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7603387 
Journal Article 
Cloning, characterization and expression of the extracellular lipase gene from Aureobasidium pullulans HN2-3 isolated from sea saltern 
Liu, Z; Li, X; Chi, Z; Wang, L; Li, J; Wang, X 
2008 
Yes 
Antonie van Leeuwenhoek
ISSN: 0003-6072
EISSN: 1572-9699 
94 
2 
245-255 
English 
18340544 
The extracellular lipase structural gene was isolated from cDNA of Aureobasidium pullulans HN2-3 by using SMART(TM) RACE cDNA amplification kit. The gene had an open reading frame of 1245 bp long encoding a lipase. The coding region of the gene was interrupted by only one intron (55 bp). It encodes 414 amino acid residues of a protein with a putative signal peptide of 26 amino acids. The protein sequence deduced from the extracellular lipase structural gene contained the lipase consensus sequence (G-X-S-X-G) and three conserved putative N-glycosylation sites. According to the phylogenetic tree of the lipases, the lipase from A. pullulans was closely related to that from Aspergillus fumigatus (XP_750543) and Neosartorya fischeri (XP_001257768) and the identities were 50% and 52%, respectively. The mature peptide encoding cDNA was subcloned into pET-24a (+) expression vector. The recombinant plasmid was expressed in Escherichia coli BL21(DE3). The expressed fusion protein was analyzed by SDS-PAGE and western blotting and a specific band with molecular mass of about 47 kDa was found. Enzyme activity assay verified the recombinant protein as a lipase. A maximum activity of 0.96 U/mg was obtained from cellular extract of E. coli BL21(DE3) harboring pET-24a(+)LIP1. Optimal pH and temperature of the crude recombinant lipase were 8.0 and 35 degrees C, respectively and the crude recombinant lipase had the highest hydrolytic activity towards peanut oil.