title: Construction of Aspergillus niger lipase mutants with oil-water interface independence.
abstract: Based on previous bioinformational analytical results [Shu ZY, et al. Biotechnol Prog 2009;25:409-16], four A. niger lipase (ANL) mutants, ANL-Ser84Gly, ANL-Asp99Pro, ANL-Lys108Glu and ANL-EαH (obtained by replacing the lid domain of ANL with the corresponding domain from A. niger feruloyl esterase), were constructed to screen out ANL mutants with oil-water interface independence. ANL-S84G displayed a pronounced interfacial activation, while ANL-D99P and ANL-K108E displayed no interfacial activation. The specific activity of ANL-S84G towards p-nitrophenyl esters decreased from 29.8% to 76.5% compared with that of ANL, while the specific activity of ANL-D99P towards p-nitrophenyl palmitate increased 2.2-fold. The thermostability of ANL-K108E was almost unchanged, while the thermostability of ANL-S84G and ANL-D99P significantly decreased compared with that of ANL. The construction of oil-water interface-independent ANL mutants would help to further understand the mechanism of lipase interfacial activation.
authors: Engineering Research Center of Industrial Microbiology, Ministry of Education, Fujian Normal University, Fuzhou, Fujian 350108, PR China. shuzhengyu@gmail.com
authors: Zhengyu
authors: Z
authors: Shu
authors: Jiguang
authors: J
authors: Wu
authors: Longyin
authors: L
authors: Xue
authors: Ruifeng
authors: R
authors: Lin
authors: Yongmei
authors: Y
authors: Jiang
authors: Lianghua
authors: L
authors: Tang
authors: Xin
authors: X
authors: Li
authors: Jianzhong
authors: J
authors: Huang
mesh_terms: D000595:Amino Acid Sequence; D001234:Aspergillus niger / Q000201:enzymology* / Q000235:genetics*; D004789:Enzyme Activation; D004795:Enzyme Stability; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D008049:Lipase / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009154:Mutation / Q000235:genetics*; D009821:Oils; D010843:Pichia / Q000235:genetics / Q000378:metabolism; D016133:Polymerase Chain Reaction; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D014867:Water
chemical_list: D005656:Fungal Proteins; D009821:Oils; D014867:Water; D008049:Lipase