Characterization of the haemoglobin-mediated inhibition of the enzymatic activity of bovine serum amine oxidase

P. Pietrangeli, L. Marcocci, L. Morpurgo, O. Befani, X. Wang, B. Mondovi

Research output: Contribution to journalArticle

Abstract

Haemoglobin has been previously identified as responsible for the decreased enzymatic activity of copper bovine serum amine oxidase (BSAO) in suspensions of human or bovine hemolyzed erythrocytes [Marcocci, L., Pietrangeli, P., Befani, O., Mavelli I., & Mondovi', B. (1991b) Life Chem. Report, 9, 171-177]. This is confirmed by present results on bovine methaemoglobin. Bovine globin and horse skeletal muscle mioglobin showed a similar inhibiting ability, but neither bovine serum albumin nor cytochrome c inhibited BSAO activity under the same experimental conditions. The inhibitory effect of bovine haemoglobin was dependent on pH only at high buffer ionic strength. It was highest in physiological conditions (PBS) where haemoglobin acted as a reversible non competitive inhibitor of BSAO activity, with apparent Ki of 0.5 mM at 37°C. The inhibition was unaffected by partial BSAO deglycosylation (40% of glucidic residues removed) but decreased when haemoglobin lysine groups were derivatised using citraconic anhydride. A possible molecular mechanism underlying the inhibitory effect is discussed.

Original languageEnglish (US)
Pages (from-to)7-12
Number of pages6
JournalItalian Journal of Biochemistry
Volume47
Issue number1
Publication statusPublished - Mar 1 1998

    Fingerprint

ASJC Scopus subject areas

  • Biochemistry

Cite this

Pietrangeli, P., Marcocci, L., Morpurgo, L., Befani, O., Wang, X., & Mondovi, B. (1998). Characterization of the haemoglobin-mediated inhibition of the enzymatic activity of bovine serum amine oxidase. Italian Journal of Biochemistry, 47(1), 7-12.