3CZP

Crystal structure of putative polyphosphate kinase 2 from Pseudomonas aeruginosa PA01

3CZP の概要

• エントリーDOI: 10.2210/pdb3czp/pdb
• 分子名称: Putative polyphosphate kinase 2, ACETATE ION, 1,2-ETHANEDIOL, ... (6 entities in total)
• 機能のキーワード: ppk2, polyphosphate kinase, kinase, mcsg, psi-2, structural genomics, protein structure initiative, midwest center for structural genomics, transferase
• 由来する生物種: Pseudomonas aeruginosa PAO1
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 119008.08

構造登録者

Nocek, B.,Evdokimova, E.,Osipiuk, J.,Savchenko, A.,Edwards, A.M.,Joachimiak, A.,Midwest Center for Structural Genomics (MCSG) (登録日: 2008-04-29, 公開日: 2008-07-01, 最終更新日: 2024-10-30)

主引用文献

Nocek, B.,Kochinyan, S.,Proudfoot, M.,Brown, G.,Evdokimova, E.,Osipiuk, J.,Edwards, A.M.,Savchenko, A.,Joachimiak, A.,Yakunin, A.F.
Polyphosphate-dependent synthesis of ATP and ADP by the family-2 polyphosphate kinases in bacteria.
Proc.Natl.Acad.Sci.USA, 105:17730-17735, 2008

PubMed Abstract: Inorganic polyphosphate (polyP) is a linear polymer of tens or hundreds of phosphate residues linked by high-energy bonds. It is found in all organisms and has been proposed to serve as an energy source in a pre-ATP world. This ubiquitous and abundant biopolymer plays numerous and vital roles in metabolism and regulation in prokaryotes and eukaryotes, but the underlying molecular mechanisms for most activities of polyP remain unknown. In prokaryotes, the synthesis and utilization of polyP are catalyzed by 2 families of polyP kinases, PPK1 and PPK2, and polyphosphatases. Here, we present structural and functional characterization of the PPK2 family. Proteins with a single PPK2 domain catalyze polyP-dependent phosphorylation of ADP to ATP, whereas proteins containing 2 fused PPK2 domains phosphorylate AMP to ADP. Crystal structures of 2 representative proteins, SMc02148 from Sinorhizobium meliloti and PA3455 from Pseudomonas aeruginosa, revealed a 3-layer alpha/beta/alpha sandwich fold with an alpha-helical lid similar to the structures of microbial thymidylate kinases, suggesting that these proteins share a common evolutionary origin and catalytic mechanism. Alanine replacement mutagenesis identified 9 conserved residues, which are required for activity and include the residues from both Walker A and B motifs and the lid. Thus, the PPK2s represent a molecular mechanism, which potentially allow bacteria to use polyP as an intracellular energy reserve for the generation of ATP and survival.

PubMed: 19001261
DOI: 10.1073/pnas.0807563105

実験手法

X-RAY DIFFRACTION (2 Å)