Abstract: Co-culture is an effective way to improve laccases fermentation level. The previous study showed that the transcription levels of lacc2 and lacc6 changed significantly during co-culture. In this study, lacc2 and lacc6 were successfully cloned and expressed in Pichia pastoris GS115. The crude enzyme solution of LACC2 and LACC6 were purified to investigate the enzymatic properties. When ABTS was used as the substrate, the optimal temperatures and pH of LACC2 and LACC6 were 50°C and 3.0, respectively. Moreover, low concentrations of K+, Cu2+, Co2+ and Mn2+ enhanced the activities of LACC2 more than LACC6. In addition, LACC2 showed better tolerance to organic reagents and surfactants than LACC6, while LACC2 was more vulnerable to the inhibitors than LACC6. The enzyme kinetics results showed that ABTS was the optimal substrate of LACC2 and LACC6, and the Km of LACC2 and LACC6 were 0.13 mmol/L and 0.24 mmol/L, respectively. This study provided important basic data on the properties of isoenzymes for the mechanism analysis of R. mucilaginosa enhanced P. eryngii var. ferulae laccases production during co-culture, which was beneficial to the comprehensive analysis of the promotion mechanism.
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