Crystal structures of the kinase domain of PpkA, a key regulatory component of T6SS, reveal a general inhibitory mechanism

doi:10.1042/BCJ20180077

CORC > 上海应用物理研究所 > 中国科学院上海应用物理研究所 > 中科院上海应用物理研究所2011-2017年

	Crystal structures of the kinase domain of PpkA, a key regulatory component of T6SS, reveal a general inhibitory mechanism
	Li, PP ; Xu, DQ ; Ma, TQ ; Wang, DY ; Li, WD ; He, JH ; Ran, TT ; Wang, WW
刊名	BIOCHEMICAL JOURNAL
	2018
卷号	475 期号:-页码:2209-2224
关键词	VI SECRETION SYSTEM DEPENDENT PROTEIN-KINASE GRAM-NEGATIVE BACTERIA MYCOBACTERIUM-TUBERCULOSIS SERINE/THREONINE KINASE CATALYTIC DOMAIN CONFORMATIONAL PLASTICITY PSEUDOMONAS-AERUGINOSA ACTIVATION MECHANISM EDWARDSIELLA-TARDA
ISSN号	0264-6021
DOI	10.1042/BCJ20180077
文献子类	期刊论文
英文摘要	The type VI secretion system (T6SS) is a versatile and widespread export system found in many Gram-negative bacteria that delivers effector proteins into target cells. The functions of T6SSs are tightly regulated by diverse mechanisms at multiple levels, including post-translational modification through threonine phosphorylation via the Ser/Thr protein kinase (STPK) PpkA. Here, we identified that PpkA is essential for T6SS secretion in Serratia marcescens since its deletion eliminated the secretion of haemolysin co-regulated protein, while the periplasmic and transmembrane portion of PpkA was found to be disposable for T6SS secretion. We further determined the crystal structure of the kinase domain of PpkA (PpkA-294). The structure of PpkA-294 was determined in its apo form to a 1.6 angstrom resolution as well as in complex with ATP to a 1.41 angstrom resolution and with an ATP analogue AMP-PCP to a 1.45 angstrom resolution. The residues in the activation loop of PpkA-294 were fully determined, and the N-terminus of the loop was folded into an unprecedented inhibitory helix, revealing that the PpkA kinase domain was in an auto-inhibitory state. The ternary MgATP-PpkA-294 complex was also inactive with nucleotide ribose and phosphates in unexpected and unproductive conformations. The aC-helix in the inactive PpkA-294 adopted a conformation towards the active site but with the conserved glutamate in the helix rotated away, which we suggest to be a general conformation for all STPK kinases in the inactive form. Structural comparison of PpkA with its eukaryotic homologues reinforced the universal regulation mechanism of protein kinases.
语种	英语
内容类型	期刊论文
源URL	[http://ir.sinap.ac.cn/handle/331007/30895]
专题	上海应用物理研究所_中科院上海应用物理研究所2011-2017年
作者单位	1.Nanjing Agr Univ, Coll Life Sci, Dept Microbiol, Nanjing 210095, Jiangsu, Peoples R China 2.Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai 201204, Peoples R China 3.Jiangsu Acad Agr Sci, Inst Agr Prod Proc, Nanjing 210014, Jiangsu, Peoples R China
推荐引用方式 GB/T 7714	Li, PP,Xu, DQ,Ma, TQ,et al. Crystal structures of the kinase domain of PpkA, a key regulatory component of T6SS, reveal a general inhibitory mechanism[J]. BIOCHEMICAL JOURNAL,2018,475(-):2209-2224.
APA	Li, PP.,Xu, DQ.,Ma, TQ.,Wang, DY.,Li, WD.,...&Wang, WW.(2018).Crystal structures of the kinase domain of PpkA, a key regulatory component of T6SS, reveal a general inhibitory mechanism.BIOCHEMICAL JOURNAL,475(-),2209-2224.
MLA	Li, PP,et al."Crystal structures of the kinase domain of PpkA, a key regulatory component of T6SS, reveal a general inhibitory mechanism".BIOCHEMICAL JOURNAL 475.-(2018):2209-2224.