GO:0016727 oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0016727 describes a molecular function in which a CH2 group donates hydrogen or electrons to molecular oxygen, producing water or hydrogen peroxide.
• Enzymes with this activity include molybdenum-cofactor-dependent hydroxylases such as xanthine oxidoreductase and flavin-dependent oxidases that activate O2 for CH2 oxidation.
• Retinol saturase is a CH-CH2 oxidoreductase that uses oxygen as an acceptor and has been linked to lipid metabolism and cellular stress responses.
• Light-dependent protochlorophyllide oxidoreductase is a CH2-group oxidoreductase that reduces protochlorophyllide using oxygen as an electron acceptor in photosynthetic organisms.
• Dysregulation of CH2-oxidizing enzymes contributes to drug metabolism, hyperuricemia, and oxidative stress-related pathologies.
• CRISPR knockout, point-mutation, knock-in, and overexpression models are essential for dissecting the physiological roles of GO:0016727 enzymes.
Description
GO:0016727, oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor, is a molecular function defined by the catalytic oxidation of a CH2 group using molecular oxygen as the electron acceptor. This activity is central to redox biochemistry because it couples the activation of a relatively inert C-H bond to the reduction of O2, often generating reactive oxygen species or water as byproducts. Enzymes carrying this activity are widespread across prokaryotes, plants, and mammals, where they participate in purine catabolism, lipid desaturation, chlorophyll biosynthesis, and xenobiotic detoxification. Understanding GO:0016727 is therefore critical for researchers studying oxidative stress, metabolic disorders, and drug metabolism. The catalytic diversity of these enzymes arises from distinct cofactors, including molybdenum cofactor, flavin adenine dinucleotide (FAD), and iron-sulfur clusters, which tune the redox potential for CH2 oxidation. In this article, we integrate authoritative QuickGO annotation with verified PubMed literature to provide a research-grade overview of GO:0016727, its gene families, disease relevance, and CRISPR-based experimental strategies.
oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor At A Glance
| GO ID | GO:0016727 |
|---|---|
| GO term | oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor |
| Ontology | molecular_function |
| Synonym | None listed in QuickGO |
| Major function | Catalysis of redox reactions where a CH2 group donates hydrogen/electrons to O2 |
| Cofactors | Molybdenum cofactor, FAD, iron-sulfur clusters, heme |
| Representative enzymes | Xanthine oxidoreductase, retinol saturase, protochlorophyllide oxidoreductase |
| Biological contexts | Purine catabolism, lipid metabolism, chlorophyll biosynthesis, drug oxidation |
What Is GO:0016727?
GO:0016727 is a molecular function term describing catalysis of an oxidation-reduction reaction in which a CH2 group acts as a hydrogen or electron donor and reduces an oxygen molecule. In other words, the enzyme abstracts hydrogen from a methylene carbon and transfers electrons to O2, forming water or hydrogen peroxide depending on the enzyme class. This definition distinguishes GO:0016727 from other oxidoreductases that use NAD+, NADP+, or cytochrome acceptors rather than oxygen.
Why Is oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor Important in Cell Biology?
GO:0016727 is important because it defines a fundamental redox strategy for activating molecular oxygen to oxidize CH2 groups, a reaction that underlies purine degradation, retinol saturation, chlorophyll synthesis, and xenobiotic metabolism. Dysregulation of these enzymes can lead to hyperuricemia, oxidative stress, and altered drug clearance, making them attractive targets for therapeutic intervention. Moreover, the ability to engineer CH2-oxidizing enzymes through CRISPR-based approaches enables precise dissection of their roles in health and disease.
• GO:0016727 enzymes catalyze key steps in purine catabolism, including xanthine oxidation to uric acid.
• Retinol saturase, a CH2 oxidoreductase, modulates lipid signaling and cellular stress responses.
• Light-dependent protochlorophyllide oxidoreductase is essential for chlorophyll biosynthesis in plants.
• Molybdenum-cofactor enzymes with this activity are involved in drug metabolism and detoxification.
• Flavoenzymes using oxygen as an acceptor contribute to alcohol oxidation and redox homeostasis.
• Nitrogenase-like enzymes that reduce stable multibonds share mechanistic features with CH2 oxidoreductases.
• Polyamine metabolism and autophagy intersect with oxidative enzymes in skeletal muscle aging.
• Genetic engineering of eugenol biosynthesis in aspen involves oxidative enzymes acting on CH2 groups.
• CRISPR screens can identify genes required for GO:0016727-dependent metabolic pathways.
• Targeting CH2-oxidizing enzymes may offer therapeutic strategies for hyperuricemia and oxidative stress disorders.
What Happens During oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor?
Substrate binding and CH2 activation
In simple terms: The enzyme grabs a molecule that has a CH2 group and prepares it for oxidation.
The first step involves binding of the substrate containing a CH2 group to the enzyme active site, where cofactors such as molybdenum cofactor or FAD position the methylene carbon for hydrogen abstraction. This binding often induces conformational changes that lower the activation energy for C-H bond cleavage.
Hydrogen abstraction and electron transfer
In simple terms: Hydrogen is pulled off the CH2 group and its electrons are sent to oxygen.
The enzyme abstracts hydrogen from the CH2 group, generating a substrate radical or carbocation intermediate, while the electrons are transferred through the cofactor to molecular oxygen. In molybdenum-containing enzymes, the metal center cycles between Mo(VI) and Mo(IV) states during this transfer.
Oxygen reduction and product release
In simple terms: Oxygen accepts the electrons and becomes water or hydrogen peroxide, and the oxidized product is released.
Molecular oxygen is reduced to water or hydrogen peroxide, depending on the enzyme, and the oxidized substrate is released from the active site. This step regenerates the enzyme for subsequent catalytic cycles.
Cofactor regeneration and catalytic turnover
In simple terms: The enzyme resets its cofactor so it can start another reaction.
After product release, the cofactor is re-oxidized by oxygen or other electron acceptors, allowing continuous catalytic turnover. In some enzymes, such as xanthine oxidoreductase, the molybdenum cofactor is regenerated through intramolecular electron transfer to FAD and then to oxygen.
Key Genes Involved in GO:0016727 oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor
The following genes encode enzymes or subunits associated with GO:0016727 activity, based on verified literature and QuickGO annotations.
| Gene | Major Role | Research Relevance |
|---|---|---|
| XDH | Xanthine dehydrogenase/oxidase; oxidizes xanthine to uric acid using O2 | Drug metabolism, hyperuricemia, gout |
| XDH | Molybdenum cofactor enzyme with CH2 oxidation | Redox biology, oxidative stress |
| RETSAT | Retinol saturase; saturates retinol to dihydroretinol using O2 | Lipid metabolism, cellular stress |
| POR | Protochlorophyllide oxidoreductase; light-dependent CH2 reduction | Chlorophyll biosynthesis, plant biology |
| PORA | Protochlorophyllide oxidoreductase A | Photosynthesis research |
| PORB | Protochlorophyllide oxidoreductase B | Photosynthesis research |
| PORC | Protochlorophyllide oxidoreductase C | Photosynthesis research |
| AOX1 | Alternative oxidase; oxidizes ubiquinol with O2 | Plant respiration, stress |
| MOXD1 | Monooxygenase DBH-like 1; CH2 oxidation | Neurobiology, oxidative metabolism |
| DBH | Dopamine beta-hydroxylase; oxidizes CH2 to CHOH using O2 | Neurotransmitter synthesis |
| PAOX | Polyamine oxidase; oxidizes CH2 groups in polyamines | Polyamine metabolism, aging |
| SMOX | Spermine oxidase; CH2 oxidation with O2 | Polyamine catabolism, cancer |
| LOX | Lipoxygenase; oxidizes CH2 in polyunsaturated fatty acids | Inflammation, lipid signaling |
| COX | Cyclooxygenase; oxidizes CH2 in arachidonic acid | Inflammation, pain |
| NIT1 | Nitrilase-like enzyme; CH2 oxidation | Plant hormone metabolism |
| EGS | Eugenol synthase; oxidative CH2 conversion | Plant specialized metabolism |
| CYP | Cytochrome P450; CH2 hydroxylation with O2 | Drug metabolism, toxicology |
| FMO | Flavin-containing monooxygenase; CH2 oxidation | Drug metabolism, detoxification |
How Is oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor Regulated?
GO:0016727 activity is regulated at multiple levels. Transcriptional control of genes such as XDH and RETSAT responds to metabolic and oxidative stress signals. Post-translational modifications, including phosphorylation and proteolytic cleavage, modulate enzyme activity; for example, xanthine oxidoreductase can be converted from dehydrogenase to oxidase form by reversible sulfhydryl oxidation or proteolysis. Cofactor availability, particularly molybdenum cofactor and FAD, also limits catalytic capacity. In plants, light-dependent protochlorophyllide oxidoreductase is regulated by light and developmental cues. Polyamine oxidases are regulated by polyamine levels and autophagy-related signaling in skeletal muscle.
oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| XDH | Gout, hyperuricemia, drug metabolism | Xdh knockout mouse; point-mutation knock-in |
| RETSAT | Metabolic disorders, oxidative stress | Retsat knockout and overexpression cell lines |
| DBH | Autonomic dysfunction, neurodegeneration | Dbh knockout mouse; tagged knock-in |
| PAOX | Polyamine-related aging, cancer | Paox knockout; CRISPR library screening |
| POR | Chlorophyll biosynthesis defects | Plant POR knockout; point-mutation complementation |
Hyperuricemia and gout
Xanthine oxidoreductase, a GO:0016727 enzyme, catalyzes the terminal steps of purine catabolism to produce uric acid; overactivity leads to hyperuricemia and gout. Inhibitors such as allopurinol target this activity, demonstrating its clinical relevance.
Oxidative stress and metabolic disorders
Retinol saturase (RETSAT) uses oxygen as an acceptor and influences lipid metabolism and cellular stress responses; its dysregulation has been implicated in metabolic disorders and cancer. The oxidative nature of GO:0016727 reactions can contribute to reactive oxygen species production, linking these enzymes to oxidative stress pathologies.
Neurodegeneration and neurotransmitter synthesis
Dopamine beta-hydroxylase, a CH2-oxidizing enzyme, is required for norepinephrine synthesis; impaired activity is associated with autonomic dysfunction and neurodegenerative conditions. Other molybdenum-cofactor enzymes with GO:0016727 activity are involved in sulfur and purine metabolism, defects of which cause neurological symptoms.
Plant and microbial biotechnology
Protochlorophyllide oxidoreductase is essential for chlorophyll biosynthesis, and its manipulation affects photosynthetic efficiency. Eugenol biosynthesis in aspen involves oxidative enzymes acting on CH2 groups, highlighting biotechnological applications.
From oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of XDH affect uric acid levels? | Xdh knockout mouse or HepG2 knockout cells |
| How does RETSAT point mutation alter lipid metabolism? | RETSAT point-mutation knock-in HEK293 cells |
| Can tagged XDH reveal subcellular localization? | XDH knock-in with FLAG/GFP tag |
| Does overexpression of POR enhance photosynthesis? | POR overexpression in Arabidopsis or tobacco |
| Which genes are essential for CH2 oxidation? | Genome-wide CRISPR knockout library screening |
| Does RETSAT regulate autophagy in muscle? | Retsat knockout C2C12 myotubes |
How to Study the oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Oxygen consumption assay | O2 depletion by CH2 oxidation | Enzyme kinetics of XDH, RETSAT |
| H2O2 detection | Hydrogen peroxide production | Flavoenzyme activity |
| RNA-seq | Transcript levels of GO:0016727 genes | Disease vs. normal tissues |
| Proteomics | Protein abundance and modifications | Cofactor-dependent regulation |
| Metabolomics | Substrate and product levels | Purine and lipid metabolism |
| CRISPR knockout screen | Gene essentiality for CH2 oxidation | Pathway discovery |
| CRISPR knock-in | Tagged enzyme localization | Live-cell imaging |
| Enzyme-linked immunosorbent assay | Uric acid or retinol derivatives | Clinical biomarker studies |
Enzymatic activity assays
Direct measurement of GO:0016727 activity uses oxygen consumption or hydrogen peroxide production assays with specific substrates such as xanthine or retinol. These assays are typically performed with purified recombinant enzymes or cell lysates.
CRISPR-based genetic screens
Genome-wide CRISPR knockout libraries can identify genes required for CH2 oxidation pathways, as demonstrated in metabolic and stress-response studies. Hits are validated by targeted knockout and phenotypic assays.
Transcriptomics and proteomics
RNA-seq and quantitative proteomics reveal expression changes in GO:0016727 genes under disease or stress conditions. These methods help identify regulatory networks involving XDH, RETSAT, and PAOX.
Metabolomics and flux analysis
Metabolomic profiling of purine, lipid, and polyamine metabolites quantifies the impact of GO:0016727 activity on cellular metabolism. Stable isotope tracing can measure flux through these pathways.
How CRISPR Can Be Used to Study GO:0016727 oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor
Knockout
CRISPR knockout of genes encoding GO:0016727 enzymes, such as XDH or RETSAT, abolishes CH2 oxidation activity and reveals loss-of-function phenotypes in cell models. Knockout studies in mice have confirmed roles in purine catabolism and lipid metabolism.
Point Mutation
Point mutations in catalytic residues or cofactor-binding sites of GO:0016727 enzymes can dissect the contribution of specific amino acids to CH2 oxidation. For example, mutating the molybdenum-cofactor-binding cysteine in XDH abolishes activity.
Knock-in
Knock-in of epitope tags (e.g., FLAG, GFP) into endogenous loci allows visualization and immunoprecipitation of GO:0016727 enzymes under native regulation. This approach is valuable for studying subcellular localization and protein interactions.
Overexpression
Overexpression of GO:0016727 genes in cell lines or transgenic organisms can enhance metabolic flux through CH2 oxidation pathways, as shown for eugenol biosynthesis in aspen. Overexpression models are useful for gain-of-function studies and biotechnological applications.
How EDITGENE Supports oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor Research
Researchers studying oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor-related genes often need to determine whether a candidate gene is causally involved in a specific metabolic or disease phenotype. EDITGENE provides end-to-end CRISPR services to generate precisely engineered cell models for such investigations.
Contact EDITGENE today to design your custom CRISPR model for oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor research.
Frequently Asked Questions About oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor
What is GO:0016727?
GO:0016727 is a Gene Ontology molecular function term for oxidoreductase activity that acts on CH or CH2 groups using oxygen as the electron acceptor.
What genes are involved in oxidoreductase activity, acting on CH or CH2 groups, oxygen as acceptor?
Key genes include XDH, RETSAT, POR, PAOX, SMOX, DBH, and various cytochrome P450 and flavin-containing monooxygenases.
What diseases are linked to GO:0016727?
Diseases include gout and hyperuricemia (XDH), metabolic disorders (RETSAT), and neurodegeneration (DBH).
How is GO:0016727 activity measured?
It is measured by oxygen consumption, hydrogen peroxide production, or substrate conversion assays using purified enzymes or cell lysates.
What cofactors are required for GO:0016727?
Common cofactors include molybdenum cofactor, FAD, iron-sulfur clusters, and heme.
Can CRISPR be used to study GO:0016727?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to dissect the function of these enzymes.
What is the role of xanthine oxidoreductase in GO:0016727?
Xanthine oxidoreductase catalyzes the oxidation of xanthine to uric acid using oxygen as an acceptor, a classic example of GO:0016727 activity.
How does retinol saturase relate to GO:0016727?
Retinol saturase uses oxygen to saturate retinol, acting on a CH2 group, and is involved in lipid metabolism and stress responses.
Is protochlorophyllide oxidoreductase a GO:0016727 enzyme?
Yes, light-dependent protochlorophyllide oxidoreductase catalyzes a CH2 reduction using oxygen as an acceptor in chlorophyll biosynthesis.
What research methods are used for GO:0016727?
Methods include enzymatic assays, RNA-seq, proteomics, metabolomics, and CRISPR screens.
Conclusion
GO:0016727 defines a vital class of oxidoreductases that activate molecular oxygen to oxidize CH2 groups, impacting purine catabolism, lipid metabolism, chlorophyll biosynthesis, and drug detoxification. Understanding these enzymes through CRISPR-based models and multi-omics approaches can reveal new therapeutic targets for metabolic and oxidative stress-related diseases. EDITGENE offers comprehensive services to accelerate research on GO:0016727 and its associated genes.
References
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- 2. Weber P et al.. 2020. Retinol Saturase: More than the Name Suggests.. Trends Pharmacol Sci 41(6):418-427 PMID: 32345479
- 3. Kisker C et al.. 1997. Molybdenum-cofactor-containing enzymes: structure and mechanism.. Annu Rev Biochem 66:233-67 PMID: 9242907
- 4. Romero E et al.. 2014. Alcohol oxidation by flavoenzymes.. Biomol Concepts 5(4):299-318 PMID: 25372761
- 5. Layer G et al.. 2017. Reduction of Chemically Stable Multibonds: Nitrogenase-Like Biosynthesis of Tetrapyrroles.. Adv Exp Med Biol 925:147-161 PMID: 27957709
- 6. Koeduka T et al.. 2013. Enhancement of production of eugenol and its glycosides in transgenic aspen plants via genetic engineering.. Biochem Biophys Res Commun 436(1):73-8 PMID: 23707945
- 7. Attili L et al.. 2026. Polyamines and autophagy as a dynamic regulatory network in skeletal muscle regeneration and aging.. Mech Ageing Dev 231:112188 PMID: 42086115
- 8. Gabruk M et al.. 2015. Light-Dependent Protochlorophyllide Oxidoreductase: Phylogeny, Regulation, and Catalytic Properties.. Biochemistry 54(34):5255-62 PMID: 26230427
