Related Experiment Video
Updated: Jun 2, 2026
09:47
Imaging of mtHyPer7, a Ratiometric Biosensor for Mitochondrial Peroxide, in Living Yeast Cells
Published on: June 2, 2023
Characterization of dye-decolorizing peroxidases from Rhodococcus jostii RHA1
Joseph N Roberts1, Rahul Singh, Jason C Grigg
1Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
Biochemistry
|May 4, 2011
Summary
Rhodococcus jostii RHA1
Area of Science:
- Biochemistry
- Enzymology
- Microbiology
Background:
- Rhodococcus jostii RHA1 possesses two dye-decolorizing peroxidases (DyPs): DypA and DypB.
- DypA is predicted to be periplasmic, while DypB is implicated in lignin degradation.
Purpose of the Study:
- To characterize the biochemical and structural properties of DypA and DypB.
- To understand the distinct roles and mechanisms of these two DyPs in Rhodococcus jostii RHA1.
Main Methods:
- Steady-state kinetic studies
- Electron paramagnetic resonance (EPR) spectroscopy
- X-ray crystallography
Main Results:
- DypA exhibited higher specificity for Reactive Blue 4, while DypB showed greater specificity for ABTS and Mn(II) oxidation.
- EPR spectroscopy revealed distinct resting-state signals for DypA (rhombic) and DypB (axial).
- DypB formed a stable, green-colored intermediate upon reaction with H2O2, suggesting a protein-based radical.
Conclusions:
- DypA and DypB display differential substrate specificities and distinct reaction mechanisms.
- The crystal structure of DypB provides insights into its catalytic site and potential for Mn(II) binding.
- Understanding DypB's structure-function relationship can aid in engineering it for enhanced lignocellulose degradation.
More Related Videos
08:31Anaerobic Protein Purification and Kinetic Analysis via Oxygen Electrode for Studying DesB Dioxygenase Activity and Inhibition
Published on: October 3, 2018
08:57Simultaneous Measurement of Superoxide/Hydrogen Peroxide and NADH Production by Flavin-containing Mitochondrial Dehydrogenases
Published on: February 24, 2018
Related Concept Videos
01:29The Photochemical Reaction Center
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
01:11Channel Rhodopsins
Most organisms use photoreceptors to sense and respond to light. Examples of photoreceptors include bacteriorhodopsins and bacteriophytochromes in some bacteria, phytochromes in plants, and rhodopsins in the photoreceptor cells of the vertebral retina. The light-sensitive property of these receptors is because of the bound chromophores, such as bilin in the phytochromes and retinal in the rhodopsins.
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
01:28Anoxygenic Phototrophic Bacteria
Anoxygenic phototrophic bacteria are a diverse group of microorganisms that perform photosynthesis without producing oxygen. They primarily include purple sulfur bacteria, purple nonsulfur bacteria, green sulfur bacteria, and green nonsulfur bacteria. These bacteria are classified into the Gammaproteobacteria, Alphaproteobacteria, Betaproteobacteria, Chlorobi, and Chloroflexi lineages, each with distinct physiological and ecological adaptations.Purple sulfur bacteria belong to the...
01:17Oxidation of Phenols to Quinones
In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...
01:26Differential Staining Technique
Differential staining is an essential microbiological technique that exploits variations in cell wall structures to classify and identify microorganisms. It facilitates the distinction of bacteria, aiding in diagnostic and research applications. Two of the most widely used differential staining methods are Gram staining and acid-fast staining, both of which rely on the chemical and structural differences in bacterial cell walls.Gram Staining TechniqueGram staining differentiates bacteria by...
01:21Cell Polarization by Rho Proteins
Cell polarity is the asymmetric distribution of cellular and membrane components, making one side of the cell different from the other. This polarity is essential to many processes such as embryogenesis, axon migration, glucose transport across epithelial cells, and directional cell migration. A migrating cell responds to intracellular or extracellular signals via molecular cascades that reorganize the actin cytoskeleton to establish this polarity. In these cells, the Rho family proteins Cdc42,...