Influence of electrochemical properties in determining the sensitivity of [4Fe-4S] clusters in proteins to oxidative damage

2001 ◽  
Vol 360 (3) ◽  
pp. 717-726 ◽  
Author(s):  
Gareth J. TILLEY ◽  
Raul CAMBA ◽  
Barbara K. BURGESS ◽  
Fraser A. ARMSTRONG
Keyword(s):  
Oxidative Damage ◽  
Structural Changes ◽  
Reduction Potential ◽  
Azotobacter Vinelandii ◽  
Pyrococcus Furiosus ◽  
Protein Film ◽  
Protein Film Voltammetry ◽  
Thauera Aromatica ◽  
Key Factor ◽  
Ferredoxin I

Interconversion between [4Fe-4S] cubane and [3Fe-4S] cuboidal states represents one of the simplest structural changes an iron–sulphur cluster can undertake. This reaction is implicated in oxidative damage and in modulation of the activity and regulation of certain enzymes, and it is therefore important to understand the factors governing cluster stability and the processes that activate cluster conversion. In the present study, protein film voltammetry has been used to induce and monitor the oxidative conversion of [4Fe-4S] into [3Fe-4S] clusters in different variants of Azotobacter vinelandii ferredoxin I (AvFdI; the 8Fe form of the native protein), and ΔThr14/ΔAsp15, Thr14 → Cys (T14C) and C42D mutants. The electrochemical results have been correlated with the differing oxygen sensitivities of [4Fe-4S] clusters, and comparisons have been drawn with other ferredoxins (Desulfovibrio africanus FdIII, Clostridium pasteurianum Fd, Thauera aromatica Fd and Pyrococcus furiosus Fd). In contrast with high-potential iron–sulphur proteins (HiPIPs) for which the oxidized species [4Fe-4S]3+ is inert to degradation and can be isolated, the hypervalent state in these ferredoxins (most obviously the 3+ level) is very labile, and the reduction potential at which this is formed is a key factor in determining the cluster's resistance to oxidative damage.

scholarly journals Azotobacter vinelandii ferredoxin I. Alteration of individual surface charges and the [4FE-4S]2+/+ cluster reduction potential.

1994 ◽  
Vol 269 (11) ◽  
pp. 8564-8575
Author(s):  
B. Shen ◽  
D.R. Jollie ◽  
C.D. Stout ◽  
T.C. Diller ◽  
F.A. Armstrong ◽  
...  
Keyword(s):  
Reduction Potential ◽  
Azotobacter Vinelandii ◽  
Surface Charges ◽  
Ferredoxin I ◽  
Cluster Reduction

scholarly journals Voltammetric studies of the reactions of iron–sulphur clusters ([3Fe-4S] or [M3Fe-4S]) formed in Pyrococcus furiosus ferredoxin

1998 ◽  
Vol 335 (2) ◽  
pp. 357-368 ◽  
Author(s):  
Sarah E. J. FAWCETT ◽  
David DAVIS ◽  
Jacques L. BRETON ◽  
Andrew J. THOMSON ◽  
Fraser A. ARMSTRONG
Keyword(s):  
Pyrococcus Furiosus ◽  
Ph Dependence ◽  
Distinct Species ◽  
Bulk Solution ◽  
Protein Film ◽  
Protein Film Voltammetry ◽  
Significant Difference ◽  
The Status ◽  
Wide Ph Range ◽  
Ph Range

Reactions of the [3Fe-4S] cluster and various metallated [M3Fe-4S] adducts co-ordinated in the ferredoxin from the hyperthermophile Pyrococcus furiosus have been studied by protein-film voltammetry, bulk-solution voltammetry, solution kinetics and magnetic CD (MCD). The [3Fe-4S] cluster exhibits two couples, [3Fe-4S]+/0 and [3Fe-4S]0/2-. Film voltammetry is possible over a wide pH range (2–8), revealing that the [3Fe-4S]+/0 couple shows a complex pH dependence with pKred1 = 2.8, pKox = 4.9 and pKred2 = 6.7. From MCD, pKred1 corresponds with protonation of [3Fe-4S]0 to give a spectroscopically distinct species, as reported for ferredoxins from Azotobacterand Sulfolobus. The status of the disulphide/disulphydryl entity makes no significant difference to the data (given for the -S-S- form). Formation of the hyper-reduced [3Fe-4S]2- state is observed, requiring 3H+ for the overall 3e- reduction of [3Fe-4S]+, the change therefore being electroneutral. By comparison with the ferredoxin from Desulfovibrio africanus, uptake of Fe(II) and other M(II) by [3Fe-4S]0 to give [M3Fe-4S] clusters is slow (t1/2 > 10 min at room temperature, slower still if the protein is adsorbed on the electrode), whereas reaction with Tl(I) to produce [Tl3Fe-4S] is very rapid (t1/2 ≪ 1 s), suggesting that co-ordination of Tl does not require reorganization of the protein structure. Rates of formation of [3Fe-4S] from [M3Fe-4S] adducts increase sharply at high potentials, showing that metal release involves a labile ‘super-oxidized ’ [M3Fe-4S]3+ state.

scholarly journals The Encapsulation of Lycopene in Nanoliposomes Enhances Its Protective Potential in Methotrexate-Induced Kidney Injury Model

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Nenad Stojiljkovic ◽  
Sonja Ilic ◽  
Vladimir Jakovljevic ◽  
Nikola Stojanovic ◽  
Slavica Stojnev ◽  
...  
Keyword(s):  
Oxidative Damage ◽  
Structural Changes ◽  
Corn Oil ◽  
Kidney Tissue ◽  
Kidney Injury ◽  
Serum Urea ◽  
Morphological Alterations ◽  
Injury Model ◽  
Serum Biochemical ◽  
Degree Of Recovery

Methotrexate is an antimetabolic drug with a myriad of serious side effects including nephrotoxicity, which presumably occurs due to oxidative tissue damage. Here, we evaluated the potential protective effect of lycopene, a potent antioxidant carotenoid, given in two different pharmaceutical forms in methotrexate-induced kidney damage in rats. Serum biochemical (urea and creatinine) and tissue oxidative damage markers and histopathological kidney changes were evaluated after systemic administration of both lycopene dissolved in corn oil and lycopene encapsulated in nanoliposomes. Similar to previous studies, single dose of methotrexate induced severe functional and morphological alterations of kidneys with cell desquamation, tubular vacuolation, and focal necrosis, which were followed by serum urea and creatinine increase and disturbances of tissue antioxidant status. Application of both forms of lycopene concomitantly with methotrexate ameliorated changes in serum urea and creatinine and oxidative damage markers and markedly reversed structural changes of kidney tissue. Moreover, animals that received lycopene in nanoliposome-encapsulated form showed higher degree of recovery than those treated with free lycopene form. The findings of this study indicate that treatment with nanoliposome-encapsulated lycopene comparing to lycopene in standard vehicle has an advantage as it more efficiently reduces methotrexate-induced kidney dysfunction.

scholarly journals Oxidative damage to DNA: Inhibition of guanine damage

2006 ◽  
Vol 78 (12) ◽  
pp. 2297-2304 ◽  
Author(s):  
Sriram Kanvah ◽  
Gary B. Schuster
Keyword(s):  
Oxidative Damage ◽  
Structural Changes ◽  
Global Structure ◽  
Chemical Damage ◽  
Oxidation Of Dna ◽  
Anthraquinone Derivatives ◽  
Covalently Linked ◽  
The One ◽  
Oxidative Damage To Dna ◽  
Dna Inhibition

One-electron oxidation of DNA results in chemical damage to nucleobases, particularly guanine in multiple G sequences. Oxidation may be triggered by numerous events, including photosensitization. We describe studies of photoinduced oxidations of DNA triggered by irradiation of covalently linked anthraquinone derivatives under various conditions that affect the global structure of the DNA. These structural changes have subtle effects on the result of the one-electron oxidation.

Protein Film Voltammetry ofRhodobacterCapsulatusXanthine Dehydrogenase

2003 ◽  
Vol 125 (50) ◽  
pp. 15352-15358 ◽  
Author(s):  
Kondo François Aguey-Zinsou ◽  
Paul V. Bernhardt ◽  
Silke Leimkühler
Keyword(s):  
Protein Film ◽  
Protein Film Voltammetry

scholarly journals Mn Inhibits GSH Synthesis via Downregulation of Neuronal EAAC1 and Astrocytic xCT to Cause Oxidative Damage in the Striatum of Mice

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Xinxin Yang ◽  
Haibo Yang ◽  
Fengdi Wu ◽  
Zhipeng Qi ◽  
Jiashuo Li ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Oxidative Damage ◽  
Dependent Manner ◽  
Protein Levels ◽  
Key Factor ◽  
Protein Sulfhydryl ◽  
Mrna And Protein Expression ◽  
The Brain

Excessive manganese (Mn) can accumulate in the striatum of the brain following overexposure. Oxidative stress is a well-recognized mechanism in Mn-induced neurotoxicity. It has been proven that glutathione (GSH) depletion is a key factor in oxidative damage during Mn exposure. However, no study has focused on the dysfunction of GSH synthesis-induced oxidative stress in the brain during Mn exposure. The objective of the present study was to explore the mechanism of Mn disruption of GSH synthesis via EAAC1 and xCT in vitro and in vivo. Primary neurons and astrocytes were cultured and treated with different doses of Mn to observe the state of cells and levels of GSH and reactive oxygen species (ROS) and measure mRNA and protein expression of EAAC1 and xCT. Mice were randomly divided into seven groups, which received saline, 12.5, 25, and 50 mg/kg MnCl2, 500 mg/kg AAH (EAAC1 inhibitor) + 50 mg/kg MnCl2, 75 mg/kg SSZ (xCT inhibitor) + 50 mg/kg MnCl2, and 100 mg/kg NAC (GSH rescuer) + 50 mg/kg MnCl2 once daily for two weeks. Then, levels of EAAC1, xCT, ROS, GSH, malondialdehyde (MDA), protein sulfhydryl, carbonyl, 8-hydroxy-2-deoxyguanosine (8-OHdG), and morphological and ultrastructural features in the striatum of mice were measured. Mn reduced protein levels, mRNA expression, and immunofluorescence intensity of EAAC1 and xCT. Mn also decreased the level of GSH, sulfhydryl, and increased ROS, MDA, 8-OHdG, and carbonyl in a dose-dependent manner. Injury-related pathological and ultrastructure changes in the striatum of mice were significantly present. In conclusion, excessive exposure to Mn disrupts GSH synthesis through inhibition of EAAC1 and xCT to trigger oxidative damage in the striatum.

Resonance Raman spectroscopy of Azotobacter vinelandii ferredoxin I

FEBS Letters ◽  
1983 ◽  
Vol 163 (2) ◽  
pp. 212-216 ◽  
Author(s):  
Marc Lutz ◽  
Jean-Marc Moulis ◽  
Jacques Meyer
Keyword(s):  
Raman Spectroscopy ◽  
Azotobacter Vinelandii ◽  
Resonance Raman Spectroscopy ◽  
Resonance Raman ◽  
Ferredoxin I

scholarly journals Site-directed mutagenesis of Azotobacter vinelandii ferredoxin I: [Fe-S] cluster-driven protein rearrangement.

1990 ◽  
Vol 87 (2) ◽  
pp. 598-602 ◽  
Author(s):  
A. E. Martin ◽  
B. K. Burgess ◽  
C. D. Stout ◽  
V. L. Cash ◽  
D. R. Dean ◽  
...  
Keyword(s):  
Azotobacter Vinelandii ◽  
Site Directed Mutagenesis ◽  
Directed Mutagenesis ◽  
Ferredoxin I
Sign in / Sign up

Export Citation Format

Share Document