Kinetics of ferric Mycobacterium leprae truncated hemoglobin O (trHbO-Fe(III)) oxidation by H2O2 and of trHbO-Fe(IV)=O reduction by (NO)-N-center dot and NO2- are reported. The value of the second-order rate constant for H2O2-mediated oxidation of trHbO-Fe(III) is 2.4 x 10(3) M-1 s(-1). The value of the second-order rate constant for (NO)-N-center dot-mediated reduction of trHbO-Fe(IV)=O is 7.8 x 10(6) M-1 s(-1). The value of the first-order rate constant for trHbO-Fe(III)-ONO decay to the resting form trHbO-Fe(III) is 2.1 x 10(6) s(-1). The value of the second-order rate constant for NO2--mediated reduction of trHbO-Fe(IV)=O is 3.1 x 10(3) M-1 s(-1). As a whole, trHbO-Fe(IV)=O, generated upon reaction with H2O2, catalyzes (NO)-N-center dot reduction to NO2-. In turn, (NO)-N-center dot and NO2- act as antioxidants of trHbO-Fe(IV)=O, which could be responsible for the oxidative damage of the mycobacterium. Therefore, Mycobacterium leprae trHbO could be involved in both H2O2 and (NO)-N-center dot scavenging, protecting from nitrosative and oxidative stress, and sustaining mycobacterial respiration. (C) 2008 Elsevier Inc. All rights reserved.

Ascenzi, P., De Marinis, E., Coletta, M., Visca, P. (2008). H2O2 and {radical dot}NO scavenging by Mycobacterium leprae truncated hemoglobin O. BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 373(2), 197-201 [10.1016/j.bbrc.2008.05.168].

H2O2 and {radical dot}NO scavenging by Mycobacterium leprae truncated hemoglobin O

COLETTA, MASSIMILIANO;
2008-01-01

Abstract

Kinetics of ferric Mycobacterium leprae truncated hemoglobin O (trHbO-Fe(III)) oxidation by H2O2 and of trHbO-Fe(IV)=O reduction by (NO)-N-center dot and NO2- are reported. The value of the second-order rate constant for H2O2-mediated oxidation of trHbO-Fe(III) is 2.4 x 10(3) M-1 s(-1). The value of the second-order rate constant for (NO)-N-center dot-mediated reduction of trHbO-Fe(IV)=O is 7.8 x 10(6) M-1 s(-1). The value of the first-order rate constant for trHbO-Fe(III)-ONO decay to the resting form trHbO-Fe(III) is 2.1 x 10(6) s(-1). The value of the second-order rate constant for NO2--mediated reduction of trHbO-Fe(IV)=O is 3.1 x 10(3) M-1 s(-1). As a whole, trHbO-Fe(IV)=O, generated upon reaction with H2O2, catalyzes (NO)-N-center dot reduction to NO2-. In turn, (NO)-N-center dot and NO2- act as antioxidants of trHbO-Fe(IV)=O, which could be responsible for the oxidative damage of the mycobacterium. Therefore, Mycobacterium leprae trHbO could be involved in both H2O2 and (NO)-N-center dot scavenging, protecting from nitrosative and oxidative stress, and sustaining mycobacterial respiration. (C) 2008 Elsevier Inc. All rights reserved.
2008
Pubblicato
Rilevanza internazionale
Articolo
Sì, ma tipo non specificato
Settore BIO/10 - BIOCHIMICA
English
H2O2 and {radical dot}NO scavenging; Kinetics; Mycobacterium leprae truncated hemoglobin O; Nitrosative and oxidative stress
Ascenzi, P., De Marinis, E., Coletta, M., Visca, P. (2008). H2O2 and {radical dot}NO scavenging by Mycobacterium leprae truncated hemoglobin O. BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 373(2), 197-201 [10.1016/j.bbrc.2008.05.168].
Ascenzi, P; De Marinis, E; Coletta, M; Visca, P
Articolo su rivista
File in questo prodotto:
File Dimensione Formato  
BBRC 2008 H2O2 NO scavenging lebra.pdf

accesso aperto

Dimensione 311.66 kB
Formato Adobe PDF
311.66 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/41190
Citazioni
  • ???jsp.display-item.citation.pmc??? 3
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 21
social impact