Characterisation of S‐nitrosohaemoglobin by mass spectrometry

FEBS Letters

Ferranti, Pasquale⁴  Marino, Gennaro¹  Mamone, Gianfranco⁴  Malorni, Antonio²  Sannolo, Nicola³ 

[1] Dipartimento di Chimica Organica e Biologica dell' Università di Napoli Federico II, Napoli, Italy;Istituto per la Chimica di Molecole di Interesse Biologico del CNR, Arco Felice, Italy;Sezione di Medicina Occupazionale, Dipartimento di Biochimica e Biofisica, Seconda Università di Napoli, Napoli, Italy;International Mass Spectrometry Facilities Centre of CNR, Via P. Castellino 111, 80131 Napoli, Italy

关键词: Haemoglobin;    Nitric oxide;    S-nitrosothiol;    S-nitrosocysteine;    S-nitrosohaemoglobin;    Mass spectrometry;   

DOI  :  10.1016/S0014-5793(96)01258-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Recent studies have demonstrated the biological importance of the interaction of S-nitrosothiols, which can be considered as nitric oxide (NO) protein donors, especially haemoglobin, at the level of Cys residues. It was recently proposed that S-nitrosohaemoglobin is formed within red blood cells and serves as a regulatory function. In human haemoglobin the α-subunit contains one Cys residue and the β-subunit contains two Cys residues, one of which (β-Cys⁹³) is highly reactive and conserved among species, although its function has remained unknown. Electrospray ionization mass spectrometry was used to monitor the results of exposure of haemolysates to S-nitrosocysteine under different conditions and thus addressed some aspects of NO–haemoglobin interaction. When an equimolar ratio of S-nitrosothiol was added to haemoglobin, only a single NO molecule was added. Peptide mapping by liquid chromatography–mass spectrometry located the nitrosyl group at the level of β-Cys⁹³ demonstrating that this was the preferred site of formation of S-nitrosohaemoglobin. The present data also suggest that electrospray mass spectrometry can allow quantification and characterisation of S-nitrosoproteins in blood.

【 授权许可】

Unknown