2PX3

Crystal structure of FlhF complexed with GTP/Mg(2+)

2PX3 の概要

• エントリーDOI: 10.2210/pdb2px3/pdb
• 関連するPDBエントリー: 2PX0
• 分子名称: Flagellar biosynthesis protein flhF, MAGNESIUM ION, GUANOSINE-5'-TRIPHOSPHATE, ... (4 entities in total)
• 機能のキーワード: srp gtpase, flagellum, protein transport, biosynthetic protein
• 由来する生物種: Bacillus subtilis
• 細胞内の位置: Cell membrane; Peripheral membrane protein; Cytoplasmic side (By similarity): Q01960
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 33979.67

構造登録者

Bange, G.,Wild, K.,Sinning, I. (登録日: 2007-05-14, 公開日: 2007-09-25, 最終更新日: 2024-04-03)

主引用文献

Bange, G.,Petzold, G.,Wild, K.,Parlitz, R.O.,Sinning, I.
The crystal structure of the third signal-recognition particle GTPase FlhF reveals a homodimer with bound GTP.
Proc.Natl.Acad.Sci.Usa, 104:13621-13625, 2007

PubMed Abstract: Flagella are well characterized as the organelles of locomotion and allow bacteria to react to environmental changes. The assembly of flagella is a multistep process and relies on a complex type III export machinery located in the cytoplasmic membrane. The FlhF protein is essential for the placement and assembly of polar flagella and has been classified as a signal-recognition particle (SRP)-type GTPase. SRP GTPases appeared early in evolution and form a unique subfamily within the guanine nucleotide binding proteins with only three members: the signal sequence-binding protein SRP54, the SRP receptor FtsY, and FlhF. We report the crystal structures of FlhF from Bacillus subtilis in complex with GTP and GMPPNP. FlhF shares SRP GTPase-specific features such as the presence of an N-terminal alpha-helical domain and the I-box insertion. It forms a symmetric homodimer sequestering a composite active site that contains two head-to-tail arranged nucleotides similar to the heterodimeric SRP-targeting complex. However, significant differences to the GTPases of SRP and the SRP receptor include the formation of a stable homodimer with GTP as well as severe modifications and even the absence of motifs involved in regulation of the other two SRP GTPases. Our results provide insights into SRP GTPases and their roles in two fundamentally different protein-targeting routes that both rely on efficient protein delivery to a secretion channel.

PubMed: 17699634
DOI: 10.1073/pnas.0702570104

実験手法

X-RAY DIFFRACTION (3.2 Å)