[Objective] To achieve efficient expression of the alkaline laccase PIE5 in Coprinopsis cinerea with molasses as a substitute for glucose as the carbon source. [Methods] We enhanced the laccase production in C. cinerea by either exogenous addition of the invertase GspInv or endogenous co-expression of GspInv to hydrolyze sucrose in molasses. The fermentation conditions were optimized based on the laccase activity. [Results] With 40 g/L molasses as the carbon source, strain CcPIE5-14 achieved the laccase activity of (11.9±1.2) U/mL, while sucrose remained unutilized in the fermentation liquid. Upon addition of exogenous GspInv, sucrose in the fermentation liquid was hydrolyzed into fructose and glucose, and strain CcPIE5-14 exhibited the peak laccase activity of (14.8±0.7) U/mL in the medium with 30 g/L molasses. Co-expression of GspInv in CcPIE5-14 generated the engineered strain CcPIE5-14-GspInv-12, which demonstrated the maximum laccase activity of (28.1±2.4) U/mL in the mKjalke medium. When using molasses as the carbon source for laccase production, strain CcPIE5-14-GspInv-12 achieved the peak laccase activity of (20.1±2.7) U/mL, which represented a 2.24-fold increase over that of the parental strain CcPIE5-14. Following fermentation condition optimization, strain CcPIE5-14-GspInv-12 attained the maximum laccase activity of (44.6±2.6) U/mL, which marked a 2.22-fold enhancement over the pre-optimization level. [Conclusion] The engineered strain CcPIE5-14-GspInv-12, co-expressing laccase and invertase, demonstrates efficient production of the alkaline laccase PIE5 in C. cinerea with cost-effective molasses as the carbon source.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |