Northeast Forestry University, Harbin 150040, China.
Northeast Forestry University, Harbin 150040, China.
Int J Biol Macromol. 2023 Jun 15;240:124189. doi: 10.1016/j.ijbiomac.2023.124189. Epub 2023 Mar 27.
White rot fungi can degrade lignin and play a significant role in the recycling of carbon resources for environmental protection. Trametes gibbosa is the main white rot fungus in Northeast China. The main acids produced by T. gibbosa degradation, include long-chain fatty acids, lactic acid, succinic acid, and some small molecular compounds for example benzaldehyde. A variety of proteins respond to lignin stress and play an important role in xenobiotics metabolism, metal ion transport, and redox. Coordinated regulation and detoxification activation of HO produced in oxidative stress by peroxidase coenzyme system and Fenton reaction. The Dioxygenase cleavage pathway and β-ketoadipic acid pathway are the main oxidation pathways of lignin degradation, which mediate the entry of "COA" into the TCA cycle. In the joint action of hydrolase and coenzyme, cellulose, hemicellulose, and other polysaccharides are degraded and finally converted to glucose to participate in energy metabolism. The expression of the laccase (Lcc_1) protein was verified by E. coli. Also, the Lcc_1 overexpression mutant was established. The morphology of mycelium was dense and the lignin degradation rate was improved. We completed the first non-directional mutation of in T. gibbosa. It also improved the mechanism of T. gibbosa in response to lignin stress.
白腐真菌可以降解木质素,在环境保护中对碳资源的循环利用起着重要作用。栓菌是中国东北地区主要的白腐真菌。T. gibbosa 降解产生的主要酸包括长链脂肪酸、乳酸、琥珀酸和一些小分子化合物,如苯甲醛。多种蛋白质对木质素胁迫作出响应,在异生物质代谢、金属离子运输和氧化还原中发挥重要作用。过氧化物酶辅酶系统和 Fenton 反应协调调节 HO 在氧化应激中产生的活性氧的解毒激活。双加氧酶裂解途径和β-酮己二酸途径是木质素降解的主要氧化途径,介导“COA”进入 TCA 循环。在水解酶和辅酶的共同作用下,纤维素、半纤维素和其他多糖被降解,最终转化为葡萄糖参与能量代谢。通过大肠杆菌验证了漆酶(Lcc_1)蛋白的表达,还建立了 Lcc_1 过表达突变体。菌丝体形态致密,木质素降解率提高。我们完成了 T. gibbosa 中的第一个非定向突变。这也提高了 T. gibbosa 对木质素胁迫的响应机制。