title: Solution NMR structure and functional analysis of the integral membrane protein YgaP from Escherichia coli.
abstract: The solution NMR structure of the α-helical integral membrane protein YgaP from Escherichia coli in mixed 1,2-diheptanoyl-sn-glycerol-3-phosphocholine/1-myristoyl-2-hydroxy-sn-glycero-3-phospho-(1'-rac-glycerol) micelles is presented. In these micelles, YgaP forms a homodimer with the two transmembrane helices being the dimer interface, whereas the N-terminal cytoplasmic domain includes a rhodanese-fold in accordance to its sequence homology to the rhodanese family of sulfurtransferases. The enzymatic sulfur transfer activity of full-length YgaP as well as of the N-terminal rhodanese domain only was investigated performing a series of titrations with sodium thiosulfate and potassium cyanide monitored by NMR and EPR. The data indicate the thiosulfate concentration-dependent addition of several sulfur atoms to the catalytic Cys-63, which process can be reversed by the addition of potassium cyanide. The catalytic reaction induces thereby conformational changes within the rhodanese domain, as well as on the transmembrane α-helices of YgaP. These results provide insights into a potential mechanism of YgaP during the catalytic thiosulfate activity in vivo.
authors: From the Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland and.
authors: Cédric
authors: C
authors: Eichmann
authors: From the Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland and the Structural Biology Laboratory, The Salk Institute, La Jolla, California 92037.
authors: Christos
authors: C
authors: Tzitzilonis
authors: From the Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland and.
authors: Enrica
authors: E
authors: Bordignon
authors: the Structural Biology Laboratory, The Salk Institute, La Jolla, California 92037.
authors: Innokentiy
authors: I
authors: Maslennikov
authors: the Structural Biology Laboratory, The Salk Institute, La Jolla, California 92037.
authors: Senyon
authors: S
authors: Choe
authors: From the Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland and the Structural Biology Laboratory, The Salk Institute, La Jolla, California 92037 roland.riek@phys.chem.ethz.ch.
authors: Roland
authors: R
authors: Riek
mesh_terms: D004926:Escherichia coli / Q000737:chemistry*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000502:physiology*; D008565:Membrane Proteins / Q000737:chemistry* / Q000502:physiology*; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011487:Protein Conformation; D013329:Structure-Activity Relationship; D013884:Thiosulfate Sulfurtransferase / Q000737:chemistry
chemical_list: D029968:Escherichia coli Proteins; D008565:Membrane Proteins; C530142:YgaP protein, E coli; D013884:Thiosulfate Sulfurtransferase
keywords: Enzyme Catalysis; Membrane Enzyme; Membrane Protein; Nuclear Magnetic Resonance (NMR); Rhodanese; Structural Biology; Sulfotransferase; Sulfurtransferase; Three-dimensional Structure