Computational studies on the catalytic mechanism of phosphoketolase

NWIPB OpenIR

	Computational studies on the catalytic mechanism of phosphoketolase
	Zhang, Jing ; Liu, Yongjun ; Liu, YJ (reprint author), Shandong Univ, Sch Chem & Chem Engn, Jinan 250100, Shandong, Peoples R China.
	2013-12-01
发表期刊	COMPUTATIONAL AND THEORETICAL CHEMISTRY ; Zhang, J; Liu, YJ.Computational studies on the catalytic mechanism of phosphoketolase,COMPUTATIONAL AND THEORETICAL CHEMISTRY,2013,1025():1-7
摘要	Phosphoketolase (PK) is a thiamine diphosphate (THDP) dependent enzyme which plays key roles in the metabolism of heterofermentative bacteria. By using density functional theory (DFT) method, the catalytic mechanism of PK has been studied on simplified models. The calculation results indicate hat the formation of 2-alpha,beta-dihydroxyethylidene-THDP (DHETHDP) and erythrose-4-phosphate (E4P) involves one C-C bond formation and one C-C bond cleavage process. Each C-C bond formation or cleavage is always accompanied by a proton transfer in a concerted but asynchronous way. The dehydration process in the reaction of PK is distinct from that of other THDP-dependent enzymes. The Keto-Enol tautomerism process is assisted with a mediator His553. His64, His553 and His97 are found to have the function to stabilize the transition states and intermediates. His64 is a better candidate of B1 catalyst. His553 acts as a proton donor to protonate the carbonyl oxygen, and plays intermediary role in the Keto-Enol tautomerism process. His97 is the probable B2 catalyst in the dehydration process. (C) 2013 Elsevier B.V. All rights reserved.; Phosphoketolase (PK) is a thiamine diphosphate (THDP) dependent enzyme which plays key roles in the metabolism of heterofermentative bacteria. By using density functional theory (DFT) method, the catalytic mechanism of PK has been studied on simplified models. The calculation results indicate hat the formation of 2-alpha,beta-dihydroxyethylidene-THDP (DHETHDP) and erythrose-4-phosphate (E4P) involves one C-C bond formation and one C-C bond cleavage process. Each C-C bond formation or cleavage is always accompanied by a proton transfer in a concerted but asynchronous way. The dehydration process in the reaction of PK is distinct from that of other THDP-dependent enzymes. The Keto-Enol tautomerism process is assisted with a mediator His553. His64, His553 and His97 are found to have the function to stabilize the transition states and intermediates. His64 is a better candidate of B1 catalyst. His553 acts as a proton donor to protonate the carbonyl oxygen, and plays intermediary role in the Keto-Enol tautomerism process. His97 is the probable B2 catalyst in the dehydration process. (C) 2013 Elsevier B.V. All rights reserved.
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/42146
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,Liu, Yongjun,Liu, YJ . Computational studies on the catalytic mechanism of phosphoketolase[J]. COMPUTATIONAL AND THEORETICAL CHEMISTRY, Zhang, J; Liu, YJ.Computational studies on the catalytic mechanism of phosphoketolase,COMPUTATIONAL AND THEORETICAL CHEMISTRY,2013,1025():1-7,2013.
APA	Zhang, Jing,Liu, Yongjun,&Liu, YJ .(2013).Computational studies on the catalytic mechanism of phosphoketolase.COMPUTATIONAL AND THEORETICAL CHEMISTRY.
MLA	Zhang, Jing,et al."Computational studies on the catalytic mechanism of phosphoketolase".COMPUTATIONAL AND THEORETICAL CHEMISTRY (2013).