Portal de Periódicos da CAPES

Extracellular expression of mutant CotA-laccase SF in Escherichia coli and its degradation of malachite green

2020; Elsevier BV; Volume: 193; Linguagem: Inglês

10.1016/j.ecoenv.2020.110335

1090-2414

Kai-Zhong Xu, Hui Ma, Yajing Wang, Yujie Cai, Xiangru Liao, Zheng-Bing Guan,

melanin and skin pigmentation

In this study, mutant CotA-laccase SF was successfully expressed in Escherichia coli by co-expression with phospholipase C. The optimized extracellular expression of CotA-laccase SF was 1257.22 U/L. Extracellularly expressed CotA-laccase SF exhibits enzymatic properties similar to intracellular CotA-laccase SF. CotA-laccase SF could decolorize malachite green (MG) under neutral and alkaline conditions. The Km and kcat values of CotA-laccase SF to MG were 39.6 mM and 18.36 s-1. LC-MS analysis of degradation products showed that MG was finally transformed into 4-aminobenzophenone and 4-aminophenol by CotA-laccase. The toxicity experiment of garlic root tip cell showed that the toxicity of MG metabolites decreased. In summary, CotA-laccase SF had a good application prospect for degrading malachite green.