Abstract
Upon cardiolipin (CL) liposomes binding, horse heart cytochrome c (cytc) changes its tertiary structure disrupting the heme-Fe-Met80 distal bond, reduces drastically the midpoint potential, binds CO and NO with high affinity, displays peroxidase activity, and facilitates peroxynitrite isomerization. Here, the effect of CL liposomes on the nitrite reductase activity of ferrous cytc (cytc-Fe(II)) is reported. In the absence of CL liposomes, hexa-coordinated cytc-Fe(II) displays a very low value of the apparent second-order rate constant for the NO2 --mediated conversion of cytc-Fe(II) to cytc-Fe(II)-NO (k on = (7.3 ± 0.7) × 10-2 M-1 s-1; at pH 7.4 and 20.0 °C). However, CL liposomes facilitate the NO2 --mediated nitrosylation of cytc-Fe(II) in a dose-dependent manner inducing the penta-coordination of the heme-Fe(II) atom. The value of k on for the NO2 --mediated conversion of CL-cytc-Fe(II) to CL-cytc-Fe(II)-NO is 2.6 ± 0.3 M-1 s-1 (at pH 7.4 and 20.0°C). Values of the apparent dissociation equilibrium constant for CL liposomes binding to cytc-Fe(II) are (2.2 ± 0.2) × 10-6 M, (1.8 ± 0.2) × 10-6 M, and (1.4 ± 0.2) × 10-6 M at pH 6.5, 7.4, and 8.1, respectively, and 20.0°C. These results suggest that the NO2 --mediated conversion of CL-cytc-Fe(II) to CL-cytc-Fe(II)-NO could play anti-apoptotic effects impairing lipid peroxidation and therefore the initiation of the cell death program by the release of pro-apoptotic factors (including cytc) in the cytoplasm.
| Original language | English |
|---|---|
| Pages (from-to) | 1195-1201 |
| Number of pages | 7 |
| Journal | Journal of Biological Inorganic Chemistry |
| Volume | 19 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - Jun 27 2014 |
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Keywords
- Allostery
- Cardiolipin
- Horse heart cytochrome c
- Nitrite reductase activity
- Nitrite-mediated nitrosylation
ASJC Scopus subject areas
- Biochemistry
- Inorganic Chemistry
- Medicine(all)
Cite this
Cardiolipin modulates allosterically the nitrite reductase activity of horse heart cytochrome c. / Ascenzi, Paolo; Marino, Maria; Polticelli, Fabio; Santucci, Roberto; Coletta, Massimo.
In: Journal of Biological Inorganic Chemistry, Vol. 19, No. 7, 27.06.2014, p. 1195-1201.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Cardiolipin modulates allosterically the nitrite reductase activity of horse heart cytochrome c
AU - Ascenzi, Paolo
AU - Marino, Maria
AU - Polticelli, Fabio
AU - Santucci, Roberto
AU - Coletta, Massimo
PY - 2014/6/27
Y1 - 2014/6/27
N2 - Upon cardiolipin (CL) liposomes binding, horse heart cytochrome c (cytc) changes its tertiary structure disrupting the heme-Fe-Met80 distal bond, reduces drastically the midpoint potential, binds CO and NO with high affinity, displays peroxidase activity, and facilitates peroxynitrite isomerization. Here, the effect of CL liposomes on the nitrite reductase activity of ferrous cytc (cytc-Fe(II)) is reported. In the absence of CL liposomes, hexa-coordinated cytc-Fe(II) displays a very low value of the apparent second-order rate constant for the NO2 --mediated conversion of cytc-Fe(II) to cytc-Fe(II)-NO (k on = (7.3 ± 0.7) × 10-2 M-1 s-1; at pH 7.4 and 20.0 °C). However, CL liposomes facilitate the NO2 --mediated nitrosylation of cytc-Fe(II) in a dose-dependent manner inducing the penta-coordination of the heme-Fe(II) atom. The value of k on for the NO2 --mediated conversion of CL-cytc-Fe(II) to CL-cytc-Fe(II)-NO is 2.6 ± 0.3 M-1 s-1 (at pH 7.4 and 20.0°C). Values of the apparent dissociation equilibrium constant for CL liposomes binding to cytc-Fe(II) are (2.2 ± 0.2) × 10-6 M, (1.8 ± 0.2) × 10-6 M, and (1.4 ± 0.2) × 10-6 M at pH 6.5, 7.4, and 8.1, respectively, and 20.0°C. These results suggest that the NO2 --mediated conversion of CL-cytc-Fe(II) to CL-cytc-Fe(II)-NO could play anti-apoptotic effects impairing lipid peroxidation and therefore the initiation of the cell death program by the release of pro-apoptotic factors (including cytc) in the cytoplasm.
AB - Upon cardiolipin (CL) liposomes binding, horse heart cytochrome c (cytc) changes its tertiary structure disrupting the heme-Fe-Met80 distal bond, reduces drastically the midpoint potential, binds CO and NO with high affinity, displays peroxidase activity, and facilitates peroxynitrite isomerization. Here, the effect of CL liposomes on the nitrite reductase activity of ferrous cytc (cytc-Fe(II)) is reported. In the absence of CL liposomes, hexa-coordinated cytc-Fe(II) displays a very low value of the apparent second-order rate constant for the NO2 --mediated conversion of cytc-Fe(II) to cytc-Fe(II)-NO (k on = (7.3 ± 0.7) × 10-2 M-1 s-1; at pH 7.4 and 20.0 °C). However, CL liposomes facilitate the NO2 --mediated nitrosylation of cytc-Fe(II) in a dose-dependent manner inducing the penta-coordination of the heme-Fe(II) atom. The value of k on for the NO2 --mediated conversion of CL-cytc-Fe(II) to CL-cytc-Fe(II)-NO is 2.6 ± 0.3 M-1 s-1 (at pH 7.4 and 20.0°C). Values of the apparent dissociation equilibrium constant for CL liposomes binding to cytc-Fe(II) are (2.2 ± 0.2) × 10-6 M, (1.8 ± 0.2) × 10-6 M, and (1.4 ± 0.2) × 10-6 M at pH 6.5, 7.4, and 8.1, respectively, and 20.0°C. These results suggest that the NO2 --mediated conversion of CL-cytc-Fe(II) to CL-cytc-Fe(II)-NO could play anti-apoptotic effects impairing lipid peroxidation and therefore the initiation of the cell death program by the release of pro-apoptotic factors (including cytc) in the cytoplasm.
KW - Allostery
KW - Cardiolipin
KW - Horse heart cytochrome c
KW - Nitrite reductase activity
KW - Nitrite-mediated nitrosylation
UR - http://www.scopus.com/inward/record.url?scp=84921027484&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84921027484&partnerID=8YFLogxK
U2 - 10.1007/s00775-014-1175-9
DO - 10.1007/s00775-014-1175-9
M3 - Article
C2 - 24969400
AN - SCOPUS:84921027484
VL - 19
SP - 1195
EP - 1201
JO - Journal of Biological Inorganic Chemistry
JF - Journal of Biological Inorganic Chemistry
SN - 0949-8257
IS - 7
ER -