title: Molecular Insights into Toluene Sensing in the TodS/TodT Signal Transduction System.
abstract: TodS is a sensor kinase that responds to various monoaromatic compounds, which either cause an agonistic or antagonistic effect on phosphorylation of its cognate response regulator TodT, and controls tod operon expression in Pseudomonas putida strains. We describe a molecular sensing mechanism of TodS that is activated in response to toluene. The crystal structures of the TodS Per-Arnt-Sim (PAS) 1 sensor domain (residues 43-164) and its complex with toluene (agonist) or 1,2,4-trimethylbenzene (antagonist) show a typical β2α3β3 PAS fold structure (residues 45-149), forming a hydrophobic ligand-binding site. A signal transfer region (residues 150-163) located immediately after the canonical PAS fold may be intrinsically flexible and disordered in both apo-PAS1 and antagonist-bound forms and dramatically adapt an α-helix upon toluene binding. This structural change in the signal transfer region is proposed to result in signal transmission to activate the TodS/TodT two-component signal transduction system. Site-directed mutagenesis and β-galactosidase assays using a P. putida reporter strain system verified the essential residues involved in ligand sensing and signal transfer and suggest that the Phe(46) residue acts as a ligand-specific switch.
authors.affiliation: From the Infection and Immunity Research Center, skohtn@kribb.re.kr.
authors.forename: Serry
authors.initials: S
authors.lastname: Koh
authors.affiliation: From the Infection and Immunity Research Center.
authors.forename: Jungwon
authors.initials: J
authors.lastname: Hwang
authors.affiliation: From the Infection and Immunity Research Center, the Biosystems and Bioengineering Program, University of Science and Technology, Daejeon 305-350, Korea.
authors.forename: Koushik
authors.initials: K
authors.lastname: Guchhait
authors.affiliation: the Biosystems and Bioengineering Program, University of Science and Technology, Daejeon 305-350, Korea the Biochemicals and Synthetic Biology Research Center, and.
authors.forename: Eun-Gyeong
authors.initials: EG
authors.lastname: Lee
authors.affiliation: the Biochemicals and Synthetic Biology Research Center, and.
authors.forename: Sang-Yoon
authors.initials: SY
authors.lastname: Kim
authors.affiliation: the Biochemicals and Synthetic Biology Research Center, and.
authors.forename: Sujin
authors.initials: S
authors.lastname: Kim
authors.affiliation: the Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, Gangwon-do 200-701, Korea, and.
authors.forename: Sangmin
authors.initials: S
authors.lastname: Lee
authors.affiliation: the Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, Gangwon-do 200-701, Korea, and.
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Chung
authors.affiliation: the Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, Gangwon-do 200-701, Korea, and.
authors.forename: Hyun Suk
authors.initials: HS
authors.lastname: Jung
authors.affiliation: From the Infection and Immunity Research Center, the Biosystems and Bioengineering Program, University of Science and Technology, Daejeon 305-350, Korea.
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: the Biosystems and Bioengineering Program, University of Science and Technology, Daejeon 305-350, Korea the Molecular Phytobacteriology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea.
authors.forename: Choong-Min
authors.initials: CM
authors.lastname: Ryu
authors.affiliation: the Biosystems and Bioengineering Program, University of Science and Technology, Daejeon 305-350, Korea the Biochemicals and Synthetic Biology Research Center, and.
authors.forename: Seung-Goo
authors.initials: SG
authors.lastname: Lee
authors.affiliation: From the Infection and Immunity Research Center, the Biosystems and Bioengineering Program, University of Science and Technology, Daejeon 305-350, Korea.
authors.forename: Tae-Kwang
authors.initials: TK
authors.lastname: Oh
authors.affiliation: the Biosystems and Bioengineering Program, University of Science and Technology, Daejeon 305-350, Korea the Biochemicals and Synthetic Biology Research Center, and oskwon@kribb.re.kr.
authors.forename: Ohsuk
authors.initials: O
authors.lastname: Kwon
authors.affiliation: From the Infection and Immunity Research Center, the Biosystems and Bioengineering Program, University of Science and Technology, Daejeon 305-350, Korea mhk8n@kribb.re.kr.
authors.forename: Myung Hee
authors.initials: MH
authors.lastname: Kim
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018360:Crystallography, X-Ray; D009876:Operon; D017510:Protein Folding; D011494:Protein Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D016958:Pseudomonas putida / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D014050:Toluene / Q000737:chemistry / Q000378:metabolism; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; C104650:TodT protein, Pseudomonas putida; D015534:Trans-Activators; D014050:Toluene; D011494:Protein Kinases; C104649:TodS protein, Pseudomonas putida
keywords: Pseudomonas; bacterial signal transduction; biodegradation; histidine kinase; x-ray crystallography