title: Near-complete backbone resonance assignments of acid-denatured human cytochrome c in dimethylsulfoxide: a prelude to studying interactions with phospholipids.
abstract: Human cytochrome c plays a central role in the mitochondrial electron transfer chain and in the intrinsic apoptosis pathway. Through the interaction with the phospholipid cardiolipin, cytochrome c triggers release of pro-apoptotic factors, including itself, from the mitochondrion into the cytosol of cells undergoing apoptosis. The cytochrome c/cardiolipin complex has been extensively studied through various spectroscopies, most recently with high-field solution and solid-state NMR spectroscopies, but there is no agreement between the various studies on key structural features of cytochrome c in its complex with cardiolipin. In the present study, we report backbone1H,13C,15N resonance assignments of acid-denatured human cytochrome c in the aprotic solvent dimethylsulfoxide. These have led to the assignment of a reference 2D1H-15N HSQC spectrum in which out of the 99 non-proline residues 87% of the backbone amides are assigned. These assignments are being used in an interrupted H/D exchange strategy to map the binding site of cardiolipin on human cytochrome c.
authors.affiliation: School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK.
authors.forename: Andreas Ioannis
authors.initials: AI
authors.lastname: Karsisiotis
authors.affiliation: School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK.
authors.forename: Oliver M
authors.initials: OM
authors.lastname: Deacon
authors.affiliation: School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
authors.forename: Colin
authors.initials: C
authors.lastname: Macdonald
authors.affiliation: School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
authors.forename: Tharin M A
authors.initials: TMA
authors.lastname: Blumenschein
authors.affiliation: School of Chemistry, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
authors.forename: Geoffrey R
authors.initials: GR
authors.lastname: Moore
authors.affiliation: School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK. jworrall@essex.ac.uk.
authors.forename: Jonathan A R
authors.identifier: http://orcid.org/0000-0002-1863-834X
authors.initials: JAR
authors.lastname: Worrall
mesh_terms: D045304:Cytochromes c / Q000737:chemistry* / Q000378:metabolism*; D004121:Dimethyl Sulfoxide / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019906:Nuclear Magnetic Resonance, Biomolecular; D010743:Phospholipids / Q000378:metabolism*; D011485:Protein Binding; D011489:Protein Denaturation
chemical_list: D010743:Phospholipids; D045304:Cytochromes c; D004121:Dimethyl Sulfoxide
keywords: Acid-denatured; Apoptosis; Cardiolipin; DMSO; Human cytochrome c