Insights into the molecular mechanism of dehalogenation catalyzed by D-2-haloacid dehalogenase from crystal structures

doi:10.1038/s41598-017-19050-x

	Insights into the molecular mechanism of dehalogenation catalyzed by D-2-haloacid dehalogenase from crystal structures
	Wang, Yayue 1,2; Feng, Yanbin 1; Cao, Xupeng 1; Liu, Yinghui 1; Xue, Song 1
刊名	SCIENTIFIC REPORTS
	2018-01-23
卷号	8
ISSN号	2045-2322
DOI	10.1038/s41598-017-19050-x
文献子类	Article
英文摘要	D-2-haloacid dehalogenases (D-DEXs) catalyse the hydrolytic dehalogenation of D-2-haloacids, releasing halide ions and producing the corresponding 2-hydroxyacids. A structure-guided elucidation of the catalytic mechanism of this dehalogenation reaction has not been reported yet. Here, we report the catalytic mechanism of a D-DEX, HadD AJ1 from Pseudomonas putida AJ1/23, which was elucidated by X-ray crystallographic analysis and the H-2 O-18 incorporation experiment. HadD AJ1 is an a-helical hydrolase that forms a homotetramer with its monomer including two structurally axisymmetric repeats. The product-bound complex structure was trapped with L-lactic acid in the active site, which is framed by the structurally related helices between two repeats. Site-directed mutagenesis confirmed the importance of the residues lining the binding pocket in stabilizing the enzyme-substrate complex. Asp205 acts as a key catalytic residue and is responsible for activating a water molecule along with Asn131. Then, the hydroxyl group of the water molecule directly attacks the C2 atom of the substrate to release the halogen ion instead of forming an enzyme-substrate ester intermediate as observed in L-2-haloacid dehalogenases. The newly revealed structural and mechanistic information on D-DEX may inspire structure-based mutagenesis to engineer highly efficient haloacid dehalogenases.
WOS关键词	PUTIDA STRAIN AJ1/23 ; DL-2-HALOACID DEHALOGENASE ; L-2-HALOACID DEHALOGENASE ; PURIFICATION ; FOLD ; YL
WOS研究方向	Science & Technology - Other Topics
语种	英语
出版者	NATURE PUBLISHING GROUP
WOS记录号	WOS:000423045400027
内容类型	期刊论文
源URL	[http://cas-ir.dicp.ac.cn/handle/321008/168520]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
通讯作者	Xue, Song
作者单位	1.Chinese Acad Sci, Dalian Inst Chem Phys, Marine Bioengn Grp, Dalian 116023, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Wang, Yayue,Feng, Yanbin,Cao, Xupeng,et al. Insights into the molecular mechanism of dehalogenation catalyzed by D-2-haloacid dehalogenase from crystal structures[J]. SCIENTIFIC REPORTS,2018,8.
APA	Wang, Yayue,Feng, Yanbin,Cao, Xupeng,Liu, Yinghui,&Xue, Song.(2018).Insights into the molecular mechanism of dehalogenation catalyzed by D-2-haloacid dehalogenase from crystal structures.SCIENTIFIC REPORTS,8.
MLA	Wang, Yayue,et al."Insights into the molecular mechanism of dehalogenation catalyzed by D-2-haloacid dehalogenase from crystal structures".SCIENTIFIC REPORTS 8(2018).