.4 | 99.85 | 0.094 | 42.13 | 14.47 | 6.17 | 37.23 | chlo: 6, mito: 2, extr: 2, E.R.: 2, nucl: 1 |
| AsUGT | 470 | 51.80 | 5.87 | 44.84 | 94.64 | -0.042 | 43.83 | 14.04 | 7.23 | 34.89 | cyto: 7, chlo: 4, plas: 2 |
| 1592 | 464 | 50.85 | 5.43 | 42.25 | 95.56 | 0.028 | 42.03 | 14.44 | 6.68 | 36.85 | cyto: 8, chlo: 3, nucl: 2 |
图6 预测的3个基因的空间结构和与天麻苷元对接的活性中心A和D:2174;B和E:1592;C和F:AsUGT
Fig. 6 Predicted spatial structure of the three genes and active centers docked to gastrodigeninA and D: Gene 2174; B and E: gene 1592; C and F: gene AsUGT
图7 三个基因诱导表达产物的SDS-PAGE分析A:AsUGT;B:1592;C:2174。M:SDS-PAGE Protein marker;0:对照;1:15 ℃诱导16 h;2:37 ℃诱导16 h;3:15 ℃诱导上清;4:15 ℃诱导沉淀;5:37 ℃诱导上清;6:37 ℃诱导沉淀
Fig. 7 SDS-PAGE analysis of three genes induced expression productsA: AsUGT; B: 1592; C: 2174. M: SDS-PAGE Protein marker; 0: control; 1: induced at 15 ℃ for 16 h; 2: induced at 37 ℃ for 16 h; 3: induced at 15 ℃ for supernatants; 4: induced at 15 ℃ for precipitations; 5: induced at 37 ℃ for supernatants; 6: induced at 37 ℃ for precipitations
图8 三个基因的表达蛋白分离后SDS-PAGE分析A: AsUGT; B: 1592; C: 2174。M: SDS-PAGE Protein marker; 1:包涵体溶解后离心上清;2:上清同Ni-IDA孵育流出液; 3-5: 50 mmol/L咪唑的洗脱组分;6-8: 100 mmol/L咪唑的洗脱组分;9-13: 500 mmol/L咪唑的洗脱组分
Fig. 8 SDS-PAGE analysis of three genes isolated target proteinsA: AsUGT; B: 1592; C: 2174. M: SDS-PAGE Protein marker; 1: centrifugation supernatant after inclusion body lysis; 2: supernatant with Ni-IDA incubation effluent; 3-5: elution fractions of 50 mmol/L imidazole; 6-8: elution fractions of 100 mmol/L imidazole; 9-13: elution fractions of 500 mmol/L imidazole
图9 三个重组目标蛋白纯化后SDS-PAGE分析M: SDS-PAGE marker; 1:BSA 1.0 μg; 2:BSA 2.0 μg; 3:蛋白2174 1.0 μg; 4:蛋白2174 2.0 μg; 5:蛋白2174 3.0 μg; 6:蛋白1592 1.0 μg; 7:蛋白1592 2.0 μg; 8:蛋白1592 3.0 μg; 9:蛋白AsUGT 1.0 μg; 10:蛋白AsUGT 2.0 μg; 11:蛋白AsUGT 3.0 μg
Fig. 9 SDS-PAGE analysis of three purified recombinant target proteinsM: SDS-PAGE marker; 1: BSA 1.0 μg; 2: BSA 2.0 μg; 3: 2174 protein 1.0 μg; 4: 2174 protein 2.0 μg; 5: 2174 protein 3.0 μg; 6: 1592 protein 1.0 μg; 7: 1592 protein 2.0 μg; 8: 1592 protein 3.0 μg; 9: AsUGT protein 1.0 μg; 10: AsUGT protein 2.0 μg; 11: AsUGT protein 3.0 μg
图12 酵母菌液加入底物后催化活性差异A:底物;B:产物,红色的虚线是0-48 h之间,基因2174和AsUGT催化天麻苷元生成天麻素的回归直线,方程是以0-40 h和0-48 h所产生天麻素含量分别做的回归方程
Fig. 12 Differences in catalytic activity after adding substrates to yeast solutionsA: Substrate; B: product. The red dashed line indicates the regression line of gastrodin generation from gastrodigenin catalyzed by gene 2174 and AsUGT in 0-48 h. The equations were regression equations based on the gastrodin content produced from 0 to 40 h and 0 to 48 h, respectively
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