QQ客服 官方微博 反馈留言

	The roles of C-terminal loop residues of dimeric arginine kinase from sea cucumber Stichopus japonicus in catalysis, specificity and structure
	Zhang, HW ; Zhao, TJ ; Wang, SL ; Guo, Q ; Liu, TT ; Zhao, F ; Wang, XC
	2010-05-11 ; 2010-05-11
关键词	phosphagen kinase conformation N-loop MUSCLE CREATINE-KINASE AMINO-ACID-RESIDUES ADENOSINE TRIPHOSPHATE MECHANISM PHOSPHOTRANSFERASE PURIFICATION SITE INACTIVATION MUTAGENESIS BINDING Biochemistry & Molecular Biology
中文摘要	Arginine kinase (AK) catalyzes the reversible phosphorylation of arginine by MgATP to form a high-energy compound phosphoarginine (Parg) and M ADP in forward reaction in invertebrates. To detect the different catalytical mechanisms among Stichopus-AK (dimer) and Limulus-AK (monomer) and Torpedo creatine kinase (dimeric CK) and to reveal the structural role of the C-terminal domain loop (C-loop) of dimeric AK, six single-site mutants. E314D, E314Q, E314V, F315A, F315H and F315Y were constructed as well as two multi-site variants, S312R/F315H/V319E (formed by substituting the C-loop of monomeric AK for that of dimeric AK, termed the AAloop) and S312G/E314V/F315D/E317A/S318A/G321S (formed by substituting the C-loop of dimeric CK for that of dimeric AK, termed the ACloop). The AK activity of the three mutants at Glu(314) decreased significantly. from 60- to 500-fold. The ACloop showed only slight AK activity, unlike the same construction in Limulus-AK. In addition, all Phe(315) mutants including the AAloop which retained Glu(314) had modest AK activity (5-84% of the wild type). All the results above suggested that Glu(314) played a more significant role in catalysis in dimeric AK than in the monomer. In addition, ANS profiles indicated that the tolerance of the three Glu(314) mutants to denaturant decreased slightly compared with wild type AK. Though monomeric AK has a His residue at site 315, mutants F315H and the AAloop Could not resist any perturbation of denaturant, and the mutants showed a Gibbs free energy of about 2.7 kJ/mol lower than wild type AK. Therefore Phe(315) in dimeric AK has a different role from His(315) in monomeric AK. This might contribute to the stabilization of the native conformation. while His(315) in Limulus AK directly binded to the carboxylate of arginine. Taking all the results above together, we suggested a unique mechanism in dimeric AK, different from both monomeric AK and dimeric CK. (c) 2006 Elsevier B.V. All rights reserved.
语种	英语 ; 英语
出版者	ELSEVIER SCIENCE BV ; AMSTERDAM ; PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
内容类型	期刊论文
源URL	[http://hdl.handle.net/123456789/26806]
专题	清华大学
推荐引用方式 GB/T 7714	Zhang, HW,Zhao, TJ,Wang, SL,et al. The roles of C-terminal loop residues of dimeric arginine kinase from sea cucumber Stichopus japonicus in catalysis, specificity and structure[J],2010, 2010.
APA	Zhang, HW.,Zhao, TJ.,Wang, SL.,Guo, Q.,Liu, TT.,...&Wang, XC.(2010).The roles of C-terminal loop residues of dimeric arginine kinase from sea cucumber Stichopus japonicus in catalysis, specificity and structure..
MLA	Zhang, HW,et al."The roles of C-terminal loop residues of dimeric arginine kinase from sea cucumber Stichopus japonicus in catalysis, specificity and structure".(2010).

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。