生物技术通报 ›› 2024, Vol. 40 ›› Issue (10): 305-314.doi: 10.13560/j.cnki.biotech.bull.1985.2024-0384

• 研究报告 • 上一篇    下一篇

基于计算设计的GH11家族木聚糖酶CDBFV的热稳定性改造及潜在机制研究

韩雪1,2(), 张阿娜3, 王海燕4, 辛凤姣1,2, 谷天一1,2(), 王钰璐1,2()   

  1. 1.中国农业科学院农产品加工研究所,北京 100193
    2.中国农业科学院农产品加工与营养健康研究院(沧州),沧州 061001
    3.山西农业大学食品学院,晋中 030600
    4.北京挑战生物技术有限公司,北京 100081
  • 收稿日期:2024-04-15 出版日期:2024-10-26 发布日期:2024-11-20
  • 通讯作者: 王钰璐,女,博士,助理研究员,研究方向 :生物大分子结构与功能 ;E-mail: wnewyx@163.com
    谷天一,男,助理研究员,研究方向 :食品酶学与合成生物学 ;E-mail: 18501151081@163.com
  • 作者简介:韩雪,女,博士研究生,研究方向:食品酶学;E-mail: njhanxue1995@163.com
    第一联系人:

    张阿娜为本文共同第一作者

  • 基金资助:
    企业合作项目(饲用酶产品开发与升级),中央级公益性科研院所基本科研业务费专项(S2022JBKY-13);中国农业科学院农产品加工研究所创新工程院所重点任务(CAAS-ASTIP-G2022-IFST-07)

Computer-aided Thermostability Engineering and Underlying Mechanism Investigation of the GH11 Family Xylanase CDBFV

HAN Xue1,2(), ZHANG A-na3, WANG Hai-yan4, XIN Feng-jiao1,2, GU Tian-yi1,2(), WANG Yu-lu1,2()   

  1. 1. Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing 100193
    2. Institute of Food Science Technology Nutrition and Health(Cangzhou), Chinese Academy of Agricultural Sciences, Cangzhou 061001
    3. College of Food Science, Shanxi Agricultural University, Jinzhong 030600
    4. Beijing Challenge Biotechnology Co., Ltd., Beijing 100081
  • Received:2024-04-15 Published:2024-10-26 Online:2024-11-20

摘要:

【目的】瘤胃真菌Neocallimastix patriciarum GH11家族木聚糖酶CDBFV在饲料、食品等领域具有良好应用前景,提高其热稳定性对其生产应用十分重要。【方法】使用分子动力学模拟、机器学习等策略设计潜在CDBFV热稳定性突变体,在大肠杆菌和毕赤酵母中进行异源表达纯化,测定最适反应条件、比酶活和85℃孵育3 min后相对剩余活力,通过结构分析明确热稳定性提高机制。【结果】位于CDBFV N端基序36GNNS39具有较高柔性,对其改造设计的单突变体N37P和N38V在85℃孵育3 min后,相对活力分别降低至70.3%和55.1%,较野生型(48.7%)提升了21.6%和6.5%;进而,在相对活力提升显著的N37P基础上叠加已报道优势突变体N88G,构建双突变体N37P/N88G,其相对活力达到了73.4%,较野生型提高了24.7%;此外,将N37P/N88G在毕赤酵母中进行了分泌表达,在85℃处理3 min后,相对活力达到了88.8%;结构分析表明,N37P突变的引入使得CDBFV形成了新的氢键相互作用,降低活性位点附近柔性,并干预了糖基化形成,进而提高了热稳定性。【结论】成功得到了高耐热双突变体N37P/N88G,为提高GH11家族木聚糖酶的热稳定性改造提供了新的思路和方法,有望推动CDBFV在饲料工业等高温环境下的广泛应用。

关键词: 木聚糖酶, 柔性区域, 热稳定性, 毕赤酵母, 理性设计

Abstract:

【Objective】 The rumen fungus Neocallimastix patriciarum GH11 family xylanase CDBFV has good application prospects in feed, food and related industries. Improving its thermal stability is crucial for optimizing its production and utilization. 【Method】 Potential thermostable mutants of CDBFV were designed using strategies such as molecular dynamics simulation and machine learning. And then heterologous expression and purification were carried out in Escherichia coli and Pichia pastoris. The optimal reaction conditions, specific enzyme activity and the relative residual activity after incubation at 85℃ for 3 min were determined, and the mechanisms for improving thermal stability were clarified through structural analysis. 【Result】 The 36GNNS39 motif at the N-terminus of CDBFV was highly flexible. Single mutant N37P and N38V created by modifying this motif showed the relative activites of 70.3% and 55.1% after incubation at 85℃ for 3 min, representing increases of 21.6% and 6.5% respectively compared to the wild-type(48.7%). Based on the significant increase in relative activity observed in N37P, combined with the previously reported beneficial mutant N88G, the double mutant N37P/N88G was constructed. This double mutant presented a relative activity of 73.4%, and 24.7% improvement over the wild-type. In addition, when N37P/N88G was expressed in Pichia pastoris, it had a relative activity of 88.8% after treatment at 85℃ for 3 min. Structural analysis indicated that the N37P mutation introduced new hydrogen bonds in CDBFV, decreased the flexibility of the active site and disrupted glycosylation, thereby improving its thermal stability. 【Conclusion】 This study successfully generated the high-temperature-resistance double mutant N37P/N88G, offering new insights and approaches for improving the thermal stability of GH11 family xylanases. This advancement is anticipated to facilitate the extensive utilization of CDBFV in high-temperature settings like the feed industry.

Key words: xylanase, flexible region, thermostability, Pichia pastoris, rational design