Pasin Thiago M, Lucas Rosymar C, de Oliveira Tássio B, McLeish Michael J, Polizeli Maria de Lourdes T M
Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP 14049-900 Brazil.
Department of Chemistry and Chemical Biology, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202 USA.
3 Biotech. 2024 Jul;14(7):178. doi: 10.1007/s13205-024-04021-7. Epub 2024 Jun 6.
Daily agro-industrial waste, primarily cellulose, lignin, and hemicellulose, poses a significant environmental challenge. Harnessing lignocellulolytic enzymes, particularly endo-1,4-β-xylanases, for efficient saccharification is a cost-effective strategy, transforming biomass into high-value products. This study focuses on the cloning, expression, site-directed mutagenesis, purification, three-dimensional modeling, and characterization of the recombinant endo-1,4-β-xylanase (XlnA) from in . This work includes evaluation of the stability at varied NaCl concentrations, determining kinetic constants, and presenting the heterologous expression of XlnAΔ36 using pET22b(+). The expression led to purified enzymes with robust stability across diverse pH levels, exceptional thermostability at 50 °C, and 96-100% relative stability after 24 h in 3.0 M NaCl. Three-dimensional modeling reveals a GH11 architecture with catalytic residues Glu 132 and 22. XlnAΔ36 demonstrates outstanding kinetic parameters compared to other endo-1,4-β-xylanases, indicating its potential for industrial enzymatic cocktails, enhancing saccharification. Moreover, its ability to yield high-value compounds, such as sugars, suggests a promising and ecologically positive alternative for the food and biotechnology industries.
日常农业工业废弃物，主要是纤维素、木质素和半纤维素，对环境构成了重大挑战。利用木质纤维素酶，特别是内切-1,4-β-木聚糖酶进行高效糖化是一种具有成本效益的策略，可将生物质转化为高价值产品。本研究重点关注来自[具体来源未给出]的重组内切-1,4-β-木聚糖酶（XlnA）的克隆、表达、定点诱变、纯化、三维建模和表征。这项工作包括评估在不同NaCl浓度下的稳定性、确定动力学常数，以及展示使用pET22b(+)载体的XlnAΔ36的异源表达。该表达产生的纯化酶在不同pH水平下具有强大的稳定性，在50°C时具有出色的热稳定性，并且在3.0 M NaCl中24小时后相对稳定性为96 - 100%。三维建模揭示了具有催化残基Glu 132和22的GH11结构。与其他内切-1,4-β-木聚糖酶相比，XlnAΔ36表现出出色的动力学参数，表明其在工业酶混合物中的潜力，可增强糖化作用。此外，它产生高价值化合物（如糖）的能力，为食品和生物技术行业提供了一种有前景且对生态有益的替代方案。
