Homology modeling and site-directed mutagenesis of caffeic acid-3-O-methyltransferase from Ligusticum chuanxiong
10.7501/j.issn.0253-2670.2016.20.020
- Author:
Ji-Hua YU
1
Author Information
1. School of Life Science and Engineering, Southwest Jiaotong University
- Publication Type:Journal Article
- Keywords:
Caffeic acid-3-O-methyltransferase;
Ferulic acid;
Homology modeling;
Ligusticum chuanxiong Hort.;
Site-directed mutagenesis
- From:
Chinese Traditional and Herbal Drugs
2016;47(20):3677-3682
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To construct the three dimensional models of L. chuanxiong caffeic acid-3-O-methyltransferase (LCCOMT) and verify the model using site-directed mutagenesis technology. Methods: The three-dimensional model was constructed by homology modeling using the crystal structure of COMT from Medicago sativa as a temple. Caffeic acid was docked into the optimized model of LCCOMT to predict the active site. The predicted site was mutated using site-directed mutagenesis technology. Then, the activity of mutant enzyme was detected. Results: The molecular docking, which showed there were hydrogen bonds between His268 and 3-OH of caffeic acid, was successful. Two mutant enzymes, H268N and H268Q, lost 94.85% and 95.28% of their activity respectively. Conclusion: The His268 is confirmed as one of the key residues of LCCOMT. It may play a role as a base in the deprotonation reaction of the 3-OH of caffeic acid.
