Characterization of a novel aryloxyphenoxypropionate herbicide-hydrolyzing carboxylesterase with R-enantiomer preference from Brevundimonas sp. QPT-2. (July 2019)

• Record Type: Journal Article
• Authors: Xu, Xinyun; Wang, Jiahao; Yu, Ting; Nian, Haohan; Zhang, Hui; Wang, Guangli; Li, Feng
• Is Part Of: Process biochemistry. Volume 82(2019)
• Page Start: 102
• Page End: 109
• Publication Date: 2019-07
• Subjects: Aryloxyphenoxypropionate herbicides -- Enantioselectivity biodegradation -- Brevundimonas sp. -- Carboxylesterase; Biochemical engineering -- Periodicals; Biotechnology -- Periodicals; Biochemistry -- periodicals; Biotechnology -- periodicals; Chemical Engineering -- periodicals; Génie biochimique -- Périodiques; Biotechnologie -- Périodiques; Biochemical engineering; Biotechnology; Periodicals; 660.63
• DOI: 10.1016/j.procbio.2019.03.013
• Languages: English
• ISSNs: 1359-5113

Abstract

Graphical abstract: Highlights: A novel carboxylesterase gene estwx was cloned from Brevundimonas sp. The recombinant EstWX was functionally expressed, purified and characterized. EstWX hydrolyzes a wide range of AOPP herbicides with various catalytic efficiencies. EstWX preferentially transformed R-enantiomer of AOPP herbicides over S-form. The S73, K76, Y196 and W368 residues were essential for EstWX catalytic activity. Abstract: Aryloxyphenoxypropionate (AOPP) herbicides with a chiral center are widely used to selectively remove annual and perennial grasses. However, the study of the enzymes involved in enantioselective degradation of AOPP herbicides is limited. A novel family VIII carboxylesterase gene, estwx, hydrolyzed the ester bond cleavage of AOPP herbicides to form the corresponding acid and alkyl side chain alcohol, was cloned from Brevundimonas sp. strain QPT-2 and overexpressed in E. coli BL21. The purified recombinant EstWX was shown to hydrolyze a wide range of AOPP herbicides with various catalytic efficiencies. The enantioselectivity assay indicated that EstWX preferentially catalyzed the hydrolysis of the R -enantiomer of AOPP herbicides. The S73, K76, Y196 together with W368 residues, especially S73 and Y196, were essential for the catalytic function of the carboxylesterase. EstWX is a promising candidate for the bioremediation of multiple AOPP herbicide-contaminated environments and for future mechanism studies on the enantioselective degradation of chiral AOPP herbicides.