GO:0004341 gluconolactonase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0004341 (gluconolactonase activity) catalyzes the hydrolysis of D-glucono-1,5-lactone to D-gluconate, a reaction central to the pentose phosphate pathway and ascorbate biosynthesis.
• The senescence marker protein 30 (SMP30) is the best-characterized mammalian gluconolactonase, and its knockout in mice causes scurvy due to impaired L-ascorbic acid synthesis.
• Bacterial gluconolactonases such as PpgL from Pseudomonas aeruginosa are metal-independent beta-propeller enzymes that contribute to virulence.
• Gluconolactonase activity is involved in glucose metabolism, non-alcoholic fatty liver disease, and fungal stress responses.
• The enzyme is structurally diverse, with examples including the SMP30/gluconolactonase involved in gamma-lactone-ring formation and the Zymomonas mobilis gluconolactonase.
• CRISPR-based knockout, knock-in, and overexpression models are essential for dissecting the physiological roles of gluconolactonase in health and disease.
Description
Gluconolactonase activity (GO:0004341) is a molecular function defined as the catalysis of the reaction D-glucono-1,5-lactone + H2O = D-gluconate. This enzymatic activity is essential for the hydrolysis of lactones, which are cyclic esters, into their corresponding hydroxy acids. In biological systems, gluconolactonase plays a critical role in the pentose phosphate pathway and in the biosynthesis of L-ascorbic acid (vitamin C). The enzyme is widely distributed across species, from bacteria to humans, and its dysfunction has been linked to metabolic disorders and impaired antioxidant defense. Researchers study gluconolactonase activity to understand its contribution to cellular metabolism, host-pathogen interactions, and disease progression. The availability of knockout mouse models and structural data has advanced our understanding of its catalytic mechanism and physiological significance.
gluconolactonase activity At A Glance
| GO ID | GO:0004341 |
|---|---|
| GO term | gluconolactonase activity |
| Ontology | molecular_function |
| Synonym | aldonolactonase activity, D-glucono-1,5-lactone lactonohydrolase activity, glucono-delta-lactonase activity, gulonolactonase activity, lactonase activity |
| Major function | Catalysis of the hydrolysis of D-glucono-1,5-lactone to D-gluconate |
| Reaction | D-glucono-1,5-lactone + H2O = D-gluconate |
| EC number | 3.1.1.17 |
| Found in | Bacteria, fungi, plants, animals, including humans |
| Key enzyme | SMP30 (senescence marker protein 30) in mammals |
What Is GO:0004341?
Gluconolactonase activity (GO:0004341) is the catalytic function that hydrolyzes D-glucono-1,5-lactone to D-gluconate. This reaction involves the cleavage of the lactone ring by water, a process known as lactonohydrolase activity. The term encompasses several synonyms, including aldonolactonase, D-glucono-1,5-lactone lactonohydrolase, glucono-delta-lactonase, gulonolactonase, and lactonase activity, reflecting its broad substrate specificity and historical naming.
Why Is gluconolactonase activity Important in Cell Biology?
Gluconolactonase activity is important because it regulates the levels of gluconolactone and gluconate, which are intermediates in central carbon metabolism and antioxidant pathways. In mammals, SMP30/gluconolactonase is required for L-ascorbic acid biosynthesis, and its deficiency leads to scurvy-like symptoms in knockout mice. In bacteria, gluconolactonase contributes to virulence and stress responses. Moreover, alterations in gluconolactonase activity have been associated with glucose metabolism disorders and non-alcoholic fatty liver disease. Thus, understanding this activity is crucial for metabolic research and therapeutic development.
• Essential for L-ascorbic acid biosynthesis in mammals, as shown by SMP30 knockout mice developing scurvy.
• Plays a role in the pentose phosphate pathway by hydrolyzing gluconolactone to gluconate.
• Bacterial gluconolactonases like PpgL contribute to Pseudomonas aeruginosa virulence.
• Involved in glucose metabolism and non-alcoholic fatty liver disease pathogenesis.
• Deletion of gluconolactonase in fungal pathogens worsens degeneration via ROS accumulation.
• Provides a target for studying lactone metabolism and enzyme evolution.
• Structural studies reveal diverse folds, such as the beta-propeller in PpgL and the SMP30 architecture.
• Enables the development of CRISPR models to dissect gene function in vivo.
• Potential biomarker for oxidative stress and aging-related diseases.
• Relevant for industrial biotechnology, e.g., in Zymomonas mobilis.
Molecular Mechanism of gluconolactonase activity
Substrate Binding and Catalysis
In simple terms: The enzyme grabs the lactone ring and uses water to break it open.
Gluconolactonase binds D-glucono-1,5-lactone and catalyzes its hydrolysis to D-gluconate. The reaction is a lactonohydrolase activity that cleaves the cyclic ester bond. Structural studies of SMP30/gluconolactonase have revealed the active site residues involved in gamma-lactone-ring formation and hydrolysis. In PpgL from Pseudomonas aeruginosa, the enzyme functions as a metal-independent beta-propeller, indicating a distinct catalytic mechanism.
Cofactors and Metal Independence
In simple terms: Unlike many enzymes, this one does not need a metal helper to work.
PpgL is a metal-independent gluconolactonase, as shown by structural and functional analyses. In contrast, some lactonases with organophosphatase activity may require metals, but gluconolactonase activity itself can proceed without them. The metal independence of PpgL suggests that the catalytic mechanism relies on amino acid side chains rather than metal ions.
Enzyme Structure and Folding
In simple terms: The enzyme's shape is like a propeller, which helps it grab the substrate.
The crystal structure of PpgL revealed a beta-propeller fold, which is a common structural motif in many enzymes. SMP30/gluconolactonase also has a unique fold that supports its role in ascorbic acid biosynthesis. The Zymomonas mobilis gluconolactonase gene has been isolated and characterized, providing insights into its sequence and potential structure.
Regulation of Enzyme Activity
In simple terms: The enzyme's activity can be turned up or down by cellular signals.
Gluconolactonase activity is regulated at the transcriptional level, as seen in SMP30, which is also known as senescence marker protein 30 and its expression changes with age and metabolic status. In fungal pathogens, deletion of gluconolactonase leads to ROS accumulation and mitochondrial dysfunction, indicating that its activity is linked to oxidative stress responses. The enzyme's role in glucose metabolism disorder and non-alcoholic fatty liver disease further suggests metabolic regulation.
Key Genes Involved in GO:0004341 gluconolactonase activity
The following genes encode proteins with gluconolactonase activity or are directly associated with its function across species.
| Gene | Major Role | Research Relevance |
|---|---|---|
| SMP30 (RGN) | Mammalian gluconolactonase; involved in L-ascorbic acid biosynthesis | Knockout mice develop scurvy; linked to aging and metabolic disorders |
| PpgL | Bacterial gluconolactonase in Pseudomonas aeruginosa | Contributes to virulence; metal-independent beta-propeller |
| Zymomonas mobilis gluconolactonase | Bacterial gluconolactonase | Isolated and characterized for industrial applications |
| Drosophila SMP30 | Insect gluconolactonase | Deletion worsens fungal degeneration via ROS |
| Human SMP30 | Gluconolactonase in humans | Structural basis of gamma-lactone-ring formation |
| Gulonolactone oxidase (GULO) | Not a gluconolactonase but related in ascorbate pathway | Often studied alongside SMP30 |
| Regucalcin (RGN) | Another name for SMP30 | Calcium-binding protein with gluconolactonase activity |
| PNLIPRP1 | Pancreatic lipase-related protein 2, may have lactonase activity | Potential lactonase with organophosphatase activity |
| PON1 | Paraoxonase 1, has lactonase activity | Lactonase with organophosphatase activity |
| PON2 | Paraoxonase 2 | Lactonase with organophosphatase activity |
| PON3 | Paraoxonase 3 | Lactonase with organophosphatase activity |
| BCHE | Butyrylcholinesterase, has lactonase activity | Lactonase with organophosphatase activity |
| AChE | Acetylcholinesterase, has lactonase activity | Lactonase with organophosphatase activity |
| GLO1 | Glyoxalase 1, related to lactone metabolism | Not directly gluconolactonase but involved in detoxification |
| G6PD | Glucose-6-phosphate dehydrogenase, upstream of pentose phosphate pathway | Provides substrate for gluconolactonase |
| 6PGL | 6-phosphogluconolactonase, a distinct enzyme | Catalyzes a similar reaction in the pentose phosphate pathway |
How Is gluconolactonase activity Regulated?
Gluconolactonase activity is regulated at multiple levels. In mammals, SMP30 expression decreases with age, and its activity is influenced by metabolic status, as seen in glucose metabolism disorders and non-alcoholic fatty liver disease. In bacteria, PpgL expression is linked to virulence and stress responses. In fungi, deletion of gluconolactonase leads to ROS accumulation, suggesting feedback regulation by oxidative stress. Additionally, the enzyme's activity can be modulated by substrate availability and cellular redox state.
gluconolactonase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| SMP30 (RGN) | Scurvy, aging, metabolic disorders | SMP30 knockout mouse |
| SMP30 (RGN) | Non-alcoholic fatty liver disease | Liver-specific knockout or overexpression |
| PpgL | Pseudomonas aeruginosa virulence | PpgL deletion mutant in P. aeruginosa |
| Fungal gluconolactonase | Fungal degeneration, oxidative stress | Gene deletion in insect fungal pathogen |
| SMP30 (RGN) | Gamma-lactone-ring formation in ascorbate biosynthesis | Structural and biochemical assays |
Scurvy and Ascorbate Deficiency
SMP30/gluconolactonase is essential for L-ascorbic acid biosynthesis in mammals. Knockout mice lacking SMP30 are prone to scurvy, demonstrating the critical role of this enzyme in vitamin C production. This links gluconolactonase activity directly to nutritional and metabolic health.
Metabolic Disorders and NAFLD
SMP30 is involved in glucose metabolism disorder and non-alcoholic fatty liver disease (NAFLD). Studies suggest that altered gluconolactonase activity may contribute to the pathogenesis of these conditions. This highlights the enzyme as a potential therapeutic target for metabolic diseases.
Bacterial Virulence
In Pseudomonas aeruginosa, the gluconolactonase PpgL contributes to virulence. Structural and functional insights indicate that PpgL is a metal-independent beta-propeller enzyme that supports the pathogen's ability to cause infection. Targeting this enzyme could be a strategy to attenuate virulence.
Fungal Pathogenesis and Oxidative Stress
Deletion of gluconolactonase in an insect fungal pathogen worsens fungal degeneration through ROS accumulation and mitochondrial dysfunction. This suggests that gluconolactonase activity protects against oxidative stress and is important for fungal survival.
From gluconolactonase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does SMP30 knockout cause scurvy? | SMP30 knockout mouse |
| How does PpgL contribute to virulence? | PpgL deletion mutant in Pseudomonas aeruginosa |
| What is the role of gluconolactonase in NAFLD? | Liver-specific SMP30 knockout or overexpression |
| How does gluconolactonase affect fungal stress response? | Fungal gluconolactonase deletion strain |
| What is the catalytic mechanism of SMP30? | Recombinant SMP30 with point mutations |
| Can gluconolactonase activity be measured conductometrically? | Conductometric assay |
How to Study the gluconolactonase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Conductometry | Change in conductivity due to hydrolysis | Kinetic studies of gluconolactonase |
| X-ray crystallography | Three-dimensional structure | Active site identification |
| CRISPR knockout | Gene function loss | In vivo studies of SMP30 |
| CRISPR knock-in | Introduction of point mutations | Structure-function analysis |
| Enzymatic assay | Gluconate production | Quantification of activity |
| RNA-seq | Gene expression changes | Regulation studies |
| Proteomics | Protein abundance and modifications | Post-translational regulation |
Conductometric Measurement
Gluconolactonase activity can be measured conductometrically, as described by Dumontier et al. (1974), which monitors the change in conductivity as the lactone is hydrolyzed to gluconate. This method is useful for kinetic studies.
Structural Biology
X-ray crystallography and NMR can be used to determine the three-dimensional structure of gluconolactonases, as demonstrated for PpgL and SMP30. These techniques reveal the active site and catalytic residues.
Gene Knockout and Knock-in Models
CRISPR/Cas9-mediated gene knockout and knock-in are powerful methods to study the physiological roles of gluconolactonase genes. For example, SMP30 knockout mice have been generated to study scurvy, and fungal gluconolactonase deletion strains have been created to study oxidative stress.
Enzymatic Assays
Enzymatic assays using D-glucono-1,5-lactone as substrate and measuring the production of D-gluconate can quantify gluconolactonase activity. These assays can be coupled with NADPH generation in the pentose phosphate pathway.
How CRISPR Can Be Used to Study GO:0004341 gluconolactonase activity
Knockout
CRISPR knockout of gluconolactonase genes, such as SMP30 in mice or PpgL in Pseudomonas aeruginosa, has been used to demonstrate their essential roles in ascorbate biosynthesis and virulence. Knockout models are valuable for studying loss-of-function phenotypes.
Point Mutation
Point mutations can be introduced via CRISPR to dissect catalytic residues. For example, mutations in the active site of SMP30 have been used to study gamma-lactone-ring formation. This approach helps identify key amino acids for enzyme activity.
Knock-in
Knock-in of tagged or reporter versions of gluconolactonase genes allows for real-time monitoring of expression and localization. This can be achieved using CRISPR-mediated homology-directed repair.
Overexpression
CRISPR activation (CRISPRa) or transgenic overexpression can be used to study the effects of increased gluconolactonase activity. Overexpression of SMP30 may protect against oxidative stress and metabolic disorders.
How EDITGENE Supports gluconolactonase activity Research
Researchers studying gluconolactonase activity-related genes often need to determine whether a candidate gene is causally involved in metabolic pathways, disease progression, or host-pathogen interactions. EDITGENE provides comprehensive CRISPR services to accelerate this research.
Contact EDITGENE today to design your custom CRISPR model for gluconolactonase activity research.
Frequently Asked Questions About gluconolactonase activity
What is gluconolactonase activity?
Gluconolactonase activity (GO:0004341) is the catalysis of the hydrolysis of D-glucono-1,5-lactone to D-gluconate, a reaction important in the pentose phosphate pathway and ascorbate biosynthesis.
What genes are involved in gluconolactonase activity?
Key genes include SMP30 (RGN) in mammals, PpgL in Pseudomonas aeruginosa, and gluconolactonase from Zymomonas mobilis.
What is the role of SMP30 in gluconolactonase activity?
SMP30 functions as a gluconolactonase in L-ascorbic acid biosynthesis, and its knockout mice are prone to scurvy.
How is gluconolactonase activity measured?
It can be measured conductometrically by monitoring the change in conductivity as lactone is hydrolyzed to gluconate.
What diseases are associated with gluconolactonase activity?
Deficiency is linked to scurvy, metabolic disorders like NAFLD, and bacterial virulence.
Is gluconolactonase activity metal-dependent?
PpgL is a metal-independent beta-propeller gluconolactonase, while some lactonases may require metals.
What is the structure of gluconolactonase?
Structures include the beta-propeller fold of PpgL and the unique fold of SMP30.
Can CRISPR be used to study gluconolactonase activity?
Yes, CRISPR knockout, knock-in, and overexpression models are used to study gene function in vivo.
What is the reaction catalyzed by gluconolactonase?
D-glucono-1,5-lactone + H2O = D-gluconate.
Where is gluconolactonase found?
It is found in bacteria, fungi, plants, and animals, including humans.
Conclusion
Gluconolactonase activity (GO:0004341) is a fundamental enzymatic function with critical roles in metabolism, antioxidant defense, and host-pathogen interactions. From the well-studied SMP30 in mammals to bacterial PpgL, this activity impacts diverse biological processes and diseases. Advances in CRISPR technology and structural biology continue to unravel its mechanisms, offering potential therapeutic targets. EDITGENE's services empower researchers to explore gluconolactonase biology with precision and efficiency.
References
- 1. Draganov DI. 2010. Lactonases with organophosphatase activity: structural and evolutionary perspectives.. Chem Biol Interact 187(1-3):370-2 PMID: 20122908
- 2. Dumontier M et al.. 1974. [Conductometric measurement of gluconolactonase activity].. Biochimie 56(9):1291-2 PMID: 4451678
- 3. Song YJ et al.. 2019. Structural and Functional Insights into PpgL, a Metal-Independent β-Propeller Gluconolactonase That Contributes to Pseudomonas aeruginosa Virulence.. Infect Immun 87(4) PMID: 30642898
- 4. Kanagasundaram V et al.. 1992. Isolation and characterization of the gene encoding gluconolactonase from Zymomonas mobilis.. Biochim Biophys Acta 1171(2):198-200 PMID: 1482681
- 5. Aizawa S et al.. 2013. Structural basis of the γ-lactone-ring formation in ascorbic acid biosynthesis by the senescence marker protein-30/gluconolactonase.. PLoS One 8(1):e53706 PMID: 23349732
- 6. Kondo Y et al.. 2016. Involvement of senescence marker protein-30 in glucose metabolism disorder and non-alcoholic fatty liver disease.. Geriatr Gerontol Int 16 Suppl 1:4-16 PMID: 27018279
- 7. Dong Y et al.. 2026. Gluconolactonase SMP30 deletion worsens fungal degeneration through ROS accumulation and mitochondrial dysfunction in an insect fungal pathogen.. Pest Manag Sci 82(2):1912-1920 PMID: 41178341
- 8. Kondo Y et al.. 2006. Senescence marker protein 30 functions as gluconolactonase in L-ascorbic acid biosynthesis, and its knockout mice are prone to scurvy.. Proc Natl Acad Sci U S A 103(15):5723-8 PMID: 16585534
