title: Nitrosylation of Nitric-Oxide-Sensing Regulatory Proteins Containing [4Fe-4S] Clusters Gives Rise to Multiple Iron-Nitrosyl Complexes.
abstract: The reaction of protein-bound iron-sulfur (Fe-S) clusters with nitric oxide (NO) plays key roles in NO-mediated toxicity and signaling. Elucidation of the mechanism of the reaction of NO with DNA regulatory proteins that contain Fe-S clusters has been hampered by a lack of information about the nature of the iron-nitrosyl products formed. Herein, we report nuclear resonance vibrational spectroscopy (NRVS) and density functional theory (DFT) calculations that identify NO reaction products in WhiD and NsrR, regulatory proteins that use a [4Fe-4S] cluster to sense NO. This work reveals that nitrosylation yields multiple products structurally related to Roussin's Red Ester (RRE, [Fe2(NO)4(Cys)2]) and Roussin's Black Salt (RBS, [Fe4(NO)7S3]. In the latter case, the absence of32S/34S shifts in the Fe-S region of the NRVS spectra suggest that a new species, Roussin's Black Ester (RBE), may be formed, in which one or more of the sulfide ligands is replaced by Cys thiolates.
authors: Department of Chemistry, University of California, Davis, CA, 95616, USA.
authors: Pauline N
authors: PN
authors: Serrano
authors: Department of Chemistry, University of California, Davis, CA, 95616, USA.|Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
authors: Hongxin
authors: H
authors: Wang
authors: Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
authors: Jason C
authors: JC
authors: Crack
authors: Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
authors: Christopher
authors: C
authors: Prior
authors: School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, UK.
authors: Matthew I
authors: MI
authors: Hutchings
authors: Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
authors: Andrew J
authors: AJ
authors: Thomson
authors: University of Tennessee Space Institute, Tullahome, TN, 37388-9700, USA.
authors: Saeed
authors: S
authors: Kamali
authors: Research and Utilization Division, SPring-8/JASRI, 1-1-1 Kouto, Sayo, Hyogo, 679-5198, Japan.
authors: Yoshitaka
authors: Y
authors: Yoda
authors: Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA.
authors: Jiyong
authors: J
authors: Zhao
authors: Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA.
authors: Michael Y
authors: MY
authors: Hu
authors: Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA.
authors: Ercan E
authors: EE
authors: Alp
authors: Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
authors: Vasily S
authors: VS
authors: Oganesyan
authors: Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
authors: Nick E
authors: NE
authors: Le Brun
authors: Department of Chemistry, University of California, Davis, CA, 95616, USA.|Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
authors: Stephen P
authors: SP
authors: Cramer
mesh_terms: D007501:Iron / Q000737:chemistry / Q000378:metabolism*; D007506:Iron-Sulfur Proteins / Q000737:chemistry / Q000378:metabolism*; D008968:Molecular Conformation; D009569:Nitric Oxide / Q000737:chemistry / Q000378:metabolism*; D009589:Nitrogen Oxides / Q000737:chemistry / Q000378:metabolism*; D009603:Nitroso Compounds / Q000378:metabolism*; D011789:Quantum Theory
chemical_list: D007506:Iron-Sulfur Proteins; D009589:Nitrogen Oxides; D009603:Nitroso Compounds; D009569:Nitric Oxide; C073661:dinitrosyl iron complex; D007501:Iron
keywords: gene regulation; iron-sulfur clusters; nitric oxide; nuclear vibrational resonance spectroscopy; synchrotron radiation