Abstract
Nitric oxide binding to ferrous native horse heart cytochrome c and to its carboxymethylated derivative has been investigated quantitatively by EPR and absorbance spectroscopy. The X-band EPR spectra and the absorption spectra in the Soret region of the nitrosylated derivative of ferrous native and carboxymethylated cytochrome c display the same basic characteristics reported for the beef heart cytochrome a3 in cytochrome c oxidase, and horseradish and baker's yeast cytochrome c peroxidase, as well as the high affinity form of oxygen carrying proteins. Values of the dissociation equilibrium constant for nitrosylation of ferrous native and carboxymethylated cytochrome c are 8.2 × 10-6 M and ≤ 5 × 10-8 M, respectively, at pH 7.0 and 10°C. The results here reported represent clearcut evidence for the nitric oxide-induced cleavage of the FeMet80 bond in ferrous native cytochrome c, and allow estimation of the free energy associated to the heme-iron sixth coordination bond ( > 10 kJ mol-1, at 10°C).
| Original language | English |
|---|---|
| Pages (from-to) | 273-280 |
| Number of pages | 8 |
| Journal | Journal of Inorganic Biochemistry |
| Volume | 53 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - 1994 |
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ASJC Scopus subject areas
- Biochemistry
- Inorganic Chemistry
Cite this
Nitric oxide binding to ferrous native horse heart cytochrome c and to its carboxymethylated derivative : A spectroscopic and thermodynamic Study. / Ascenzi, Paolo; Coletta, Massimo; Santucci, Roberto; Polizio, Francesca; Desideri, Alessandro.
In: Journal of Inorganic Biochemistry, Vol. 53, No. 4, 1994, p. 273-280.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Nitric oxide binding to ferrous native horse heart cytochrome c and to its carboxymethylated derivative
T2 - A spectroscopic and thermodynamic Study
AU - Ascenzi, Paolo
AU - Coletta, Massimo
AU - Santucci, Roberto
AU - Polizio, Francesca
AU - Desideri, Alessandro
PY - 1994
Y1 - 1994
N2 - Nitric oxide binding to ferrous native horse heart cytochrome c and to its carboxymethylated derivative has been investigated quantitatively by EPR and absorbance spectroscopy. The X-band EPR spectra and the absorption spectra in the Soret region of the nitrosylated derivative of ferrous native and carboxymethylated cytochrome c display the same basic characteristics reported for the beef heart cytochrome a3 in cytochrome c oxidase, and horseradish and baker's yeast cytochrome c peroxidase, as well as the high affinity form of oxygen carrying proteins. Values of the dissociation equilibrium constant for nitrosylation of ferrous native and carboxymethylated cytochrome c are 8.2 × 10-6 M and ≤ 5 × 10-8 M, respectively, at pH 7.0 and 10°C. The results here reported represent clearcut evidence for the nitric oxide-induced cleavage of the FeMet80 bond in ferrous native cytochrome c, and allow estimation of the free energy associated to the heme-iron sixth coordination bond ( > 10 kJ mol-1, at 10°C).
AB - Nitric oxide binding to ferrous native horse heart cytochrome c and to its carboxymethylated derivative has been investigated quantitatively by EPR and absorbance spectroscopy. The X-band EPR spectra and the absorption spectra in the Soret region of the nitrosylated derivative of ferrous native and carboxymethylated cytochrome c display the same basic characteristics reported for the beef heart cytochrome a3 in cytochrome c oxidase, and horseradish and baker's yeast cytochrome c peroxidase, as well as the high affinity form of oxygen carrying proteins. Values of the dissociation equilibrium constant for nitrosylation of ferrous native and carboxymethylated cytochrome c are 8.2 × 10-6 M and ≤ 5 × 10-8 M, respectively, at pH 7.0 and 10°C. The results here reported represent clearcut evidence for the nitric oxide-induced cleavage of the FeMet80 bond in ferrous native cytochrome c, and allow estimation of the free energy associated to the heme-iron sixth coordination bond ( > 10 kJ mol-1, at 10°C).
UR - http://www.scopus.com/inward/record.url?scp=0028340452&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028340452&partnerID=8YFLogxK
U2 - 10.1016/0162-0134(94)85114-X
DO - 10.1016/0162-0134(94)85114-X
M3 - Article
VL - 53
SP - 273
EP - 280
JO - Journal of Inorganic Biochemistry
JF - Journal of Inorganic Biochemistry
SN - 0162-0134
IS - 4
ER -