Main content area

High-level expression and biochemical characterization of a novel cold-active lipase from Rhizomucor endophyticus

Duan, Xiaojie, Zheng, Mingming, Liu, Yu, Jiang, Zhengqiang, Yang, Shaoqing
Biotechnology letters 2016 v.38 no.12 pp. 2127-2135
petroleum, Rhizomucor, cyclohexanes, fermentation, substrate specificity, Komagataella pastoris, fermenters, triacylglycerols, iso-octanes, carboxylic ester hydrolases, surfactants, genes, pH, solvents, hexane, heterologous gene expression, industrial applications, fungi
OBJECTIVES: To identify novel cold-active lipases from fungal sources and improve their production by heterologous expression in Pichia pastoris. RESULTS: A novel cold-active lipase gene (ReLipB) from Rhizomucor endophyticus was cloned. ReLipB was expressed at a high level in Pichia pastoris using high cell-density fermentation in a 5-l fermentor with the highest lipase activity of 1395 U/ml. The recombinant lipase (RelipB) was purified and biochemically characterized. ReLipB was most active at pH 7.5 and 25 °C. It was stable from pH 4.5–9.0. It exhibited broad substrate specificity towards p-nitrophenyl (pNP) esters (C₂–C₁₆) and triacylglycerols (C₂–C₁₂), showing the highest specific activities towards pNP laurate (231 U/mg) and tricaprylin (1840 U/mg), respectively. In addition, the enzyme displayed excellent stability with high concentrations of organic solvents including cyclohexane, n-hexane, n-heptane, isooctane and petroleum ester and surfactants. CONCLUSIONS: A novel cold-active lipase from Rhizomucor endophyticus was identified, expressed at a high level and biochemically characterized. The high yield and unique enzymatic properties make this lipase of some potential for industrial applications.