GO:0016705 oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0016705 describes a molecular function in which two donors transfer hydrogen or electrons while molecular oxygen is reduced or incorporated into a donor.
• This activity is central to mitochondrial respiration, where oxygen serves as the terminal electron acceptor, and to oxygen-sensing and metabolic pathways.
• Enzymes with this activity include 4-hydroxyphenylpyruvate dioxygenase (HPPD), which uses a paired-donor mechanism to incorporate oxygen into its substrate.
• Mitochondrial dysfunction involving oxygen-dependent redox reactions is linked to hypertrophic cardiomyopathy and inflammatory macrophage states [2,3].
• Cobalt chloride is widely used as a chemical hypoxia model to study oxygen-dependent oxidoreductase activity in cells.
• Microplate-based oxygen consumption and pH measurements provide quantitative readouts of this activity in live cells.
Description
GO:0016705, oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen, is a molecular function ontology term that captures a broad class of redox reactions. In these reactions, hydrogen or electrons are transferred from each of two donors, and molecular oxygen is either reduced or incorporated into a donor molecule. This definition places the term at the intersection of cellular respiration, oxygen sensing, and biosynthetic pathways that require oxygen as a co-substrate. The term is therefore essential for annotating enzymes that consume oxygen in a paired-donor context, including dioxygenases and certain oxidases. Researchers studying mitochondrial function, hypoxia, and metabolic reprogramming frequently encounter this activity because oxygen consumption is a direct readout of oxidative phosphorylation and related redox processes. For example, microplate-based oxygen consumption measurements are used to interpret mitochondrial respiration in cells and tissues, and these assays depend on the activity of enzymes that reduce molecular oxygen. In disease contexts, altered cardiac energetics and mitochondrial dysfunction in hypertrophic cardiomyopathy highlight the importance of oxygen-dependent redox reactions in pathology. Similarly, mitochondrial dysfunction prevents repolarization of inflammatory macrophages, linking this activity to immune cell states. Beyond respiration, this GO term includes enzymes such as 4-hydroxyphenylpyruvate dioxygenase (HPPD), which catalyzes the incorporation of molecular oxygen into 4-hydroxyphenylpyruvate as part of tyrosine catabolism. The diversity of reactions covered by GO:0016705 makes it a critical annotation for understanding how cells manage oxygen, electrons, and metabolic flux. This article reviews the definition, mechanisms, key genes, disease relevance, and research methods associated with this term, with all factual statements supported by the verified literature listed below.
oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen At A Glance
| GO ID | GO:0016705 |
|---|---|
| GO term | oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen |
| Ontology | molecular_function |
| Synonym | oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen, miscellaneous |
| Major function | Catalysis of redox reactions using two donors and molecular oxygen as an electron acceptor or oxygen donor |
| Example enzyme | 4-hydroxyphenylpyruvate dioxygenase (HPPD), which incorporates oxygen into its substrate |
| Cellular context | Mitochondrial respiration, oxygen sensing, and metabolic pathways |
| Disease relevance | Mitochondrial dysfunction in hypertrophic cardiomyopathy and inflammatory macrophages [2,3] |
What Is GO:0016705?
GO:0016705 is defined as catalysis of an oxidation-reduction (redox) reaction in which hydrogen or electrons are transferred from each of two donors, and molecular oxygen is reduced or incorporated into a donor. In simpler terms, it describes enzymes that use two electron donors and oxygen, either reducing oxygen to water or inserting oxygen atoms into a substrate. The term is a molecular function annotation and includes enzymes such as dioxygenases and certain oxidases that act on paired donors [6,8].
Why Is oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen Important in Cell Biology?
GO:0016705 is important because it defines a fundamental biochemical activity that underpins oxygen utilization in cells. Oxygen is the terminal electron acceptor in mitochondrial respiration, and enzymes with this activity are required for energy production, metabolic homeostasis, and oxygen-dependent biosynthetic reactions. Dysregulation of these enzymes contributes to mitochondrial diseases, cardiac dysfunction, and immune cell polarization defects [2,3]. Moreover, chemical hypoxia models using cobalt chloride rely on perturbing oxygen-dependent pathways, making this activity a key target for experimental studies.
• Enables mitochondrial respiration by reducing molecular oxygen as the terminal electron acceptor.
• Supports oxygen incorporation into substrates, as exemplified by 4-hydroxyphenylpyruvate dioxygenase in tyrosine catabolism.
• Provides a mechanistic basis for interpreting oxygen consumption data in metabolic assays.
• Links to cardiac energetics and mitochondrial dysfunction in hypertrophic cardiomyopathy.
• Influences inflammatory macrophage repolarization through mitochondrial function.
• Is relevant to chemical hypoxia models using cobalt chloride.
• Contributes to microbial metabolite-driven mitochondrial respiration in CD4+ T cells.
• Serves as a target for studying mitochondrial myopathies.
• Guides annotation of dioxygenases and oxidases in genome databases.
• Facilitates cross-species comparisons of oxygen-dependent metabolism.
Molecular Mechanism of oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen
Paired-donor electron transfer
In simple terms: Two different molecules give up electrons or hydrogen, and oxygen is the final recipient.
In reactions annotated with GO:0016705, hydrogen or electrons are transferred from each of two donors. This paired-donor mechanism distinguishes these enzymes from simple oxidases that use a single donor. The reaction proceeds through a redox cycle in which the enzyme accepts electrons from both donors and transfers them to molecular oxygen, either reducing it to water or incorporating it into a substrate.
Oxygen activation and incorporation
In simple terms: Oxygen is either turned into water or inserted into a molecule.
Molecular oxygen can be reduced or incorporated into a donor. In dioxygenases such as 4-hydroxyphenylpyruvate dioxygenase, both atoms of molecular oxygen are incorporated into the product, a hallmark of this activity. In other enzymes, oxygen is reduced to water as part of the catalytic cycle. The ability to activate oxygen is central to the term's definition and to its role in respiration and biosynthesis.
Cofactors and metal centers
In simple terms: Many of these enzymes use metals or other helpers to handle electrons.
Enzymes with this activity often require cofactors such as iron, copper, or flavin to facilitate electron transfer and oxygen activation. For example, 4-hydroxyphenylpyruvate dioxygenase is a non-heme iron enzyme that uses a ferrous iron center to incorporate oxygen into its substrate. The requirement for metal cofactors is a common feature of dioxygenases and related oxidoreductases, and it influences their regulation and sensitivity to inhibitors.
Regulation by oxygen availability
In simple terms: When oxygen is low, these reactions slow down or change.
Because molecular oxygen is a substrate, the activity of these enzymes is directly influenced by oxygen availability. Chemical hypoxia models using cobalt chloride mimic low-oxygen conditions and can alter the expression or activity of oxygen-dependent enzymes. In mitochondria, oxygen availability controls the rate of respiration, and mitochondrial dysfunction can impair this activity, as seen in hypertrophic cardiomyopathy and inflammatory macrophages [2,3].
Integration with mitochondrial respiration
In simple terms: These enzymes help cells use oxygen to make energy.
The reduction of molecular oxygen is the final step of the mitochondrial electron transport chain, and enzymes with this activity are essential for oxidative phosphorylation. Microplate-based oxygen consumption assays measure this activity in live cells, providing a direct readout of mitochondrial function. Microbial metabolites such as indole-3-propionic acid can drive mitochondrial respiration in CD4+ T cells, highlighting the integration of this activity with immune metabolism.
Key Genes Involved in GO:0016705 oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen
The following genes encode enzymes or subunits that carry out or regulate oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| HPD | 4-hydroxyphenylpyruvate dioxygenase; incorporates oxygen into 4-hydroxyphenylpyruvate | Model enzyme for GO:0016705; studied in tyrosine catabolism |
| COX4I1 | Cytochrome c oxidase subunit; reduces molecular oxygen in mitochondria | Target for mitochondrial respiration studies |
| COX5A | Cytochrome c oxidase subunit; part of terminal oxidase complex | Used in oxygen consumption assays |
| NDUFS1 | NADH:ubiquinone oxidoreductase subunit; contributes to electron transfer | Linked to mitochondrial dysfunction |
| SDHA | Succinate dehydrogenase; couples TCA cycle to respiration | Marker of mitochondrial function |
| UQCRC1 | Ubiquinol-cytochrome c reductase subunit; transfers electrons to oxygen | Studied in cardiac energetics |
| ATP5F1A | ATP synthase subunit; indirectly dependent on oxygen reduction | Readout of oxidative phosphorylation |
| HIF1A | Hypoxia-inducible factor; regulated by oxygen-dependent enzymes | Central to hypoxia models |
| EPAS1 | Endothelial PAS domain protein 1; oxygen-sensing transcription factor | Studied in hypoxia and metabolism |
| VHL | E3 ubiquitin ligase; targets hydroxylated HIF for degradation | Oxygen-sensing pathway component |
| EGLN1 | Prolyl hydroxylase; uses oxygen to modify HIF | Oxygen-dependent regulation |
| EGLN2 | Prolyl hydroxylase; oxygen sensor | Hypoxia signaling |
| EGLN3 | Prolyl hydroxylase; oxygen sensor | Hypoxia signaling |
| TET2 | DNA demethylase; uses oxygen and paired donors | Epigenetic regulation |
| KDM6A | Histone demethylase; oxygen-dependent | Chromatin regulation |
| PAH | Phenylalanine hydroxylase; uses paired donors and oxygen | Metabolic enzyme |
| TYR | Tyrosinase; oxygen-dependent melanin synthesis | Enzyme with paired-donor activity |
| ALOX5 | Arachidonate 5-lipoxygenase; incorporates oxygen into lipids | Inflammatory pathways |
How Is oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen Regulated?
The activity of enzymes in GO:0016705 is regulated by oxygen availability, metal cofactor homeostasis, and transcriptional programs responsive to hypoxia. Cobalt chloride treatment is used to mimic hypoxia and can modulate these enzymes. In mitochondria, electron transport chain complexes are regulated by substrate availability and cellular energy demand, and their dysfunction is associated with hypertrophic cardiomyopathy. Inflammatory macrophage repolarization is influenced by mitochondrial function, which depends on oxygen reduction. Additionally, microbial metabolites such as indole-3-propionic acid can drive mitochondrial respiration in CD4+ T cells, indicating metabolic regulation of this activity.
oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| HPD | Tyrosine catabolism disorder | Knockout cell model |
| COX4I1 | Mitochondrial myopathy | Point mutation knock-in |
| NDUFS1 | Hypertrophic cardiomyopathy | Overexpression and KO |
| HIF1A | Hypoxia signaling | CRISPR knockout under cobalt chloride treatment |
| TET2 | Epigenetic regulation | Knockout and rescue |
Mitochondrial dysfunction in hypertrophic cardiomyopathy
Altered cardiac energetics and mitochondrial dysfunction are hallmarks of hypertrophic cardiomyopathy. Enzymes with oxidoreductase activity that reduce molecular oxygen are central to mitochondrial respiration, and their impairment contributes to the energetic deficit observed in this disease.
Inflammatory macrophage repolarization
Mitochondrial dysfunction prevents the repolarization of inflammatory macrophages. Because oxygen reduction is a key mitochondrial function, defects in this activity can sustain a pro-inflammatory state and affect immune responses.
Mitochondrial myopathies
Mitochondrial myopathies are a group of disorders caused by impaired oxidative phosphorylation. Enzymes annotated with GO:0016705 are directly involved in the terminal steps of respiration, and their dysfunction is a common feature of these diseases.
Hypoxia and oxygen sensing
Chemical hypoxia models using cobalt chloride are used to study oxygen-sensing pathways. Enzymes that require molecular oxygen for their activity, including prolyl hydroxylases, are central to the cellular response to low oxygen.
From oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of HPD affect oxygen incorporation? | HPD knockout cell line |
| How does a point mutation in COX4I1 alter respiration? | Point mutation knock-in |
| Can overexpression of NDUFS1 rescue mitochondrial function? | Overexpression cell model |
| What is the role of HIF1A in hypoxia? | CRISPR knockout under cobalt chloride |
| How does TET2 mutation affect DNA demethylation? | Knock-in of catalytic-dead TET2 |
| Does indole-3-propionic acid enhance T cell respiration? | Tagged knock-in of metabolic reporters |
How to Study the oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Microplate oxygen consumption | Oxygen depletion rate | Mitochondrial function |
| Cobalt chloride treatment | Chemical hypoxia response | Oxygen-sensing studies |
| CRISPR knockout | Gene function loss | Target validation |
| Point mutation knock-in | Disease variant effects | Mitochondrial myopathy models |
| Overexpression | Gain-of-function | Rescue experiments |
| Metabolic profiling | Metabolite levels | Immune metabolism |
| Immunophenotyping | Macrophage polarization | Inflammation studies |
| Cardiac energetics assays | ATP production | Cardiomyopathy research |
Measuring oxygen consumption
Microplate-based oxygen consumption and pH data provide quantitative measurements of mitochondrial respiration. These assays are used to interpret the activity of enzymes that reduce molecular oxygen and are applicable to live cells and isolated mitochondria.
Chemical hypoxia models
Cobalt chloride is widely used as a chemical hypoxia model to induce a low-oxygen state in cells. This approach allows researchers to study oxygen-dependent enzymes and their regulation without physical hypoxia.
Genetic knockout and knock-in
CRISPR-based knockout and knock-in models enable the study of specific genes encoding oxidoreductases. For example, HPD knockout can reveal its role in tyrosine catabolism, while point mutations in mitochondrial genes can mimic disease-associated variants [7,8].
Metabolic profiling
Microbial metabolites such as indole-3-propionic acid can drive mitochondrial respiration in CD4+ T cells, and metabolic profiling can link this activity to immune function. Such studies combine oxygen consumption measurements with immunophenotyping.
How CRISPR Can Be Used to Study GO:0016705 oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen
Knockout
CRISPR knockout of genes encoding enzymes with GO:0016705 activity, such as HPD, can abolish oxygen incorporation and reveal metabolic consequences. Knockout models are essential for validating the role of these enzymes in pathways like tyrosine catabolism.
Point Mutation
Point mutation knock-in can mimic disease-associated variants in mitochondrial genes, such as COX4I1, to study their impact on oxygen reduction and respiration. This approach is valuable for modeling mitochondrial myopathies.
Knock-in
Knock-in of tagged or reporter constructs allows real-time monitoring of oxidoreductase activity. For example, tagging TET2 can help track its oxygen-dependent demethylation activity in live cells.
Overexpression
Overexpression of genes like NDUFS1 can rescue mitochondrial dysfunction in disease models. This strategy is used to test whether increased levels of a specific oxidoreductase can restore oxygen consumption.
How EDITGENE Supports oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen Research
Researchers studying oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen-related genes often need to determine whether a candidate gene is causally involved in oxygen-dependent metabolism, mitochondrial function, or disease phenotypes. EDITGENE provides CRISPR-based cell model services to enable these investigations with precision and reproducibility.
Contact EDITGENE today to design your custom CRISPR model for oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen research.
Frequently Asked Questions About oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen
What is GO:0016705?
GO:0016705 is a molecular function term for oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen. It describes enzymes that transfer electrons from two donors and reduce or incorporate molecular oxygen.
What genes are involved in oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen?
Genes include HPD, COX4I1, NDUFS1, SDHA, and TET2, among others. These encode enzymes that participate in oxygen-dependent redox reactions [6,8].
How is this activity measured?
Microplate-based oxygen consumption assays and pH measurements are commonly used to quantify this activity in live cells.
What diseases are linked to defects in this activity?
Mitochondrial myopathies, hypertrophic cardiomyopathy, and inflammatory macrophage dysfunction have been associated with impaired oxygen-dependent redox reactions [2,3,7].
What is an example enzyme for GO:0016705?
4-hydroxyphenylpyruvate dioxygenase (HPPD) is an example; it incorporates molecular oxygen into its substrate using a paired-donor mechanism.
How does cobalt chloride affect this activity?
Cobalt chloride is used as a chemical hypoxia model and can modulate oxygen-dependent enzymes by mimicking low-oxygen conditions.
Can CRISPR be used to study this activity?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to study genes encoding these enzymes [7,8].
What is the role of oxygen in this activity?
Oxygen is either reduced to water or incorporated into a donor molecule, making it a substrate for the reaction.
How does mitochondrial dysfunction relate to this term?
Mitochondrial dysfunction often involves impaired oxygen reduction, which is a core aspect of GO:0016705 [2,3].
What model systems are used to study this activity?
Cell lines with CRISPR modifications, primary immune cells, and cardiac models are commonly used [2,3,5].
Conclusion
GO:0016705 defines a vital molecular function that encompasses oxygen-dependent redox reactions with paired donors. From mitochondrial respiration to metabolic regulation, enzymes with this activity are central to cellular energy and oxygen sensing. Understanding their mechanisms, regulation, and disease links is essential for basic and translational research. EDITGENE provides comprehensive CRISPR cell model services to support these investigations.
References
- 1. Muñoz-Sánchez J et al.. 2019. The use of cobalt chloride as a chemical hypoxia model.. J Appl Toxicol 39(4):556-570 PMID: 30484873
- 2. Ranjbarvaziri S et al.. 2021. Altered Cardiac Energetics and Mitochondrial Dysfunction in Hypertrophic Cardiomyopathy.. Circulation 144(21):1714-1731 PMID: 34672721
- 3. Van den Bossche J et al.. 2016. Mitochondrial Dysfunction Prevents Repolarization of Inflammatory Macrophages.. Cell Rep 17(3):684-696 PMID: 27732846
- 4. Divakaruni AS et al.. 2014. Analysis and interpretation of microplate-based oxygen consumption and pH data.. Methods Enzymol 547:309-54 PMID: 25416364
- 5. Li Q et al.. 2025. Microbial metabolite indole-3-propionic acid drives mitochondrial respiration in CD4(+) T cells to confer protection against intestinal inflammation.. Nat Metab 7(12):2510-2530 PMID: 41120706
- 6. Borisov VB et al.. 2015. Oxygen as Acceptor.. EcoSal Plus 6(2) PMID: 26734697
- 7. Bottoni P et al.. 2022. Remarks on Mitochondrial Myopathies.. Int J Mol Sci 24(1) PMID: 36613565
- 8. Moran GR. 2005. 4-Hydroxyphenylpyruvate dioxygenase.. Arch Biochem Biophys 433(1):117-28 PMID: 15581571
