Environment-induced conformational and functional changes of L-2-haloacid dehalogenase.
2-Haloacid dehalogenases have been highly studied due to their potential applications in chemical industries and bioremediation. Although biochemical and structural characterizations of the enzyme have been detailed, no information was available regarding environmental effects on the structure-function relationship. Here, circular dichroism spectroscopy (CD) was used to investigate the correlation between changes on the conformation and the function of l-2-haloacid dehalogenase (HadL AJ1) from the Pseudomonas putida induced by the environmental factors. Decreased α-helix and increased β-sheet contents were observed in the structure of HadL AJ1 along with activity losses caused by pH, temperature and inhibitors. Regardless of which factor above-mentioned existed, more than 65.0% of HadL AJ1 activity could be remained if its α-helix content was over 12.0%. The maintenance of α-helical structure in HadL AJ1 was indispensable to its catalysis, while β-sheet increase restricts its activity. This study revealed the variation of enzymatic activity due to environmental conditions resulting in structural changes monitored by CD, which contributed to rational modification and was instructive for predicting changes of the enzymatic activity during application.
Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China; School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
Yayue
Y
Wang
Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Xupeng
X
Cao
Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Yanbin
Y
Feng
Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China. Electronic address: xuesong@dicp.ac.cn.
Song
S
Xue
D055162:Biocatalysis / Q000187:drug effects; D002942:Circular Dichroism; D004777:Environment; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D006867:Hydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism*; D017433:Protein Structure, Secondary / Q000187:drug effects; D016958:Pseudomonas putida / Q000201:enzymology*; D013696:Temperature
D004791:Enzyme Inhibitors; D006867:Hydrolases; C034507:2-haloacid dehalogenase
Circular dichroism; Conformation; Environmental effects; l-2-Haloacid dehalogenase