GO:0043956 3-hydroxypropionyl-CoA dehydratase activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0043956 defines the enzymatic activity that converts 3-hydroxypropionyl-CoA to acryloyl-CoA and water, a key step in 3-hydroxypropionate/4-hydroxybutyrate (3HP/4HB) carbon fixation cycles.
• The enzyme is a member of the enoyl-CoA hydratase/isomerase superfamily and typically functions as a bifunctional crotonyl-CoA hydratase/3-hydroxypropionyl-CoA dehydratase in archaea such as Nitrosopumilus maritimus and Metallosphaera sedula.
• Structural studies reveal a conserved enoyl-CoA hydratase fold with a unique substrate-binding pocket that accommodates the hydroxyl group of 3-hydroxypropionyl-CoA, enabling catalysis via an enolized intermediate.
• This activity is essential for autotrophic carbon fixation in ammonia-oxidizing archaea and thermoacidophilic archaea, linking it to global carbon and nitrogen cycles.
• In humans, no direct ortholog of this archaeal enzyme is known, but the reaction is chemically analogous to steps in mitochondrial fatty acid oxidation and may inform studies of related metabolic disorders.
• Research on GO:0043956 benefits from CRISPR-based knockout, knock-in, and overexpression models in archaeal and bacterial hosts to dissect pathway flux and enzyme specificity.
Description
3-hydroxypropionyl-CoA dehydratase activity (GO:0043956) is a molecular function that catalyzes the dehydration of 3-hydroxypropionyl-CoA to acryloyl-CoA and water. This reaction is a critical step in the 3-hydroxypropionate/4-hydroxybutyrate (3HP/4HB) cycle, a pathway used by certain archaea for autotrophic carbon fixation. The enzyme belongs to the enoyl-CoA hydratase/isomerase superfamily and often exhibits bifunctional activity, also acting on crotonyl-CoA. Understanding this activity is important for researchers studying archaeal metabolism, carbon cycling, and the evolution of metabolic pathways. The unique substrate specificity and catalytic mechanism have been elucidated through structural and biochemical studies, providing insights into enzyme evolution and potential biotechnological applications.
3-hydroxypropionyl-CoA dehydratase activity At A Glance
| GO ID | GO:0043956 |
|---|---|
| GO term | 3-hydroxypropionyl-CoA dehydratase activity |
| Ontology | molecular_function |
| Synonym | 3-hydroxy propionyl-CoA dehydratase activity; acetyl-coenzyme A synthetase; acetyl-coenzyme A synthetase/GroES-like domain; AMP-dependent synthetase and ligase; AMP-dependent synthetase and ligase:Enoyl-CoA hydratase/isomerase; enoyl-CoA hydratase/isomerase |
| Major function | Catalyzes the dehydration of 3-hydroxypropionyl-CoA to acryloyl-CoA and water |
| Reaction | 3-hydroxypropionyl-CoA = acryloyl-CoA + H2O |
| Enzyme family | Enoyl-CoA hydratase/isomerase superfamily |
| Pathway context | 3-hydroxypropionate/4-hydroxybutyrate (3HP/4HB) cycle |
| Organisms | Archaea (e.g., Nitrosopumilus maritimus, Metallosphaera sedula) |
What Is GO:0043956?
According to the Gene Ontology, GO:0043956 is defined as the catalysis of the reaction: 3-hydroxypropionyl-CoA = acryloyl-CoA + H2O. In other words, it is the enzyme activity that removes a water molecule from 3-hydroxypropionyl-CoA to form acryloyl-CoA, a key dehydration step in certain carbon fixation pathways.
Why Is 3-hydroxypropionyl-CoA dehydratase activity Important in Cell Biology?
GO:0043956 is important because it represents a key enzymatic step in the 3-hydroxypropionate/4-hydroxybutyrate cycle, a pathway that allows archaea to fix carbon dioxide autotrophically. This cycle contributes to global carbon cycling, particularly in marine environments where ammonia-oxidizing archaea are abundant. The enzyme's bifunctional nature and unique substrate specificity also make it a model for studying enzyme evolution and catalytic promiscuity. Additionally, understanding this activity can inform metabolic engineering efforts to produce acryloyl-CoA and related compounds from renewable resources.
• Key step in the 3-hydroxypropionate/4-hydroxybutyrate (3HP/4HB) carbon fixation cycle in archaea.
• Contributes to global carbon cycling by marine ammonia-oxidizing archaea such as Nitrosopumilus maritimus.
• Provides a model for studying enoyl-CoA hydratase/isomerase superfamily mechanisms and substrate specificity.
• Bifunctional activity (crotonyl-CoA hydratase and 3-hydroxypropionyl-CoA dehydratase) illustrates enzyme multifunctionality.
• Potential target for biotechnological production of acryloyl-CoA and derivatives.
• Structural insights aid in understanding dehydration mechanisms and enolized intermediates.
• Relevant to evolutionary studies of metabolic pathways in extremophiles.
• May inform synthetic biology approaches for carbon fixation.
• Helps elucidate the role of archaea in nitrogen and carbon cycles.
• Offers a basis for comparative enzymology with mitochondrial fatty acid oxidation enzymes.
Molecular Mechanism of 3-hydroxypropionyl-CoA dehydratase activity
Substrate Binding and Specificity
In simple terms: The enzyme grabs 3-hydroxypropionyl-CoA and positions it for a chemical reaction.
Structural studies of the bifunctional crotonyl-CoA hydratase/3-hydroxypropionyl-CoA dehydratase from Nitrosopumilus maritimus and the 3-hydroxypropionyl-CoA dehydratase from Metallosphaera sedula reveal a conserved enoyl-CoA hydratase fold with a substrate-binding pocket that accommodates the hydroxyl group of 3-hydroxypropionyl-CoA. The enzyme discriminates between 3-hydroxypropionyl-CoA and crotonyl-CoA through specific interactions, enabling dual activity.
Catalytic Dehydration
In simple terms: The enzyme removes a water molecule from the substrate to form a double bond.
The dehydration reaction proceeds via an enolized intermediate, as proposed by D'Ordine et al. based on enoyl-CoA hydratase-catalyzed exchange of alpha-protons of coenzyme A thiol esters. The catalytic mechanism involves general acid-base chemistry, with conserved residues abstracting and donating protons to facilitate water elimination and double bond formation.
Bifunctional Activity
In simple terms: Some versions of this enzyme can also catalyze a related reaction on a different substrate.
The thaumarchaeal enzyme from Nitrosopumilus maritimus is bifunctional, acting as both a crotonyl-CoA hydratase and a 3-hydroxypropionyl-CoA dehydratase. This bifunctionality is structurally enabled by a flexible active site that can accommodate both substrates, as shown by crystallographic and biochemical analyses.
Role in the 3HP/4HB Cycle
In simple terms: This enzyme is one step in a larger cycle that fixes carbon dioxide.
In the 3-hydroxypropionate/4-hydroxybutyrate cycle, 3-hydroxypropionyl-CoA dehydratase converts 3-hydroxypropionyl-CoA to acryloyl-CoA, which is subsequently reduced to propionyl-CoA. This step is essential for the regeneration of acetyl-CoA and the overall fixation of carbon dioxide in archaea such as Metallosphaera sedula and Nitrosopumilus maritimus.
Structural Determinants
In simple terms: The 3D shape of the enzyme explains how it works.
Crystal structures of the enzyme from Metallosphaera sedula and Nitrosopumilus maritimus reveal a trimeric or hexameric assembly with a conserved enoyl-CoA hydratase domain. Key residues in the active site, including glutamate and histidine, are positioned to catalyze the dehydration reaction, and mutations of these residues abolish activity.
Key Genes Involved in GO:0043956 3-hydroxypropionyl-CoA dehydratase activity
The following genes and proteins are directly associated with 3-hydroxypropionyl-CoA dehydratase activity or its pathway context.
| Gene | Major Role | Research Relevance |
|---|---|---|
| Nmar_1308 | Bifunctional crotonyl-CoA hydratase/3-hydroxypropionyl-CoA dehydratase in Nitrosopumilus maritimus | Structural and biochemical studies of bifunctional activity |
| Msed_2001 | 3-hydroxypropionyl-CoA dehydratase in Metallosphaera sedula | Substrate specificity and structural insights |
| Msed_1423 | (S)-3-hydroxybutyryl-CoA dehydrogenase in Metallosphaera sedula | Adjacent step in 3HP/4HB cycle |
| Nmar_1309 | (S)-3-hydroxybutyryl-CoA dehydrogenase in Nitrosopumilus maritimus | Adjacent step in 3HP/4HB cycle |
| Nmar_1307 | Crotonyl-CoA hydratase in Nitrosopumilus maritimus | Bifunctional partner of Nmar_1308 |
| Msed_0399 | Acetyl-CoA carboxylase in Metallosphaera sedula | Upstream step in 3HP/4HB cycle |
| Msed_0709 | Malonyl-CoA reductase in Metallosphaera sedula | Upstream step in 3HP/4HB cycle |
| Msed_1993 | 3-hydroxypropionyl-CoA synthetase in Metallosphaera sedula | Upstream step in 3HP/4HB cycle |
| Msed_1426 | Acryloyl-CoA reductase in Metallosphaera sedula | Downstream step in 3HP/4HB cycle |
| Nmar_1310 | Acryloyl-CoA reductase in Nitrosopumilus maritimus | Downstream step in 3HP/4HB cycle |
| Nmar_1311 | Methylmalonyl-CoA epimerase in Nitrosopumilus maritimus | Downstream step in 3HP/4HB cycle |
| Nmar_1312 | Methylmalonyl-CoA mutase in Nitrosopumilus maritimus | Downstream step in 3HP/4HB cycle |
| Msed_1424 | Methylmalonyl-CoA epimerase in Metallosphaera sedula | Downstream step in 3HP/4HB cycle |
| Msed_1425 | Methylmalonyl-CoA mutase in Metallosphaera sedula | Downstream step in 3HP/4HB cycle |
| Msed_2000 | 3-hydroxypropionyl-CoA dehydratase homolog in Metallosphaera sedula | Potential paralog or isozyme |
| Nmar_1306 | Enoyl-CoA hydratase homolog in Nitrosopumilus maritimus | Potential accessory protein |
| Msed_0398 | Biotin carboxylase in Metallosphaera sedula | Upstream step in 3HP/4HB cycle |
| Msed_0708 | Malonyl-CoA reductase homolog in Metallosphaera sedula | Upstream step in 3HP/4HB cycle |
How Is 3-hydroxypropionyl-CoA dehydratase activity Regulated?
The regulation of 3-hydroxypropionyl-CoA dehydratase activity is not well characterized in the provided literature. However, in the context of the 3HP/4HB cycle, its expression is likely coordinated with other cycle enzymes to respond to carbon availability. No specific transcriptional regulators or post-translational modifications have been reported in the cited studies.
3-hydroxypropionyl-CoA dehydratase activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| Nmar_1308 | Not directly linked to disease; model for carbon fixation | Knockout in Nitrosopumilus maritimus |
| Msed_2001 | Not directly linked to disease; model for enzyme specificity | Knockout in Metallosphaera sedula |
| Human ECHS1 | Mitochondrial short-chain enoyl-CoA hydratase deficiency | Knockout in human cell lines |
| Human HADHA | Mitochondrial trifunctional protein deficiency | Knockout in human cell lines |
| Human HADHB | Mitochondrial trifunctional protein deficiency | Knockout in human cell lines |
No Direct Human Disease Association
3-hydroxypropionyl-CoA dehydratase activity (GO:0043956) is primarily found in archaea and has no known direct ortholog in humans. Therefore, it is not directly linked to human diseases. However, the chemical reaction it catalyzes is analogous to steps in mitochondrial fatty acid oxidation, which are relevant to metabolic disorders.
Relevance to Metabolic Disorders
Enoyl-CoA hydratase deficiencies in humans cause disorders such as 3-hydroxyacyl-CoA dehydrogenase deficiency and mitochondrial trifunctional protein deficiency. While GO:0043956 itself is not implicated, studying its mechanism can provide insights into the general principles of enoyl-CoA hydratases and their role in disease.
Biotechnological and Environmental Impact
The enzyme's role in carbon fixation by archaea links it to global carbon cycling and climate regulation. Understanding its function could inform strategies for carbon capture and synthetic biology, indirectly affecting environmental health.
From 3-hydroxypropionyl-CoA dehydratase activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| What is the effect of loss of 3-hydroxypropionyl-CoA dehydratase on autotrophic growth? | Knockout of Nmar_1308 or Msed_2001 in archaeal hosts |
| How does a point mutation in the active site affect catalysis? | Point mutation of catalytic residues (e.g., Glu, His) in Nmar_1308 or Msed_2001 |
| Can the enzyme be tagged for localization studies? | Knock-in of affinity tags (e.g., His-tag) at the endogenous locus |
| What is the effect of overexpression on pathway flux? | Overexpression of Nmar_1308 or Msed_2001 in archaeal or bacterial hosts |
| How does substrate specificity change with mutations? | Site-directed mutagenesis and kinetic assays |
| What is the role of bifunctionality in vivo? | Knockout of bifunctional enzyme and complementation with monofunctional variants |
How to Study the 3-hydroxypropionyl-CoA dehydratase activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| X-ray crystallography | Three-dimensional structure | Determining active site architecture |
| Enzyme kinetics | Catalytic parameters (kcat, Km) | Characterizing substrate specificity |
| Metabolomics | Intracellular metabolite levels | Pathway flux analysis |
| CRISPR knockout | Gene essentiality | Testing growth phenotypes |
| Site-directed mutagenesis | Effect of point mutations | Identifying catalytic residues |
| Isothermal titration calorimetry | Binding affinity | Substrate binding studies |
| Analytical ultracentrifugation | Oligomeric state | Assembly studies |
| Circular dichroism | Protein folding | Stability assays |
Structural Biology
X-ray crystallography and cryo-EM can determine the three-dimensional structure of 3-hydroxypropionyl-CoA dehydratase, revealing substrate-binding pockets and catalytic residues. These methods are essential for understanding the mechanism and for designing inhibitors or engineering variants.
Enzyme Kinetics
Kinetic assays using purified enzyme and substrate analogs measure catalytic efficiency, substrate specificity, and the effects of mutations. Such assays can confirm the dehydration reaction and identify rate-limiting steps.
Metabolomics
Metabolomic profiling of archaeal cells grown under autotrophic conditions can quantify intracellular levels of 3-hydroxypropionyl-CoA, acryloyl-CoA, and other cycle intermediates, providing insights into pathway flux.
Genetic Knockouts
CRISPR-based or homologous recombination knockout of the gene encoding 3-hydroxypropionyl-CoA dehydratase can reveal its essentiality for autotrophic growth and its role in the 3HP/4HB cycle.
How CRISPR Can Be Used to Study GO:0043956 3-hydroxypropionyl-CoA dehydratase activity
Knockout
CRISPR-Cas9 can be used to generate knockout mutants of genes encoding 3-hydroxypropionyl-CoA dehydratase in archaeal or bacterial hosts, such as Nmar_1308 in Nitrosopumilus maritimus or Msed_2001 in Metallosphaera sedula. These knockouts help determine the essentiality of the enzyme for autotrophic growth and carbon fixation.
Point Mutation
CRISPR-based base editing or homology-directed repair can introduce point mutations in catalytic residues (e.g., glutamate or histidine) to dissect the mechanism of dehydration. Such mutants can be tested for loss of activity and structural changes.
Knock-in
Knock-in of epitope tags (e.g., FLAG, His) at the endogenous locus allows for protein purification and localization studies without altering expression levels. This is useful for structural and biochemical analyses.
Overexpression
CRISPR activation (CRISPRa) or plasmid-based overexpression can increase enzyme levels to study pathway flux and substrate channeling in vivo. Overexpression in heterologous hosts like Escherichia coli can facilitate large-scale purification.
How EDITGENE Supports 3-hydroxypropionyl-CoA dehydratase activity Research
Researchers studying 3-hydroxypropionyl-CoA dehydratase activity-related genes often need to determine whether a candidate gene is causally involved in carbon fixation, enzyme mechanism, or metabolic pathway regulation. EDITGENE provides comprehensive CRISPR-based services to accelerate this research.
Contact EDITGENE today to design your custom CRISPR model for 3-hydroxypropionyl-CoA dehydratase activity research.
Frequently Asked Questions About 3-hydroxypropionyl-CoA dehydratase activity
What is 3-hydroxypropionyl-CoA dehydratase activity?
It is an enzymatic activity (GO:0043956) that catalyzes the dehydration of 3-hydroxypropionyl-CoA to acryloyl-CoA and water, a step in the 3HP/4HB carbon fixation cycle.
What genes are involved in 3-hydroxypropionyl-CoA dehydratase activity?
Genes such as Nmar_1308 in Nitrosopumilus maritimus and Msed_2001 in Metallosphaera sedula encode bifunctional enzymes with this activity.
Which organisms have 3-hydroxypropionyl-CoA dehydratase?
It is found in archaea, particularly ammonia-oxidizing archaea like Nitrosopumilus maritimus and thermoacidophilic archaea like Metallosphaera sedula.
What is the reaction catalyzed by 3-hydroxypropionyl-CoA dehydratase?
The enzyme converts 3-hydroxypropionyl-CoA to acryloyl-CoA and water.
How is 3-hydroxypropionyl-CoA dehydratase regulated?
Regulation is not well understood, but expression is likely coordinated with other 3HP/4HB cycle enzymes in response to carbon availability.
What diseases are associated with 3-hydroxypropionyl-CoA dehydratase?
No direct human diseases are linked to this archaeal enzyme, but its mechanism is analogous to human enoyl-CoA hydratases involved in metabolic disorders.
What is the structure of 3-hydroxypropionyl-CoA dehydratase?
It adopts an enoyl-CoA hydratase fold and can form trimers or hexamers, with a conserved active site.
Can I study 3-hydroxypropionyl-CoA dehydratase using CRISPR?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression can be used in archaeal or heterologous hosts.
What methods are used to measure 3-hydroxypropionyl-CoA dehydratase activity?
Enzyme kinetics, metabolomics, and structural biology are common methods.
Why is 3-hydroxypropionyl-CoA dehydratase important for carbon fixation?
It is a key step in the 3HP/4HB cycle, which allows archaea to fix carbon dioxide autotrophically.
Conclusion
3-hydroxypropionyl-CoA dehydratase activity (GO:0043956) is a critical enzymatic function in the 3-hydroxypropionate/4-hydroxybutyrate cycle of archaea, enabling autotrophic carbon fixation. Structural and biochemical studies have elucidated its bifunctional mechanism and substrate specificity. While not directly linked to human disease, it serves as a model for enoyl-CoA hydratase mechanisms and has potential biotechnological applications. Continued research using CRISPR-based models will further illuminate its role in carbon cycling and metabolic engineering.
References
- 1. Destan E et al.. 2021. Structural insights into bifunctional thaumarchaeal crotonyl-CoA hydratase and 3-hydroxypropionyl-CoA dehydratase from Nitrosopumilus maritimus.. Sci Rep 11(1):22849 PMID: 34819551
- 2. Lee D et al.. 2018. Structural Insight into Substrate Specificity of 3-Hydroxypropionyl-Coenzyme A Dehydratase from Metallosphaera sedula.. Sci Rep 8(1):10692 PMID: 30013155
- 3. Liu L et al.. 2021. (S)-3-Hydroxybutyryl-CoA Dehydrogenase From the Autotrophic 3-Hydroxypropionate/4-Hydroxybutyrate Cycle in Nitrosopumilus maritimus.. Front Microbiol 12:712030 PMID: 34290692
- 4. D'Ordine RL et al.. 1994. Enoyl-coenzyme A hydratase-catalyzed exchange of the alpha-protons of coenzyme A thiol esters: a model for an enolized intermediate in the enzyme-catalyzed elimination?. Biochemistry 33(49):14733-42 PMID: 7993901
