The principle mitochondrial target where the respiratory inhibitors CO, CN(-), and NO act in the execution of their acute toxic effects is complex IV of the electron-transport chain, cytochrome c oxidase. However, there is a paucity of studies in the literature regarding the concerted effects of such poisons. Accordingly, the combined inhibitory effects of CO + CN(-), NO + CN(-), and NO + CO on the activity of cytochrome c oxidase preparations are reported. Only in the case of CO + CN(-) do the effects of the two inhibitors seem to be additive as expected. NO appears to be antagonistic toward the effects of the other two inhibitors; that is, the effects of both CO an CN(-) on enzyme activity are ameliorated by NO when present. To further clarify these observations, the ligand substitutions of heme-bound CN(-) by NO in cytochrome c oxidase and hemoglobin have also been briefly investigated. These results suggest that displacement of CN(-) from the ferric hemoproteins by NO is rate-limited by heme reduction-and in the case of the enzyme, the presence of nonligand-binding electron-transfer centers facilitates the reaction. The findings are discussed in relation to the idea that NO does not behave as a classic reversible (by dissociation) inhibitor.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2773210 | PMC |
| http://dx.doi.org/10.1021/tx800140y | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Liver fatty acid binding protein FABP1 transfers substrates to cytochrome P450 4A11 for catalysis.
J Biol Chem
January 2025
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, United States. Electronic address:
Cytochrome P450 (P450) 4A11 is a human P450 family 4 ω-oxidase that selectively catalyzes the hydroxylation of the terminal methyl group of fatty acids. Cytosolic lipids are the substrates for the enzyme but are considered to be primarily bound in cells by liver fatty acid binding protein (FABP1). Lipid binding to recombinant FABP1 with a fluorophore displacement assay showed substantial preference of FABP1 for ≥16-carbon fatty acids (K < 70 nM).
View Article and Find Full Text PDFExploring Dietary Composition in an Invasive Apple Snail From Different Habitats Combining With Intestinal Microbiota and Metabolomics.
Integr Zool
January 2025
College of Life Sciences, Nanjing Forestry University, Nanjing, China.
Article Synopsis
- Pomacea canaliculata is an invasive aquatic species with varying dietary habits and intestinal microbiota across different habitats (pond, river, ditch).
- This study utilized gene sequencing and metabolomics to analyze intestinal samples, revealing the highest dietary diversity in ditches and significant differences between male and female diets in ponds.
- The findings indicate that changes in diet affect intestinal microbiota and metabolic pathways, helping to explain how P. canaliculata adapts physiologically to diverse environments, which is crucial for understanding its impact on aquatic ecosystems.
Dichlormid protect wheat from fomesafen residual injury by increasing PPO expression and the photosynthesis characterize.
Ecotoxicol Environ Saf
January 2025
College of Resources and Environment, Henan Institute of Science and Technology, Xinxiang, Henan Province 453003, China. Electronic address:
Fomesafen is a herbicide with long persistence in soil, causing damage to succeeding crops. Dichlormid is a widely used safener protecting maize from chloroacetanilide and thiocarbamate injury. We found that dichlormid treatment could restore the growth of wheat seedlings exposed to fomesafen stress.
View Article and Find Full Text PDFThe genes are important for growth in the presence of sphingosine by promoting sphingosine metabolism.
Microbiology (Reading)
January 2025
Department of Microbiology and Molecular Genetics, Larner College of Medicine, University of Vermont, Burlington, USA.
Sphingoid bases, including sphingosine, are important components of the antimicrobial barrier at epithelial surfaces where they can cause growth inhibition and killing of susceptible bacteria. is a common opportunistic pathogen that is less susceptible to sphingosine than many Gram-negative bacteria. Here, we determined that the deletion of the operon reduced growth in the presence of sphingosine.
View Article and Find Full Text PDFMapping mitochondrial morphology and function: COX-SBFSEM reveals patterns in mitochondrial disease.
Commun Biol
January 2025
Wellcome Centre for Mitochondrial Research, Translational and Clinical Research, Faculty of Medical Sciences, Newcastle University, Newcastle, UK.
Mitochondria play a crucial role in maintaining cellular health. It is interesting that the shape of mitochondria can vary depending on the type of cell, mitochondrial function, and other cellular conditions. However, there are limited studies that link functional assessment with mitochondrial morphology evaluation at high magnification, even fewer that do so in situ and none in human muscle biopsies.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!