TY  - JOUR
AU  - Li, Dian-Xiang 
AU  - Du, Xin-Jun 
AU  - Zhao, Xiao-Fan 
AU  - Wang, Jin-Xing 
PY  - 2010
TI  - Expression, Purification and Activity Assay of the Recombinant Protein of Catechol-O-Methyltransferase from Chinese White Shrimp (Fenneropenaeus chinensis)
JF  - American Journal of Biochemistry and Biotechnology
VL  - 6
IS  - 3
DO  - 10.3844/ajbbsp.2010.148.154
UR  - https://thescipub.com/abstract/ajbbsp.2010.148.154
AB  - Problem statement: We have previously cloned a gene of Chinese white shrimp Catechol
O-Methyltransferase (designated Fc-COMT) and characterized the gene expression pattern. In this
study, expression and purification as well as activity assay of the recombinant Fc-COMT was further
conducted. Approach: Using pET-30a (+) as a prokaryotic expression vector, the recombinant Fc-
COMT was expressed in the supernatant of Escherichia coli lysate and easily purified by His-Bind
resin chromatography. SDS-PAGE analysis showed that the molecular mass of recombinant Fc-COMT
was approximately 30,000 Da, in good agreement with the software-predicted molecular weight. The
enzymatic activity of recombinant Fc-COMT was tested using Dihydroxybenzoic Acid (DHBAc) as a
substrate. Results: The methyl products of DHBAc, Vanillic Acid (VA) and Isovanillic Acid (IVA),
were detected in the enzymatic reaction mixture with recombinant Fc-COMT by High Performance
Liquid Chromatography-Mass Spectrometry (HPLC-MS). Conclusion: The recombinant Fc-COMT
has catalytic activity of transferring methyl group from S-Adenosyl-L-Methionine (SAM) to the 3' hydroxyl or 4' hydroxyl group of benzyl ring of DHBAc.