Related Experiment Video
Updated: Jun 19, 2026
Defining Substrate Specificities for Lipase and Phospholipase Candidates
Published on: November 23, 2016
[Cloning, expression and characterization of a novel lipase gene lipB from Aspergillus niger F044]
Jiangke Yang1, Zhengping Zhang, Liyin Liu
1Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China. jiangke.yang@hotmail.com
Objective:
We cloned, expressed and characterized a novel lipase gene lipB from Aspergillus niger F044, to facilitate the large scale production and application of that enzyme.
Method:
We cloned lipB gene and the cDNA sequence by PCR and RT-PCR, and then cloned the open reading frame of lipB into pET28a vector and expressed by isopropyl beta-D-1-thiogalactopyranoside (IPTG) induction. After Ni-agarose purification, the characteristics were determined and the conformation change was checked by circular dichroism methods.
Results:
The novel lipase genes cDNA of lipB were cloned from Aspergillus niger F044 (GenBank: FJ536287, FJ536288) and expressed in Escherichia coli. The molecular weight of LipB was about 43 kDa. The optimal substrate of this enzyme is 4-nitrophenyl octanoate (pNPC-C8) with Km = 5.98 mmol/L. The optimal temperature and pH was 50 degrees C and pH 6.0. The enzyme was stable below 40 degrees C. After incubated at 60 degrees C for 1 h, only 18.8% activity remained. After treated by 2 mmol/L Ca2+ for 1 h, the activity improved 2.6-fold.
Conclusion:
Enzymatic characteristics of LipB determined showed this enzyme might have potential in industrial applications.
