title: Engineering the internal cavity of neuroglobin demonstrates the role of the haem-sliding mechanism.
abstract: Neuroglobin is a member of the globin family involved in neuroprotection; it is primarily expressed in the brain and retina of vertebrates. Neuroglobin belongs to the heterogeneous group of hexacoordinate globins that have evolved in animals, plants and bacteria, endowed with the capability of reversible intramolecular coordination, allowing the binding of small gaseous ligands (O2, NO and CO). In a unique fashion among haemoproteins, ligand-binding events in neuroglobin are dependent on the sliding of the haem itself within a preformed internal cavity, as revealed by the crystal structure of its CO-bound derivative. Point mutants of the neuroglobin internal cavity have been engineered and their functional and structural characterization shows that hindering the haem displacement leads to a decrease in CO affinity, whereas reducing the cavity volume without interfering with haem sliding has negligible functional effects.
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche `A. Rossi Fanelli', Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Avella
authors.affiliation: Departments of Physiology and Cellular Biophysics, Columbia University College of Physicians and Surgeons, Russ Berrie Pavilion, 1150 St Nicholas Avenue, New York, NY 10032, USA.
authors.forename: C
authors.initials: C
authors.lastname: Ardiccioni
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche `A. Rossi Fanelli', Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Scaglione
authors.affiliation: Biochemistry Department, Cambridge University, Sanger Building, 80 Tennis Court Road, Cambridge CB2 1GA, England.
authors.forename: T
authors.initials: T
authors.lastname: Moschetti
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche `A. Rossi Fanelli', Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Rondinelli
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche `A. Rossi Fanelli', Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy.
authors.forename: L C
authors.initials: LC
authors.lastname: Montemiglio
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche `A. Rossi Fanelli', Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Savino
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche `A. Rossi Fanelli', Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Giuffrè
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche `A. Rossi Fanelli', Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Brunori
authors.affiliation: Istituto Pasteur-Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche `A. Rossi Fanelli', Sapienza Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Vallone
mesh_terms: D002248:Carbon Monoxide / Q000737:chemistry; D018360:Crystallography, X-Ray; D005914:Globins / Q000737:chemistry* / Q000235:genetics; D006418:Heme / Q000737:chemistry*; D007700:Kinetics; D008958:Models, Molecular; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000737:chemistry* / Q000235:genetics; D000078787:Neuroglobin; D015202:Protein Engineering
chemical_list: D009419:Nerve Tissue Proteins; D000078787:Neuroglobin; D006418:Heme; D002248:Carbon Monoxide; D005914:Globins
keywords: haem sliding; neuroglobin; protein engineering