GO:0042840 D-glucuronate catabolic process: Pathway Steps, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0042840 D-glucuronate catabolic process describes the chemical reactions and pathways that break down D-glucuronate, the D-enantiomer of glucuronate, into downstream metabolites.
• In fungi, a complete D-glucuronate catabolic pathway has been resolved, including an NADPH-dependent 5-keto-D-gluconate reductase and an L-idonate-forming 2-keto-L-gulonate reductase.
• In mammals, D-glucuronate is generated from myo-inositol by myo-inositol oxygenase and can be reduced by D-glucuronate reductase, linking this pathway to glucuronate metabolism and vitamin C-related flux.
• The pathway intersects with redox cofactor handling, since NADPH-dependent reductase steps are central to fungal D-glucuronate catabolism.
• D-glucuronate and its catabolic intermediates are relevant to metabolic phenotyping in human disease, including inflammation-associated mitochondrial dysfunction in acute-on-chronic liver failure.
• CRISPR-based knockout, point-mutation, knock-in, and overexpression models enable causal testing of candidate genes in the D-glucuronate catabolic process.
Description
GO:0042840 D-glucuronate catabolic process is a biological process ontology term that covers the chemical reactions and pathways resulting in the breakdown of D-glucuronate, the D-enantiomer of glucuronate. D-glucuronate is a uronic acid that can be generated from myo-inositol by myo-inositol oxygenase and can be further metabolized by reductases and related enzymes. Understanding this catabolic process is important because it sits at the intersection of carbohydrate metabolism, redox cofactor balance, and organism-specific pathways such as the fungal D-glucuronate degradation route. In mammalian systems, D-glucuronate metabolism is connected to vitamin C biosynthesis, recycling, and degradation, making the pathway relevant to redox biology and metabolic disease research. In clinical metabolomics, D-glucuronate-related metabolites have been associated with inflammation-associated mitochondrial dysfunction in acute-on-chronic liver failure, highlighting the translational value of this pathway. For researchers, GO:0042840 provides a precise annotation framework for assigning gene function, interpreting metabolomic data, and designing CRISPR-based experiments that test whether candidate enzymes are causally required for D-glucuronate breakdown.
D-glucuronate catabolic process At A Glance
| GO ID | GO:0042840 |
|---|---|
| GO term | D-glucuronate catabolic process |
| Ontology | biological_process |
| Synonym | D-glucuronate breakdown; D-glucuronate catabolism; D-glucuronate degradation |
| Major function | Breakdown of D-glucuronate into downstream metabolites through enzymatic catabolic steps |
| Representative enzymes | NADPH-dependent 5-keto-D-gluconate reductase; L-idonate-forming 2-keto-L-gulonate reductase; D-glucuronate reductase; myo-inositol oxygenase |
| Organism examples | Fungal D-glucuronate catabolism and mammalian glucuronate-related metabolism |
| Related cofactors | NADPH is required for a key fungal reductase step in D-glucuronate catabolism |
| Research relevance | Metabolic pathway annotation, metabolomics interpretation, and CRISPR functional validation |
What Is GO:0042840?
GO:0042840 D-glucuronate catabolic process is defined as the chemical reactions and pathways resulting in the breakdown of D-glucuronate, the D-enantiomer of glucuronate. In practical terms, it includes the enzymatic steps that convert D-glucuronate into downstream metabolites, such as reductase-mediated conversions and subsequent catabolic reactions. The term is a biological process annotation and is used to describe gene products and pathways that degrade D-glucuronate rather than synthesize it.
Why Is D-glucuronate catabolic process Important in Cell Biology?
GO:0042840 is important because it provides a standardized way to annotate and investigate the degradation of D-glucuronate, a metabolite that connects carbohydrate metabolism, redox cofactor handling, and organism-specific catabolic routes. In fungi, the pathway has been experimentally resolved into distinct reductase steps, making it a tractable model for enzyme discovery and pathway reconstruction. In mammals, D-glucuronate metabolism intersects with myo-inositol oxygenase and D-glucuronate reductase reactions that are relevant to vitamin C-related pathways and redox biology. Clinically, D-glucuronate-related metabolic signatures have been linked to inflammation-associated mitochondrial dysfunction in acute-on-chronic liver failure, supporting the pathway as a candidate axis for biomarker and mechanism studies.
• Provides a precise GO annotation for genes and pathways that degrade D-glucuronate.
• Connects D-glucuronate catabolism to NADPH-dependent redox reactions in fungi.
• Links myo-inositol oxygenase and D-glucuronate reductase to mammalian glucuronate metabolism.
• Supports interpretation of vitamin C biosynthesis, recycling, and degradation pathways in mammals.
• Enables metabolomic studies of D-glucuronate-related metabolites in human disease.
• Provides a framework for comparative pathway analysis between fungal and mammalian systems.
• Supports CRISPR knockout and knock-in experiments to test causal roles of candidate enzymes.
• Helps annotate uncharacterized reductases and dehydrogenases in metabolic networks.
• Can guide microbial engineering and metabolic modeling of uronic acid utilization.
• Offers a testable pathway for linking gut-brain and butyrate-related metabolic modulation to systemic metabolism.
What Happens During D-glucuronate catabolic process?
Entry of D-glucuronate into the catabolic pathway
In simple terms: D-glucuronate first has to be made available or delivered to the enzymes that will break it down.
The D-glucuronate catabolic process begins with D-glucuronate as the substrate. In mammals, D-glucuronate can be produced from myo-inositol by myo-inositol oxygenase, and the resulting D-glucuronate can be transferred to D-glucuronate reductase, linking substrate generation to downstream catabolic handling. In fungi, D-glucuronate is the entry metabolite for a dedicated catabolic pathway that has been resolved into specific enzymatic steps.
Reductase-mediated conversion steps
In simple terms: Enzymes called reductases chemically modify D-glucuronate and its derivatives so they can be further broken down.
A central feature of fungal D-glucuronate catabolism is the action of reductases. An NADPH-dependent 5-keto-D-gluconate reductase is part of the fungal pathway for D-glucuronate catabolism, indicating that reduced cofactor supply is required for this route. A separate study identified a novel fungal D-glucuronate catabolic pathway containing an L-idonate-forming 2-keto-L-gulonate reductase, showing that multiple reductase-dependent branches can contribute to D-glucuronate breakdown.
Formation of downstream intermediates
In simple terms: The modified sugars are converted into intermediate molecules that feed into later catabolic steps.
The fungal pathway generates specific intermediates such as L-idonate through the action of 2-keto-L-gulonate reductase, demonstrating that D-glucuronate catabolism proceeds through defined metabolite intermediates rather than a single reaction. The NADPH-dependent 5-keto-D-gluconate reductase step further supports a multi-step route in which D-glucuronate-derived compounds are sequentially converted.
Connection to redox and cofactor metabolism
In simple terms: Breaking down D-glucuronate is tied to the cell's redox balance because some steps need NADPH.
Because the fungal 5-keto-D-gluconate reductase is NADPH-dependent, D-glucuronate catabolism is coupled to cellular redox and cofactor metabolism. In mammals, D-glucuronate reductase activity and myo-inositol oxygenase-mediated D-glucuronate transfer connect this pathway to broader glucuronate and vitamin C-related metabolic networks.
Physiological and disease-associated context
In simple terms: Changes in D-glucuronate-related metabolism can be detected in human disease states.
Blood metabolomics has uncovered inflammation-associated mitochondrial dysfunction as a potential mechanism underlying acute-on-chronic liver failure, with D-glucuronate-related metabolic signals contributing to the observed metabolic phenotype. This places GO:0042840 within a translational context where catabolic flux and intermediate abundance may reflect disease-associated metabolic stress.
Key Genes Involved in GO:0042840 D-glucuronate catabolic process
The following genes and enzymes have been experimentally linked to D-glucuronate catabolism or closely related D-glucuronate metabolic steps.
| Gene | Major Role | Research Relevance |
|---|---|---|
| 5-keto-D-gluconate reductase (NADPH-dependent) | Reductase step in fungal D-glucuronate catabolism | Enzyme discovery and pathway reconstruction in fungi |
| 2-keto-L-gulonate reductase | L-idonate-forming step in a novel fungal D-glucuronate catabolic pathway | Defines an alternative fungal route for D-glucuronate breakdown |
| D-glucuronate reductase | Reduction of D-glucuronate | Mechanistic studies of D-glucuronate transfer and reduction |
| Myo-inositol oxygenase | Generates D-glucuronate from myo-inositol | Links inositol metabolism to D-glucuronate catabolic flux |
| AKR1A (aldehyde reductase) | Pleiotropic reductase with metabolic roles | Provides context for reductase families relevant to uronic acid metabolism |
| β-glucuronidase-related enzymes | Glucuronide processing and glucuronate release | Connects glucuronate metabolism to glycosylation and drug metabolism |
| Methyl 1,2,3,4-tetra-O-acetyl-β-D-glucuronate-related glycosyl donors | Model substrate for β-glucuronidation studies | Chemical biology tool for studying glucuronate transfer |
| Butyrate metabolism-associated genes | Gut-brain axis and systemic metabolic modulation | Context for metabolite-driven metabolic remodeling |
| Mitochondrial dysfunction-associated metabolic genes | Inflammation-associated metabolic stress | Links D-glucuronate-related metabolomics to ACLF |
| Vitamin C pathway genes | Biosynthesis, recycling, and degradation of vitamin C | Connects mammalian glucuronate metabolism to redox biology |
| NADPH-generating enzymes | Supply reducing equivalents for reductase steps | Supports NADPH-dependent D-glucuronate catabolic reactions |
| Fungal uronic acid utilization genes | Uptake and catabolism of uronic acids | Model system for D-glucuronate catabolism |
| L-idonate-related metabolic genes | Downstream intermediate handling | Defines branch points in fungal D-glucuronate catabolism |
| 5-keto-D-gluconate-related genes | Intermediate formation and conversion | Supports stepwise pathway models |
| Glucuronidation enzymes | Transfer of glucuronate moieties | Relevant to D-glucuronate donor chemistry |
| Redox stress response genes | Cellular response to metabolic redox imbalance | Connects D-glucuronate catabolism to mitochondrial dysfunction |
How Is D-glucuronate catabolic process Regulated?
D-glucuronate catabolic process is regulated at the level of enzyme availability and cofactor supply. The NADPH-dependent 5-keto-D-gluconate reductase step indicates that the pathway is sensitive to cellular NADPH status, linking its regulation to redox metabolism. In mammals, the transfer of D-glucuronate from myo-inositol oxygenase to D-glucuronate reductase suggests that substrate channeling or enzyme-to-enzyme interaction may influence flux through D-glucuronate-handling reactions. In addition, vitamin C biosynthesis, recycling, and degradation pathways provide a broader metabolic context in which glucuronate-related flux can be modulated. Disease-associated metabolic stress, such as inflammation-associated mitochondrial dysfunction in acute-on-chronic liver failure, may also alter the abundance of D-glucuronate-related metabolites and thereby reflect pathway activity.
D-glucuronate catabolic process and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| D-glucuronate reductase | Redox and glucuronate metabolism | Knockout and point-mutation cell models |
| Myo-inositol oxygenase | Inositol-linked D-glucuronate generation | Overexpression and tagged knock-in models |
| 5-keto-D-gluconate reductase | Fungal D-glucuronate catabolism | Fungal knockout and complementation models |
| 2-keto-L-gulonate reductase | Fungal alternative D-glucuronate pathway | Knockout and knock-in fungal models |
| Mitochondrial dysfunction-associated genes | Acute-on-chronic liver failure | Metabolomics-coupled knockout models |
Acute-on-chronic liver failure and inflammation-associated mitochondrial dysfunction
Blood metabolomics has uncovered inflammation-associated mitochondrial dysfunction as a potential mechanism underlying acute-on-chronic liver failure, with D-glucuronate-related metabolic signals contributing to the metabolic phenotype. This suggests that D-glucuronate catabolic process and related metabolites may serve as candidate biomarkers or mechanistic readouts in liver failure research.
Redox and vitamin C-related metabolic disorders
Mammalian D-glucuronate metabolism intersects with vitamin C biosynthesis, recycling, and degradation, processes that are central to redox homeostasis. D-glucuronate reductase and myo-inositol oxygenase-mediated D-glucuronate transfer further connect this pathway to redox-related metabolic functions.
Gut-brain axis and metabolic modulation
Sodium oligomannate modulates the gut-brain axis to alleviate post-stroke cognitive impairment by restoring butyrate metabolism, illustrating how microbial and systemic metabolic pathways can influence neurological outcomes. Although this study focuses on butyrate, it provides a framework for investigating how related carbohydrate and uronic acid catabolic pathways, including D-glucuronate catabolism, may participate in gut-brain metabolic signaling.
Fungal pathogenesis and metabolic adaptation
Fungal D-glucuronate catabolism has been resolved into specific enzymatic steps, including an NADPH-dependent 5-keto-D-gluconate reductase and an L-idonate-forming 2-keto-L-gulonate reductase. Understanding these fungal pathways is relevant to fungal metabolic adaptation and may inform studies of fungal survival in host environments.
From D-glucuronate catabolic process-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is a candidate reductase required for D-glucuronate catabolism? | CRISPR knockout cell model |
| Does a specific amino acid substitution alter reductase activity? | CRISPR point-mutation knock-in |
| Can a tagged enzyme be used to track pathway localization? | Tagged knock-in |
| Does overexpression increase D-glucuronate catabolic flux? | CRISPR overexpression model |
| Which genes are essential for fungal D-glucuronate catabolism? | CRISPR library screening in fungal cells |
| How does D-glucuronate catabolism change in disease-associated metabolic stress? | Metabolomics with knockout and overexpression models |
How to Study the D-glucuronate catabolic process Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Metabolomics | Abundance of D-glucuronate and related metabolites | Disease biomarker discovery and pathway activity |
| Stable-isotope tracing | Flux through catabolic intermediates | Pathway reconstruction |
| Recombinant enzyme assay | Reductase activity and cofactor dependence | Functional annotation of candidate genes |
| CRISPR knockout | Loss-of-function effect on D-glucuronate catabolism | Causal gene testing |
| CRISPR point mutation | Effect of specific amino acid changes on enzyme function | Mechanistic enzymology |
| Tagged knock-in | Protein localization and interaction | Pathway compartmentalization studies |
| Overexpression | Gain-of-function effect on catabolic flux | Pathway activation studies |
| CRISPR library screening | Genome-wide requirement for D-glucuronate catabolism | Discovery of novel pathway genes |
Metabolomics and flux analysis
Metabolomics can quantify D-glucuronate and its downstream intermediates to assess pathway activity. Blood metabolomics has been used to uncover inflammation-associated mitochondrial dysfunction in acute-on-chronic liver failure, demonstrating how D-glucuronate-related metabolites can be detected in clinical samples. Stable-isotope tracing can further resolve flux through reductase-dependent steps.
Enzyme activity assays
Recombinant enzyme assays are used to measure reductase activities, such as NADPH-dependent 5-keto-D-gluconate reductase and L-idonate-forming 2-keto-L-gulonate reductase, which are directly implicated in fungal D-glucuronate catabolism. These assays help assign specific enzymatic functions to candidate genes.
Genetic and CRISPR screens
CRISPR knockout and library screening approaches can identify genes required for D-glucuronate catabolism. By disrupting candidate reductases and related metabolic genes, researchers can test whether loss of function blocks D-glucuronate breakdown.
Comparative genomics and pathway reconstruction
Comparative analysis of fungal and mammalian pathways can reveal conserved and divergent steps in D-glucuronate catabolism. The fungal pathway containing an L-idonate-forming 2-keto-L-gulonate reductase provides a clear example of a non-canonical route that can be compared with mammalian glucuronate metabolism.
How CRISPR Can Be Used to Study GO:0042840 D-glucuronate catabolic process
Knockout
CRISPR knockout can be used to delete candidate genes such as D-glucuronate reductase or fungal 5-keto-D-gluconate reductase to test whether they are required for D-glucuronate catabolism. Loss-of-function models combined with metabolomics can reveal pathway blocks and accumulated intermediates.
Point Mutation
CRISPR point mutation enables precise substitution of catalytic residues in reductases, allowing researchers to dissect mechanism without deleting the entire gene. This is particularly useful for NADPH-dependent enzymes where cofactor binding and catalysis can be separated.
Knock-in
Knock-in of tags or reporter sequences can be used to track the localization and dynamics of D-glucuronate catabolic enzymes. Tagged knock-in models are valuable for studying enzyme trafficking and interaction with myo-inositol oxygenase or D-glucuronate reductase.
Overexpression
CRISPR overexpression can increase the abundance of rate-limiting enzymes to test whether D-glucuronate catabolic flux is enhanced. This approach can be combined with metabolomics to quantify changes in D-glucuronate and downstream intermediates.
How EDITGENE Supports D-glucuronate catabolic process Research
Researchers studying D-glucuronate catabolic process-related genes often need to determine whether a candidate gene is causally involved in D-glucuronate breakdown or whether it merely correlates with pathway activity. EDITGENE provides CRISPR-based cell model services that enable knockout, point-mutation, knock-in, overexpression, and library screening experiments tailored to metabolic pathway research.
Contact EDITGENE today to design your custom CRISPR model for D-glucuronate catabolic process research.
Frequently Asked Questions About D-glucuronate catabolic process
What is GO:0042840 D-glucuronate catabolic process?
GO:0042840 is a biological process ontology term describing the chemical reactions and pathways that break down D-glucuronate, the D-enantiomer of glucuronate.
What genes are involved in D-glucuronate catabolic process?
Genes encoding D-glucuronate reductase, myo-inositol oxygenase, NADPH-dependent 5-keto-D-gluconate reductase, and L-idonate-forming 2-keto-L-gulonate reductase have been linked to D-glucuronate metabolism and catabolism.
Why is D-glucuronate catabolism important?
It connects carbohydrate metabolism, redox cofactor handling, and disease-associated metabolic phenotypes such as inflammation-associated mitochondrial dysfunction in acute-on-chronic liver failure.
Is D-glucuronate catabolism conserved between fungi and mammals?
Fungal D-glucuronate catabolism has been resolved into specific reductase steps, while mammalian D-glucuronate metabolism intersects with myo-inositol oxygenase and D-glucuronate reductase, indicating both shared and organism-specific features.
What cofactors are required for D-glucuronate catabolism?
NADPH is required for the NADPH-dependent 5-keto-D-gluconate reductase step in fungal D-glucuronate catabolism.
How can CRISPR be used to study D-glucuronate catabolic process?
CRISPR knockout, point mutation, knock-in, overexpression, and library screening can be used to test whether candidate genes are required for or sufficient to drive D-glucuronate breakdown.
What diseases are associated with D-glucuronate metabolism?
D-glucuronate-related metabolic signals have been associated with acute-on-chronic liver failure and inflammation-associated mitochondrial dysfunction.
What methods are used to study D-glucuronate catabolism?
Metabolomics, stable-isotope tracing, recombinant enzyme assays, and CRISPR-based genetic screens are commonly used to study this pathway.
What is the role of myo-inositol oxygenase in D-glucuronate metabolism?
Myo-inositol oxygenase generates D-glucuronate from myo-inositol and can transfer D-glucuronate to D-glucuronate reductase, linking inositol metabolism to D-glucuronate catabolic flux.
How does D-glucuronate catabolism relate to vitamin C metabolism?
In mammals, D-glucuronate metabolism is connected to vitamin C biosynthesis, recycling, and degradation pathways, which are important for redox homeostasis.
Conclusion
GO:0042840 D-glucuronate catabolic process provides a precise annotation for the enzymatic breakdown of D-glucuronate, a metabolite that links carbohydrate metabolism, redox cofactor handling, and disease-associated metabolic phenotypes. Experimental studies in fungi have resolved specific reductase-dependent steps, while mammalian studies connect D-glucuronate metabolism to myo-inositol oxygenase, D-glucuronate reductase, and vitamin C-related pathways. Clinically, D-glucuronate-related metabolic signals have been observed in acute-on-chronic liver failure, supporting the pathway as a candidate axis for biomarker and mechanism research. CRISPR-based knockout, point-mutation, knock-in, overexpression, and library screening models offer a direct route to test causal gene function in this pathway.
References
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- 5. Kajimoto T et al.. 2024. Effect of 1,4-Dioxane Solvent on β-Glucuronidation Using Methyl 1,2,3,4-Tetra-O-acetyl-β-D-glucuronate as the Glycosyl Donor.. Chem Pharm Bull (Tokyo) 72(4):408-412 PMID: 38658365
- 6. Naber NI et al.. 1987. Concerning the mechanism for transfer of D-glucuronate from myo-inositol oxygenase to D-glucuronate reductase.. Biochim Biophys Acta 911(3):365-8 PMID: 3814609
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