Theoretical Investigation on the Dissociation of (R)-Benzoin Catalyzed by Benzaldehyde Lyase

NWIPB OpenIR

	Theoretical Investigation on the Dissociation of (R)-Benzoin Catalyzed by Benzaldehyde Lyase
	Zhang, Jing ; Sheng, Xiang ; Hou, QianQian ; Liu, Yongjun
	2014-03-15
发表期刊	INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY ; Zhang, J; Sheng, X; Hou, QQ; Liu, YJ.Theoretical Investigation on the Dissociation of (R)-Benzoin Catalyzed by Benzaldehyde Lyase,INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY,2014,114(6):375
摘要	Benzaldehyde lyase (BAL) is a versatile thiamin diphosphate (THDP)-dependent enzyme with widespread synthetic applications in industry. Besides lyase activity, BAL also performs the functions as carboligase and decarboxylase. Unlike many other THDP-dependent enzymes, the active center of BAL is devoid of any acid-base amino acid residues except Glu50 and His29, and therefore, the catalytic mechanism of BAL is unusual. In this article, the dissociation mechanism of (R)-benzoin to benzaldehyde catalyzed by BAL has been studied by using density functional theory method. The calculation results indicate that the whole reaction consists of four elementary steps, and at least two steps contribute to rate-limiting. A big difference with other THDP-dependent enzymes is that, in the first stage of the reaction, the ligation of substrate and THDP ylide is not companied by proton transfer, and in the subsequent transition states and intermediates, the carbonyl oxygen always exists in the form of anion. Gln113, His29, and 4-amino group of THDP are found to have the function to stabilize the transition states and intermediates. His29 acts as the proton acceptor in step 2 and proton donor in step 3 using one water molecule as mediator. (c) 2013 Wiley Periodicals, Inc.; Benzaldehyde lyase (BAL) is a versatile thiamin diphosphate (THDP)-dependent enzyme with widespread synthetic applications in industry. Besides lyase activity, BAL also performs the functions as carboligase and decarboxylase. Unlike many other THDP-dependent enzymes, the active center of BAL is devoid of any acid-base amino acid residues except Glu50 and His29, and therefore, the catalytic mechanism of BAL is unusual. In this article, the dissociation mechanism of (R)-benzoin to benzaldehyde catalyzed by BAL has been studied by using density functional theory method. The calculation results indicate that the whole reaction consists of four elementary steps, and at least two steps contribute to rate-limiting. A big difference with other THDP-dependent enzymes is that, in the first stage of the reaction, the ligation of substrate and THDP ylide is not companied by proton transfer, and in the subsequent transition states and intermediates, the carbonyl oxygen always exists in the form of anion. Gln113, His29, and 4-amino group of THDP are found to have the function to stabilize the transition states and intermediates. His29 acts as the proton acceptor in step 2 and proton donor in step 3 using one water molecule as mediator. (c) 2013 Wiley Periodicals, Inc.
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/37397
专题	中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	Zhang, Jing,Sheng, Xiang,Hou, QianQian,et al. Theoretical Investigation on the Dissociation of (R)-Benzoin Catalyzed by Benzaldehyde Lyase[J]. INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Zhang, J; Sheng, X; Hou, QQ; Liu, YJ.Theoretical Investigation on the Dissociation of (R)-Benzoin Catalyzed by Benzaldehyde Lyase,INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY,2014,114(6):375,2014.
APA	Zhang, Jing,Sheng, Xiang,Hou, QianQian,&Liu, Yongjun.(2014).Theoretical Investigation on the Dissociation of (R)-Benzoin Catalyzed by Benzaldehyde Lyase.INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY.
MLA	Zhang, Jing,et al."Theoretical Investigation on the Dissociation of (R)-Benzoin Catalyzed by Benzaldehyde Lyase".INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY (2014).