title: Cloning, purification, crystallization and X-ray crystallographic analysis of the periplasmic sensing domain of Pseudomonas fluorescens chemotactic transducer of amino acids type A (CtaA).
abstract: Chemotaxis towards nutrients plays a crucial role in root colonization by Pseudomonas fluorescens. The P. fluorescens chemotactic transducer of amino acids type A (CtaA) mediates movement towards amino acids present in root exudates. In this study, the periplasmic sensory domain of CtaA has been crystallized by the hanging-drop vapor diffusion method using ammonium sulfate as a precipitating agent. A complete data set was collected to 1.9 Å resolution using cryocooling conditions and synchrotron radiation. The crystals belong to space group I222 or I212121, with unit-cell parameters a = 67.2, b = 76.0, c = 113.3 Å. This is an important step towards elucidation of the structural basis of how CtaA recognizes its signal molecules and transduces the signal across the membrane.
authors.affiliation: Infection and Immunity Program, Monash Biomedicine Discovery Institute, Australia; Department of Microbiology, Monash University.
authors.forename: Abu Iftiaf Md Salah
authors.initials: AI
authors.lastname: Ud-Din
authors.forename: Anna
authors.initials: A
authors.lastname: Roujeinikova
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D002633:Chemotaxis / Q000235:genetics*; D003001:Cloning, Molecular; D003460:Crystallization / Q000379:methods; D018360:Crystallography, X-Ray; D003573:Cytochrome b Group / Q000737:chemistry* / Q000302:isolation & purification; D008565:Membrane Proteins / Q000737:chemistry* / Q000302:isolation & purification; D018517:Plant Roots / Q000382:microbiology; D000072417:Protein Domains; D011551:Pseudomonas fluorescens / Q000737:chemistry*; D015398:Signal Transduction
chemical_list: D001426:Bacterial Proteins; C090098:CtaA protein, bacteria; D003573:Cytochrome b Group; D008565:Membrane Proteins