title: The interaction of human neuroglobin with hydrogen sulphide.
abstract: Neuroglobin has been identified to protect brain neurons from apoptotic stress. Hydrogen sulphide has a role in the brain as a neuromodulator, involving NMDA receptor activation. Here we report on studies of the in vitro interaction of ferric neuroglobin with hydrogen sulphide. Hydrogen sulphide binds very tightly to the heme group of neuroglobin in a biphasic reaction. The faster of the two reaction processes is concentration dependent whilst the slower process is not. The rate of hydrogen sulphide binding is pH sensitive and as the pH is reduced over the physiological range the rate of reaction increases by a factor of approximately 10. This change in reactivity appears to reflect the ionisation of the heme distal His ligand rather than a preference for the binding of H(2)S. We discuss the potential role of neuroglobin in the modulation of hydrogen sulphide sensitivity of neurons in the brain.
authors: School of Biological Sciences, University of Auckland, Auckland, New Zealand. T.Brittain@auckland.ac.nz
authors: Thomas
authors: T
authors: Brittain
authors: Yuliana
authors: Y
authors: Yosaatmadja
authors: Kristen
authors: K
authors: Henty
mesh_terms: D005914:Globins / Q000378:metabolism*; D006418:Heme / Q000737:chemistry; D006801:Humans; D006862:Hydrogen Sulfide / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D000078787:Neuroglobin
chemical_list: D009419:Nerve Tissue Proteins; D000078787:Neuroglobin; D006418:Heme; D005914:Globins; D006862:Hydrogen Sulfide