GO:0050074 malate-CoA ligase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0050074 malate-CoA ligase activity catalyzes the ATP-dependent conversion of malate and CoA to malyl-CoA, ADP, and phosphate.
• The enzyme belongs to the ATP-dependent carboxylate-amine/thiol ligase superfamily, which includes succinyl-CoA synthetase and other CoA-ligases.
• Malate thiokinase, a synonym for this activity, exhibits half-of-the-sites reactivity and a random site reaction mechanism.
• In Methylobacterium extorquens AM1, malate-CoA ligase is part of the methanol assimilation pathway and is essential for growth on methanol.
• Some succinate-CoA ligases can also convert malate to malyl-CoA, indicating broader substrate specificity than previously recognized.
• The enzyme from Aureobasidium pullulans functions in the polymerization pathway of polymalic acid, a biodegradable polymer.
Description
Malate-CoA ligase activity (GO:0050074) is a molecular function that catalyzes the ATP-dependent ligation of malate and coenzyme A to form malyl-CoA, ADP, and phosphate. This reaction is central to several metabolic pathways, including the assimilation of one-carbon compounds such as methanol in methylotrophic bacteria and the biosynthesis of polymalic acid in fungi. The enzyme is also known as malate thiokinase or malyl-CoA synthetase, reflecting its role in activating malate for further metabolism. Researchers study this activity to understand carbon flux, CoA-dependent chemistry, and the evolution of ATP-dependent ligases. The reaction is reversible and involves a ternary complex mechanism, as shown by kinetic studies on malate thiokinase from Methylobacterium extorquens AM1. Given its involvement in microbial metabolism and potential biotechnological applications, malate-CoA ligase activity is a target for metabolic engineering and enzyme mechanism studies.
malate-CoA ligase activity At A Glance
| GO ID | GO:0050074 |
|---|---|
| GO term | malate-CoA ligase activity |
| Ontology | molecular_function |
| Synonym | malate:CoA ligase (ADP-forming); malate thiokinase activity; malyl-CoA synthetase activity; malyl coenzyme A synthetase activity |
| Major function | Catalyzes ATP-dependent formation of malyl-CoA from malate and CoA |
| Reaction | ATP + malate + CoA = ADP + phosphate + malyl-CoA |
| Enzyme class | Ligase (EC 6.2.1.-) |
| Superfamily | ATP-dependent carboxylate-amine/thiol ligase superfamily |
| Found in | Bacteria, fungi, and some archaea |
What Is GO:0050074?
According to the Gene Ontology, malate-CoA ligase activity (GO:0050074) is defined as the catalysis of the reaction: ATP + malate + CoA = ADP + phosphate + malyl-CoA. This means the enzyme uses the energy from ATP hydrolysis to join malate and coenzyme A, producing malyl-CoA, ADP, and inorganic phosphate. The activity is classified as a molecular_function and is synonymous with malate:CoA ligase (ADP-forming), malate thiokinase, malyl-CoA synthetase, and malyl coenzyme A synthetase.
Why Is malate-CoA ligase activity Important in Cell Biology?
Malate-CoA ligase activity is important because it links central carbon metabolism to CoA thioester chemistry, enabling the activation of malate for subsequent reactions in pathways such as methanol assimilation and polymalic acid biosynthesis. The enzyme also serves as a model for understanding ATP-dependent ligase mechanisms, including half-of-the-sites reactivity and random site kinetics. In biotechnology, malate-CoA ligase from Aureobasidium pullulans is part of the polymalic acid polymerization pathway, a biodegradable polymer with medical and industrial applications. Additionally, the ability of some succinate-CoA ligases to catalyze malate-CoA ligation expands the known substrate range of this enzyme family, with implications for metabolic engineering.
• Enables methanol assimilation in methylotrophic bacteria such as Methylobacterium extorquens AM1.
• Participates in polymalic acid biosynthesis in Aureobasidium pullulans, a biodegradable polymer.
• Provides a model system for studying ATP-dependent ligase mechanisms, including half-of-the-sites reactivity.
• Exhibits a random site reaction mechanism, contributing to enzyme kinetics theory.
• Belongs to a diverse superfamily of ATP-dependent carboxylate-amine/thiol ligases with broad evolutionary significance.
• Some succinate-CoA ligases can also perform malate-CoA ligation, suggesting metabolic flexibility.
• Potential target for metabolic engineering to produce value-added chemicals from malate.
• Relevant to understanding CoA-dependent pathways in microbial carbon fixation and assimilation.
Molecular Mechanism of malate-CoA ligase activity
Substrate Binding and Ternary Complex Formation
In simple terms: The enzyme first binds ATP, malate, and CoA to form a ready-to-react complex.
Malate-CoA ligase catalyzes the formation of malyl-CoA through an ordered or random ternary complex mechanism. Kinetic studies on malate thiokinase from Methylobacterium extorquens AM1 provided evidence for a random site reaction mechanism, where substrates can bind in any order. The enzyme forms a ternary complex with ATP, malate, and CoA before catalysis, as indicated by half-of-the-sites reactivity observed with methoxycarbonyl-CoA disulfide.
ATP-Dependent Activation of Malate
In simple terms: ATP is used to activate malate, making it reactive toward CoA.
The reaction proceeds via phosphorylation of malate by ATP, forming a malyl-adenylate intermediate and releasing pyrophosphate, although the exact intermediate may vary. The overall reaction is: ATP + malate + CoA = ADP + phosphate + malyl-CoA. This ATP-dependent activation is characteristic of the ATP-dependent carboxylate-amine/thiol ligase superfamily, which includes enzymes that activate carboxylates for thioester formation.
CoA Thioester Formation
In simple terms: The activated malate reacts with CoA to form malyl-CoA, a high-energy thioester.
Following activation, the malyl group is transferred to the thiol group of coenzyme A, yielding malyl-CoA and releasing ADP and phosphate. This thioester formation is analogous to succinyl-CoA formation by succinate-CoA ligases. Notably, some succinate-CoA ligases can also catalyze the conversion of malate to malyl-CoA, indicating overlapping substrate specificity within this enzyme family.
Half-of-the-Sites Reactivity and Regulation
In simple terms: The enzyme may only use half of its active sites at a time, which can regulate its activity.
Malate thiokinase exhibits half-of-the-sites reactivity, as shown by its reaction with methoxycarbonyl-CoA disulfide, where only half of the active sites are modified. This phenomenon suggests negative cooperativity or an asymmetric dimer structure. Such regulatory behavior may control flux through pathways involving malyl-CoA, such as methanol assimilation in Methylobacterium extorquens AM1.
Role in Metabolic Pathways
In simple terms: This enzyme helps convert malate into other molecules in bacteria and fungi.
In Methylobacterium extorquens AM1, malate-CoA ligase is part of the methanol assimilation pathway, where it converts malate to malyl-CoA, which is then cleaved to glyoxylate and acetyl-CoA. In Aureobasidium pullulans, the enzyme participates in the polymerization pathway of polymalic acid, a biodegradable polymer. These roles highlight the enzyme's importance in carbon metabolism and biopolymer production.
Key Genes Involved in GO:0050074 malate-CoA ligase activity
The following genes and proteins are directly associated with malate-CoA ligase activity or its metabolic context, as supported by published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| mcl (Aureobasidium pullulans) | Malate-CoA ligase in polymalic acid polymerization pathway | Biodegradable polymer production; gene cloning and expression |
| mcl (Methylobacterium extorquens AM1) | Malate thiokinase in methanol assimilation | Methanol metabolism; enzyme kinetics |
| sucC (various bacteria) | Succinyl-CoA synthetase beta subunit; can also catalyze malate-CoA ligation | Substrate specificity studies |
| sucD (various bacteria) | Succinyl-CoA synthetase alpha subunit; forms complex with SucC | Enzyme mechanism; half-of-sites reactivity |
| mcl1 (Methylobacterium extorquens AM1) | Malate-CoA ligase large subunit | Methanol assimilation pathway |
| mcl2 (Methylobacterium extorquens AM1) | Malate-CoA ligase small subunit | Methanol assimilation pathway |
| mcl (other methylotrophs) | Malate-CoA ligase homologs | Comparative enzymology |
| ATP-dependent ligase superfamily members | Diverse carboxylate-amine/thiol ligases | Evolutionary relationships |
| malyl-CoA synthetase (fungal) | Malyl-CoA synthetase activity | Polymalic acid biosynthesis |
| malate thiokinase (bacterial) | Malate thiokinase activity | Random site mechanism |
| succinate-CoA ligase (bacterial) | Succinate-CoA ligase; also malate-CoA ligase side activity | Substrate promiscuity |
| CoA ligase homologs (archaea) | Putative malate-CoA ligases | Metabolic diversity |
| mcl (Aureobasidium pullulans) recombinant | Recombinant malate-CoA ligase | Enzyme characterization |
| mcl (Methylobacterium) mutant | Mutant malate thiokinase | Half-of-sites reactivity |
| mcl (Methylobacterium) wild-type | Wild-type malate thiokinase | Kinetic mechanism |
| mcl (Methylobacterium) knockout | Knockout strain | Methanol growth phenotype |
| mcl (Aureobasidium) overexpression | Overexpression strain | Polymalic acid yield |
| mcl (E. coli recombinant) | Heterologous expression | Enzyme production |
How Is malate-CoA ligase activity Regulated?
The regulation of malate-CoA ligase activity is not extensively characterized, but studies suggest that it may be controlled at the transcriptional level in response to carbon source availability. In Methylobacterium extorquens AM1, the expression of malate thiokinase is induced during growth on methanol, indicating regulation by the methanol assimilation pathway. Additionally, half-of-the-sites reactivity observed in malate thiokinase may serve as a regulatory mechanism, potentially modulating enzyme activity in response to substrate concentrations. Further research is needed to identify specific regulators.
malate-CoA ligase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| mcl (Aureobasidium pullulans) | Polymalic acid production (biomaterial) | Overexpression in A. pullulans or heterologous host |
| mcl (Methylobacterium extorquens) | Methanol assimilation (microbial metabolism) | Knockout and growth phenotype |
| sucC/sucD (bacteria) | Succinate-CoA ligase deficiency (rare metabolic disorder) | Bacterial knockout for substrate specificity |
| mcl (other bacteria) | Microbiome metabolism | Gnotobiotic animal models with defined microbiota |
| mcl (fungal) | Fungal pathogenesis | Fungal knockout in infection models |
Malate-CoA ligase activity and metabolic disorders
Malate-CoA ligase activity is not directly linked to human metabolic disorders, as it is primarily found in bacteria and fungi. However, understanding its role in microbial metabolism can inform studies on the human gut microbiome, where methylotrophic bacteria may influence host metabolism. No direct disease associations have been reported in the literature.
Biotechnological and industrial relevance
The enzyme is relevant for the production of polymalic acid, a biodegradable polymer with potential biomedical applications, including drug delivery and tissue engineering. Malate-CoA ligase from Aureobasidium pullulans is a key enzyme in this pathway, and its manipulation could enhance polymer yield. This has implications for sustainable materials but is not a direct disease target.
Enzyme mechanism and drug discovery
Malate-CoA ligase belongs to a superfamily of ATP-dependent ligases that are targets for antibiotics in some bacteria. While no specific drugs target malate-CoA ligase, its unique mechanism and presence in pathogens could be explored for antimicrobial development. Further research is needed to establish any clinical relevance.
From malate-CoA ligase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Enzyme kinetics and mechanism | Recombinant protein in E. coli, site-directed mutagenesis |
| Role in methanol assimilation | Methylobacterium extorquens AM1 knockout |
| Polymalic acid production | Aureobasidium pullulans overexpression |
| Substrate specificity | Succinate-CoA ligase mutants |
| Half-of-sites reactivity | Malate thiokinase mutants |
| Structural studies | Crystallography of recombinant enzyme |
How to Study the malate-CoA ligase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Coupled spectrophotometric assay | ADP formation | Enzyme kinetics |
| HPLC | Malyl-CoA formation | Substrate specificity |
| Mass spectrometry | Malyl-CoA and CoA thioesters | Product identification |
| Site-directed mutagenesis | Active site residues | Mechanism studies |
| Knockout/overexpression | Gene function in vivo | Methanol assimilation |
| qRT-PCR | mRNA expression levels | Regulation studies |
| Western blot | Protein expression | Heterologous expression |
Enzyme Activity Assays
Malate-CoA ligase activity can be measured spectrophotometrically by coupling the formation of ADP to NADH oxidation via pyruvate kinase and lactate dehydrogenase, or by monitoring malyl-CoA formation using HPLC or mass spectrometry. Radioactive assays with labeled malate or CoA are also used.
Kinetic Analysis
Steady-state kinetics using varying substrate concentrations can determine kinetic parameters (Km, Vmax) and reveal the reaction mechanism (random vs. ordered). Half-of-sites reactivity can be probed using chemical modification reagents like methoxycarbonyl-CoA disulfide.
Genetic and Molecular Biology Techniques
Gene cloning, knockout, and overexpression in native or heterologous hosts (e.g., E. coli, Aureobasidium pullulans, Methylobacterium extorquens) are used to study the enzyme's physiological role. Quantitative RT-PCR and Western blotting can assess expression levels.
Structural Biology
X-ray crystallography or cryo-EM can provide structural insights into the enzyme's active site and conformational changes. However, no structure of malate-CoA ligase is currently available in the literature; structures of homologous succinate-CoA ligases may serve as templates.
How CRISPR Can Be Used to Study GO:0050074 malate-CoA ligase activity
Knockout
CRISPR-Cas9 knockout of malate-CoA ligase genes (e.g., mcl in Methylobacterium extorquens AM1) can be used to study the enzyme's essentiality for methanol assimilation and growth. Knockout strains may exhibit growth defects on methanol as a sole carbon source.
Point Mutation
Point mutations in the active site of malate-CoA ligase can be introduced using CRISPR base editing or homology-directed repair to dissect catalytic residues and mechanism. For example, mutations affecting ATP binding or CoA thioester formation can be tested for loss of activity.
Knock-in
Knock-in of epitope tags (e.g., FLAG, His6) at the endogenous locus using CRISPR can facilitate protein purification and localization studies. This approach allows expression under native regulatory control.
Overexpression
CRISPR activation (CRISPRa) or plasmid-based overexpression can increase malate-CoA ligase levels to enhance polymalic acid production in Aureobasidium pullulans or to study enzyme kinetics in a heterologous host.
How EDITGENE Supports malate-CoA ligase activity Research
Researchers studying malate-CoA ligase activity-related genes often need to determine whether a candidate gene is causally involved in metabolic pathways, enzyme mechanisms, or biopolymer production. EDITGENE provides comprehensive CRISPR-based services to create precise cell models for such investigations.
Contact EDITGENE today to design your custom CRISPR model for malate-CoA ligase activity research.
Frequently Asked Questions About malate-CoA ligase activity
What is malate-CoA ligase activity?
Malate-CoA ligase activity (GO:0050074) is the catalysis of the reaction ATP + malate + CoA = ADP + phosphate + malyl-CoA, as defined by the Gene Ontology.
What genes are involved in malate-CoA ligase activity?
Genes include mcl from Aureobasidium pullulans and Methylobacterium extorquens AM1, as well as succinate-CoA ligase genes (sucC, sucD) that can also catalyze this reaction.
What is the function of malate-CoA ligase?
It activates malate by forming malyl-CoA, a thioester that participates in methanol assimilation and polymalic acid biosynthesis.
What is the reaction catalyzed by malate-CoA ligase?
The enzyme catalyzes ATP + malate + CoA = ADP + phosphate + malyl-CoA.
What are the synonyms for malate-CoA ligase activity?
Synonyms include malate:CoA ligase (ADP-forming), malate thiokinase activity, malyl-CoA synthetase activity, and malyl coenzyme A synthetase activity.
Which organisms have malate-CoA ligase?
It is found in bacteria such as Methylobacterium extorquens and fungi such as Aureobasidium pullulans.
How is malate-CoA ligase activity measured?
It can be measured using coupled spectrophotometric assays, HPLC, or mass spectrometry to detect malyl-CoA formation.
What is the mechanism of malate-CoA ligase?
It proceeds via a random site reaction mechanism with half-of-the-sites reactivity, forming a ternary complex with ATP, malate, and CoA.
Is malate-CoA ligase involved in human disease?
No direct link to human disease has been reported; it is primarily studied in microbial metabolism and biotechnology.
What is the EC number for malate-CoA ligase?
The enzyme belongs to EC 6.2.1.-, the ligases forming carbon-sulfur bonds.
Conclusion
Malate-CoA ligase activity (GO:0050074) is a key molecular function in microbial carbon metabolism, enabling the ATP-dependent formation of malyl-CoA from malate and CoA. Its roles in methanol assimilation and polymalic acid biosynthesis, along with its unique kinetic properties such as half-of-the-sites reactivity, make it a valuable subject for enzymology and metabolic engineering. Researchers can leverage CRISPR-based models to further dissect its function and regulation.
References
- 1. Wu X et al.. 2014. [Gene cloning, expression and characterization of malate-CoA ligase in the polymerization pathway of polymalic acid from Aureobasidium pullulans].. Wei Sheng Wu Xue Bao 54(8):919-25 PMID: 25345024
- 2. Hersh LB et al.. 1982. Reaction of malate thiokinase with methoxycarbonyl-CoA disulfide. Evidence for half-of-the-sites reactivity.. J Biol Chem 257(19):11633-8 PMID: 7118900
- 3. Galperin MY et al.. 1997. A diverse superfamily of enzymes with ATP-dependent carboxylate-amine/thiol ligase activity.. Protein Sci 6(12):2639-43 PMID: 9416615
- 4. Nolte JC et al.. 2014. Novel characteristics of succinate coenzyme A (Succinate-CoA) ligases: conversion of malate to malyl-CoA and CoA-thioester formation of succinate analogues in vitro.. Appl Environ Microbiol 80(1):166-76 PMID: 24141127
- 5. Surendranathan KK et al.. 1983. Malate thiokinase. Evidence for a random site reaction mechanism.. J Biol Chem 258(6):3794-8 PMID: 6833230
- 6. Smejkalová H et al.. 2010. Methanol assimilation in Methylobacterium extorquens AM1: demonstration of all enzymes and their regulation.. PLoS One 5(10) PMID: 20957036
