提高溶细胞多糖单加氧酶的酶活性和稳定性。
Improving the Enzymatic Activity and Stability of a Lytic Polysaccharide Monooxygenase.
机构信息
Qingdao New Energy Shandong Laboratory, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China.
Shandong Energy Institute, Qingdao 266101, China.
出版信息
Int J Mol Sci. 2023 May 18;24(10):8963. doi: 10.3390/ijms24108963.
Lytic Polysaccharide Monooxygenases (LPMOs) are copper-dependent enzymes that play a pivotal role in the enzymatic conversion of the most recalcitrant polysaccharides, such as cellulose and chitin. Hence, protein engineering is highly required to enhance their catalytic efficiencies. To this effect, we optimized the protein sequence encoding for an LPMO from (LPMO10A) using the sequence consensus method. Enzyme activity was determined using the chromogenic substrate 2,6-Dimethoxyphenol (2,6-DMP). Compared with the wild type (WT), the variants exhibit up to a 93.7% increase in activity against 2,6-DMP. We also showed that LPMO10A can hydrolyze -nitrophenyl-β-D-cellobioside (PNPC), carboxymethylcellulose (CMC), and phosphoric acid-swollen cellulose (PASC). In addition to this, we investigated the degradation potential of LPMO10A against various substrates such as PASC, filter paper (FP), and Avicel, in synergy with the commercial cellulase, and it showed up to 2.7-, 2.0- and 1.9-fold increases in production with the substrates PASC, FP, and Avicel, respectively, compared to cellulase alone. Moreover, we examined the thermostability of LPMO10A. The mutants exhibited enhanced thermostability with an apparent melting temperature increase of up to 7.5 °C compared to the WT. The engineered LPMO10A with higher activity and thermal stability provides a better tool for cellulose depolymerization.
溶细胞聚糖单加氧酶(LPMOs)是一类铜依赖性酶,在最顽固的多糖(如纤维素和几丁质)的酶促转化中发挥着关键作用。因此,需要进行蛋白质工程来提高它们的催化效率。为此,我们使用序列共识方法对 (LPMO10A)的蛋白质序列进行了优化。使用显色底物 2,6-二甲氧基苯酚(2,6-DMP)来测定酶活性。与野生型(WT)相比,变体的 2,6-DMP 活性最高提高了 93.7%。我们还表明,LPMO10A 可以水解 -硝基苯-β-D-纤维二糖苷(PNPC)、羧甲基纤维素(CMC)和磷酸膨胀纤维素(PASC)。除此之外,我们还研究了 LPMO10A 与商业纤维素酶协同作用对各种底物(如 PASC、滤纸(FP)和 Avicel)的降解潜力,与单独使用纤维素酶相比,它在 PASC、FP 和 Avicel 等底物上的产量分别提高了 2.7 倍、2.0 倍和 1.9 倍。此外,我们还研究了 LPMO10A 的热稳定性。与 WT 相比,突变体的表观熔点提高了 7.5°C,表现出更高的热稳定性。与野生型相比,具有更高活性和热稳定性的工程化 LPMO10A 为纤维素的解聚提供了更好的工具。