5EXT

AAA+ domain of FleQ from Pseudomonas aeruginosa bound to ADP

Summary for 5EXT

• Entry DOI: 10.2210/pdb5ext/pdb
• Related: 5EXP 5EXS 5EXX
• Descriptor: Transcriptional regulator FleQ, ADENOSINE-5'-DIPHOSPHATE (3 entities in total)
• Functional Keywords: transcription factor, aaa+, atpase, c-di-gmp, transcription
• Biological source: Pseudomonas aeruginosa
• Total number of polymer chains: 1
• Total formula weight: 29727.89

Authors

Navarro, M.V.A.S.,Sondermann, H.,Matsuyama, B.Y. (deposition date: 2015-11-24, release date: 2016-01-13, Last modification date: 2023-09-27)

Primary citation

Matsuyama, B.Y.,Krasteva, P.V.,Baraquet, C.,Harwood, C.S.,Sondermann, H.,Navarro, M.V.
Mechanistic insights into c-di-GMP-dependent control of the biofilm regulator FleQ from Pseudomonas aeruginosa.
Proc.Natl.Acad.Sci.USA, 113:E209-E218, 2016

PubMed Abstract: Bacterial biofilm formation during chronic infections confers increased fitness, antibiotic tolerance, and cytotoxicity. In many pathogens, the transition from a planktonic lifestyle to collaborative, sessile biofilms represents a regulated process orchestrated by the intracellular second-messenger c-di-GMP. A main effector for c-di-GMP signaling in the opportunistic pathogen Pseudomonas aeruginosa is the transcription regulator FleQ. FleQ is a bacterial enhancer-binding protein (bEBP) with a central AAA+ ATPase σ(54)-interaction domain, flanked by a C-terminal helix-turn-helix DNA-binding motif and a divergent N-terminal receiver domain. Together with a second ATPase, FleN, FleQ regulates the expression of flagellar and exopolysaccharide biosynthesis genes in response to cellular c-di-GMP. Here we report structural and functional data that reveal an unexpected mode of c-di-GMP recognition that is associated with major conformational rearrangements in FleQ. Crystal structures of FleQ's AAA+ ATPase domain in its apo-state or bound to ADP or ATP-γ-S show conformations reminiscent of the activated ring-shaped assemblies of other bEBPs. As revealed by the structure of c-di-GMP-complexed FleQ, the second messenger interacts with the AAA+ ATPase domain at a site distinct from the ATP binding pocket. c-di-GMP interaction leads to active site obstruction, hexameric ring destabilization, and discrete quaternary structure transitions. Solution and cell-based studies confirm coupling of the ATPase active site and c-di-GMP binding, as well as the functional significance of crystallographic interprotomer interfaces. Taken together, our data offer unprecedented insight into conserved regulatory mechanisms of gene expression under direct c-di-GMP control via FleQ and FleQ-like bEBPs.

PubMed: 26712005
DOI: 10.1073/pnas.1523148113

Experimental method

X-RAY DIFFRACTION (2.4 Å)