ATPase / T4P / type iv pilus / motor / MOTOR PROTEIN
機能・相同性
Pilus retraction protein PilT/PilU / Bacterial type II secretion system protein E signature. / Type II/IV secretion system protein / Type II/IV secretion system protein / P-loop containing nucleoside triphosphate hydrolase / ATP binding / metal ion binding / Twitching motility pilus retraction ATPase
ジャーナル: Nat Commun / 年: 2019 タイトル: Multiple conformations facilitate PilT function in the type IV pilus. 著者: Matthew McCallum / Samir Benlekbir / Sheryl Nguyen / Stephanie Tammam / John L Rubinstein / Lori L Burrows / P Lynne Howell / 要旨: Type IV pilus-like systems are protein complexes that polymerize pilin fibres. They are critical for virulence in many bacterial pathogens. Pilin polymerization and depolymerization are powered by ...Type IV pilus-like systems are protein complexes that polymerize pilin fibres. They are critical for virulence in many bacterial pathogens. Pilin polymerization and depolymerization are powered by motor ATPases of the PilT/VirB11-like family. This family is thought to operate with C symmetry; however, most of these ATPases crystallize with either C or C symmetric conformations. The relevance of these conformations is unclear. Here, we determine the X-ray structures of PilT in four unique conformations and use these structures to classify the conformation of available PilT/VirB11-like family member structures. Single particle electron cryomicroscopy (cryoEM) structures of PilT reveal condition-dependent preferences for C C, and C conformations. The physiologic importance of these conformations is validated by coevolution analysis and functional studies of point mutants, identifying a rare gain-of-function mutation that favours the C conformation. With these data, we propose a comprehensive model of PilT function with broad implications for PilT/VirB11-like family members.