Oxidative titration of monomolecular films of cytochrome c-II and of bacteriochlorophyll

Biochemistry ◽  
1972 ◽  
Vol 11 (1) ◽  
pp. 92-96 ◽  
Author(s):  
P. Reinach ◽  
S. S. Brody
Keyword(s):  
Cytochrome C ◽  
Monomolecular Films

Photosynthetic Electron Carriers at a Heptane-Water Interface

1976 ◽  
Vol 31 (9-10) ◽  
pp. 569-574 ◽  
Author(s):  
S. S. Brody ◽  
N. F. Owens
Keyword(s):  
Cytochrome C ◽  
Surface Properties ◽  
Strong Interaction ◽  
The Other ◽  
Water Interface ◽  
Air Water Interface ◽  
Monomolecular Films ◽  
Mixed Films ◽  
Electron Carriers

Abstract Surface properties of monomolecular films of chlorophyll (Chi), plastocyanin (Pc), cytochrome c (Cyt) and ferridoxin (Fd) were measured at a heptane-water interface. Mixed films of Chl and the other components were examined in darkness and in light. The area/molecule, A, for Fd (from Cl. pasteurianum) is much larger at a heptane-water than Fd (from spinach) at an air-water interface. This difference in A may be the source of the Fd or the extent of denaturation at the different interfaces. There appears to be a photoreaction between Chil and Fd in the presence of ascorbate. The A for Cyt is much larger at a heptane-water than at an air-water interface. In mixed films there is a strong interaction between Chl and reduced Cyt in the dark. No such interaction is ob­served between Chi and oxidized Cyt. With mixed films of Chi and reduced Pc there is a significant, reversible, light induced change in ΔV.

Nucleic Acid Molecules Prepared by Monolayer Techniques

1972 ◽  
Vol 30 ◽  
pp. 178-179
Author(s):  
Dimitrij Lang
Keyword(s):  
Electron Microscopy ◽  
Standard Deviation ◽  
Nucleic Acid ◽  
Cytochrome C ◽  
Nucleic Acids ◽  
Contour Length ◽  
Sample Standard Deviation ◽  
Molecular Weights ◽  
Length Measurements ◽  
Protein Monolayer

The success of the protein monolayer technique for electron microscopy of individual DNA molecules is based on the prevention of aggregation and orientation of the molecules during drying on specimen grids. DNA adsorbs first to a surface-denatured, insoluble cytochrome c monolayer which is then transferred to grids, without major distortion, by touching. Fig. 1 shows three basic procedures which, modified or not, permit the study of various important properties of nucleic acids, either in concert with other methods or exclusively:1) Molecular weights relative to DNA standards as well as number distributions of molecular weights can be obtained from contour length measurements with a sample standard deviation between 1 and 4%.

Activation of cytochrome c to a peroxidase compound I-type intermediate by H2O2: relevance to redox signalling in apoptosis

2004 ◽  
Vol 71 ◽  
pp. 97-106 ◽  
Author(s):  
Mark Burkitt ◽  
Clare Jones ◽  
Andrew Lawrence ◽  
Peter Wardman
Keyword(s):  
Cytochrome C ◽  
Hydroxyl Radical ◽  
Redox Regulation ◽  
Chemotherapeutic Agents ◽  
Tyrosyl Radical ◽  
Compound I ◽  
Definitive Evidence ◽  
Enhanced Production ◽  
Physico Chemical

The release of cytochrome c from mitochondria during apoptosis results in the enhanced production of superoxide radicals, which are converted to H2O2 by Mn-superoxide dismutase. We have been concerned with the role of cytochrome c/H2O2 in the induction of oxidative stress during apoptosis. Our initial studies showed that cytochrome c is a potent catalyst of 2′,7′-dichlorofluorescin oxidation, thereby explaining the increased rate of production of the fluorophore 2′,7′-dichlorofluorescein in apoptotic cells. Although it has been speculated that the oxidizing species may be a ferryl-haem intermediate, no definitive evidence for the formation of such a species has been reported. Alternatively, it is possible that the hydroxyl radical may be generated, as seen in the reaction of certain iron chelates with H2O2. By examining the effects of radical scavengers on 2′,7′-dichlorofluorescin oxidation by cytochrome c/H2O2, together with complementary EPR studies, we have demonstrated that the hydroxyl radical is not generated. Our findings point, instead, to the formation of a peroxidase compound I species, with one oxidizing equivalent present as an oxo-ferryl haem intermediate and the other as the tyrosyl radical identified by Barr and colleagues [Barr, Gunther, Deterding, Tomer and Mason (1996) J. Biol. Chem. 271, 15498-15503]. Studies with spin traps indicated that the oxo-ferryl haem is the active oxidant. These findings provide a physico-chemical basis for the redox changes that occur during apoptosis. Excessive changes (possibly catalysed by cytochrome c) may have implications for the redox regulation of cell death, including the sensitivity of tumour cells to chemotherapeutic agents.

Solution structure of cytochrome b5 mutant (E44/48/56A/D60A) and its interaction with cytochrome c

2001 ◽  
Vol 268 (6) ◽  
pp. 1620-1630
Author(s):  
Yibing Wu ◽  
Yunhua Wang ◽  
Chengmin Qian ◽  
Jun Lu ◽  
Ercheng Li ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Solution Structure ◽  
Cytochrome B5

Expression of sunflower cytochrome c mRNA is tissue-specific and controlled by nitrate and light

1997 ◽  
Vol 99 (2) ◽  
pp. 342-347 ◽  
Author(s):  
Silvina A. Felitti ◽  
Raquel L. Chan ◽  
Gabriela Gago ◽  
Estela M. Valle ◽  
Daniel H. Gonzalez
Keyword(s):  
Cytochrome C ◽  
Tissue Specific

Viscoelastic relaxation of insoluble monomolecular films

1988 ◽  
Vol 49 (7) ◽  
pp. 1271-1293 ◽  
Author(s):  
J.C. Earnshaw ◽  
R.C. McGivern ◽  
P.J. Winch
Keyword(s):  
Viscoelastic Relaxation ◽  
Monomolecular Films

A STUDY OF CYTOCHROME c AND CYTOCHROME b2 CORE IN THE OXIDIZED AND REDUCED STATES USING EXAFS AND XANES SPECTROSCOPIES

1986 ◽  
Vol 47 (C8) ◽  
pp. C8-1143-C8-1146
Author(s):  
I. ASCONE ◽  
J. GOULON ◽  
A. BIANCONI ◽  
M. TEGONI ◽  
F. LABEYRIE
Keyword(s):  
Cytochrome C
Sign in / Sign up

Export Citation Format

Share Document