GO:1990362 butanol dehydrogenase (NAD+) activity: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:1990362 butanol dehydrogenase (NAD+) activity catalyzes the reversible oxidation of butan-1-ol to butanal with concomitant reduction of NAD+ to NADH.
• The enzyme belongs to the alcohol dehydrogenase superfamily and has been structurally and biochemically characterized in Thermotoga maritima and Fusobacterium nucleatum.
• NAD-dependent butanol dehydrogenases are central to microbial butanol metabolism, including solvent production in Clostridium acetobutylicum and butane oxidation in Pseudomonas butanovora.
• Biochemical studies have revealed diverse quaternary structures, metal requirements, and substrate specificities among butanol dehydrogenases from different organisms.
• Butanol dehydrogenase activity is relevant to industrial biotechnology for biofuel production and to understanding microbial solvent tolerance and degradation.
• CRISPR-based knockout, point mutation, knock-in, and overexpression models enable causal dissection of butanol dehydrogenase function in native and heterologous hosts.
Description
Butanol dehydrogenase (NAD+) activity, formally annotated as GO:1990362, is a molecular function defined by the reversible conversion of butan-1-ol and NAD+ to butanal, a proton, and NADH. This enzymatic activity is widely distributed among bacteria and fungi, where it participates in both the production and degradation of butanol and related alcohols. The reaction is thermodynamically reversible and depends on the nicotinamide cofactor NAD+, distinguishing it from quinone-dependent or NADP-dependent alcohol oxidoreductases. Because butanol is a valuable industrial solvent and biofuel precursor, understanding the enzymes that interconvert butanol and butanal has attracted sustained research interest. Structural and biochemical studies of butanol dehydrogenases from Thermotoga maritima and Fusobacterium nucleatum have provided atomic-level insights into substrate binding, cofactor specificity, and catalytic mechanism. In parallel, classical purification and characterization work on enzymes from Enterobacter sp. VKGH12, Pseudomonas butanovora, Fusarium merismoides, and Pectobacterium atrosepticum has defined the kinetic and physical properties of this activity across diverse taxa. The gene adhE2 from Clostridium acetobutylicum encodes a bifunctional aldehyde/alcohol dehydrogenase responsible for butanol production in alcohologenic cultures, directly linking GO:1990362 to solventogenesis. Similarly, a bifunctional aldehyde/alcohol dehydrogenase from Thermoanaerobacter mathranii has been identified and overexpressed for ethanol production, illustrating the broader aldehyde/alcohol dehydrogenase family context. Researchers studying microbial metabolism, biofuel pathways, and enzyme evolution therefore rely on GO:1990362 as a precise functional annotation for comparative genomics and metabolic engineering.
butanol dehydrogenase (NAD+) activity At A Glance
| GO ID | GO:1990362 |
|---|---|
| GO term | butanol dehydrogenase (NAD+) activity |
| Ontology | molecular_function |
| Synonym | butanol dehydrogenase activity |
| Definition | Catalysis of the reaction: butan-1-ol + NAD+ = butanal + H+ + NADH |
| Major function | Reversible NAD-dependent oxidation of butan-1-ol to butanal |
| Cofactor | NAD+ (nicotinamide adenine dinucleotide, oxidized form) |
| Representative organisms | Thermotoga maritima, Fusobacterium nucleatum, Enterobacter sp. VKGH12, Pseudomonas butanovora, Clostridium acetobutylicum |
| Related activity | Aldehyde/alcohol dehydrogenase (bifunctional) in solventogenic Clostridia |
What Is GO:1990362?
GO:1990362 butanol dehydrogenase (NAD+) activity is defined as the catalysis of the reaction: butan-1-ol + NAD+ = butanal + H+ + NADH. In other words, it is the NAD-dependent oxidoreduction of butan-1-ol to butanal, with NAD+ serving as the electron acceptor. The activity is reversible, allowing the enzyme to reduce butanal to butanol when NADH is available. This definition excludes quinohaemoprotein alcohol dehydrogenases that use pyrroloquinoline quinone rather than NAD+, and it distinguishes the activity from NADP-dependent or NAD(P)-independent alcohol dehydrogenases.
Why Is butanol dehydrogenase (NAD+) activity Important in Cell Biology?
GO:1990362 is important because it defines a central enzymatic step in microbial butanol metabolism, a pathway with direct implications for biofuel production, solvent tolerance, and bioremediation. The ability to interconvert butanol and butanal also connects to broader aldehyde/alcohol dehydrogenase functions that are critical for redox balance and energy metabolism in anaerobic bacteria. Understanding the structural and kinetic basis of this activity informs enzyme engineering for industrial biotechnology and provides a model for studying NAD-dependent oxidoreductases more generally.
• Defines a key step in microbial butanol production and degradation pathways.
• Enables comparative genomics and functional annotation of alcohol dehydrogenases.
• Provides a target for metabolic engineering of biofuel-producing strains.
• Contributes to understanding solvent tolerance mechanisms in bacteria.
• Serves as a model for NAD-dependent oxidoreductase mechanism and cofactor specificity.
• Links to aldehyde/alcohol dehydrogenase bifunctional enzymes in solventogenic Clostridia.
• Relevant to butane oxidation and assimilation in Pseudomonas butanovora.
• Informs studies of fungal and bacterial alcohol metabolism.
• Supports structure-function studies of thermostable and mesophilic enzymes.
• Facilitates development of biosensors and biocatalysts for butanol detection and conversion.
Molecular Mechanism of butanol dehydrogenase (NAD+) activity
Substrate binding and specificity
In simple terms: The enzyme grabs butanol and NAD+ and holds them in place for the reaction.
Butanol dehydrogenases bind butan-1-ol and NAD+ in a defined active site. Structural analysis of the Thermotoga maritima enzyme revealed a typical alcohol dehydrogenase fold with a catalytic zinc ion and a Rossmann-like NAD-binding domain. The Fusobacterium nucleatum enzyme similarly shows a conserved active site architecture accommodating butanol as substrate. Substrate specificity studies on the Enterobacter sp. VKGH12 enzyme demonstrated NAD-dependent oxidation of n-butanol, with activity against related primary alcohols. The Pseudomonas butanovora enzyme, by contrast, is a quinohaemoprotein that oxidizes butanol using a different electron acceptor, highlighting the distinctness of GO:1990362.
Catalytic mechanism and cofactor role
In simple terms: NAD+ takes electrons from butanol, turning it into butanal and becoming NADH.
The catalytic mechanism involves hydride transfer from the alcohol carbon to the nicotinamide ring of NAD+, yielding butanal and NADH. This is consistent with the defined reaction for GO:1990362. The reaction is reversible, and in solventogenic Clostridium acetobutylicum, the bifunctional aldehyde/alcohol dehydrogenase encoded by adhE2 catalyzes the NADH-dependent reduction of butyraldehyde to butanol during alcohologenic growth. The Thermoanaerobacter mathranii bifunctional aldehyde/alcohol dehydrogenase similarly uses NADH for alcohol production, underscoring the role of NAD(H) in these reactions.
Metal ion dependence and structural classes
In simple terms: Some versions of the enzyme need a metal ion to work, while others do not.
Group III alcohol dehydrogenases, such as the enzyme from Pectobacterium atrosepticum, contain a metal ion-containing region and exhibit NAD-dependent activity. The Thermotoga maritima butanol dehydrogenase is a zinc-dependent enzyme. In contrast, the Fusarium merismoides 4-N-trimethylamino-1-butanol dehydrogenase was purified and characterized without reported metal dependence, illustrating diversity within butanol-oxidizing enzymes. These differences reflect distinct evolutionary solutions for catalyzing the same overall chemistry.
Quaternary structure and oligomerization
In simple terms: The enzyme can be made of one or several protein chains stuck together.
Butanol dehydrogenases vary in quaternary structure. The Enterobacter sp. VKGH12 enzyme was purified and characterized as a NAD-dependent n-butanol dehydrogenase with a defined oligomeric state. Structural studies of the Thermotoga maritima and Fusobacterium nucleatum enzymes provide high-resolution views of their assembly and active-site organization. The Pectobacterium atrosepticum Group III alcohol dehydrogenase was analyzed for its enzymatic activity and metal ion-containing region, contributing to understanding of oligomerization and domain architecture.
Regulation and expression context
In simple terms: Cells control when and how much of this enzyme they make.
Expression of butanol dehydrogenase genes is often regulated in response to substrate availability and metabolic state. In Clostridium acetobutylicum, adhE2 is transcribed in alcohologenic cultures, linking its expression to solvent production. The Pseudomonas butanovora 1-butanol dehydrogenase is inducible and involved in butane oxidation, indicating substrate-dependent regulation. These examples show that GO:1990362 activity is integrated into broader metabolic and regulatory networks.
Key Genes Involved in GO:1990362 butanol dehydrogenase (NAD+) activity
The following genes and proteins are experimentally linked to butanol dehydrogenase (NAD+) activity or closely related aldehyde/alcohol dehydrogenase functions.
| Gene | Major Role | Research Relevance |
|---|---|---|
| adhE2 (Clostridium acetobutylicum) | Bifunctional aldehyde/alcohol dehydrogenase for butanol production | Key enzyme in solventogenesis; studied for biofuel engineering |
| Butanol dehydrogenase (Thermotoga maritima) | NAD-dependent oxidation of butanol | Structural and biochemical model for thermostable enzyme |
| Butanol dehydrogenase (Fusobacterium nucleatum) | NAD-dependent butanol oxidation | Structural and biochemical characterization |
| n-Butanol dehydrogenase (Enterobacter sp. VKGH12) | NAD-dependent n-butanol oxidation | Purification and characterization from solvent-tolerant bacterium |
| 1-Butanol dehydrogenase (Pseudomonas butanovora) | Quinohaemoprotein alcohol oxidation in butane metabolism | Inducible enzyme involved in butane oxidation |
| 4-N-trimethylamino-1-butanol dehydrogenase (Fusarium merismoides) | Oxidation of a butanol derivative | Fungal enzyme purification and characterization |
| Group III alcohol dehydrogenase (Pectobacterium atrosepticum) | Metal ion-containing alcohol dehydrogenase | Insights into enzymatic activity and metal region |
| Bifunctional aldehyde/alcohol dehydrogenase (Thermoanaerobacter mathranii) | Ethanol production via aldehyde reduction | Overexpression for biofuel applications |
| NAD+ | Essential cofactor for hydride transfer | Central to GO:1990362 reaction |
| NADH | Reduced cofactor product | Drives reverse reaction to butanol |
| Butan-1-ol | Substrate for oxidation | Defines substrate specificity |
| Butanal | Product of oxidation | Intermediate in butanol metabolism |
| Zinc ion | Catalytic metal in some butanol dehydrogenases | Structural cofactor in Thermotoga maritima enzyme |
| Pyrroloquinoline quinone | Cofactor in quinohaemoprotein butanol dehydrogenase | Distinguishes from NAD-dependent activity |
| Aldehyde dehydrogenase domain | Catalytic domain in bifunctional enzymes | Links to butanol production pathways |
| Alcohol dehydrogenase domain | Catalytic domain for alcohol oxidation | Core of GO:1990362 activity |
How Is butanol dehydrogenase (NAD+) activity Regulated?
Expression and activity of butanol dehydrogenases are regulated at multiple levels. In Clostridium acetobutylicum, adhE2 transcription is induced in alcohologenic cultures, coordinating butanol production with solventogenic metabolism. The Pseudomonas butanovora 1-butanol dehydrogenase is inducible by butane, reflecting substrate-dependent regulation. At the enzyme level, activity depends on NAD+ availability and redox balance, as the reaction is reversible and sensitive to the NADH/NAD+ ratio. Metal ion availability may also influence the activity of metal-dependent enzymes such as the Thermotoga maritima butanol dehydrogenase and the Pectobacterium atrosepticum Group III alcohol dehydrogenase.
butanol dehydrogenase (NAD+) activity and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| Fusobacterium nucleatum butanol dehydrogenase | Periodontal disease and colorectal cancer association | Bacterial knockout and infection models |
| Clostridium acetobutylicum adhE2 | Solvent production and industrial fermentation | Gene knockout and overexpression in Clostridium |
| Enterobacter sp. VKGH12 n-butanol dehydrogenase | Solvent tolerance and degradation | Knockout and heterologous expression |
| Pseudomonas butanovora 1-butanol dehydrogenase | Butane oxidation and bioremediation | Inducible expression and mutant analysis |
| Thermoanaerobacter mathranii aldehyde/alcohol dehydrogenase | Bioethanol production | Overexpression in thermophilic hosts |
Butanol dehydrogenase and microbial pathogenesis
Butanol dehydrogenase activity is not directly linked to a specific human disease, but it contributes to the metabolic versatility of bacteria such as Fusobacterium nucleatum, an organism associated with periodontal disease and colorectal cancer. The ability to metabolize alcohols may influence the survival and virulence of such pathogens in host environments, although direct causal evidence remains to be established.
Relevance to metabolic disorders and alcohol metabolism
The broader family of NAD-dependent alcohol dehydrogenases is central to alcohol metabolism in humans, but GO:1990362 specifically describes a microbial and fungal activity. No direct human disease association has been reported for this exact enzymatic activity in the cited literature. Researchers should avoid extrapolating microbial butanol dehydrogenase function to human alcohol dehydrogenase pathologies without experimental validation.
Industrial and environmental health implications
Butanol is an industrial solvent with toxic effects on humans, and microbial butanol dehydrogenases participate in its degradation and production. Understanding these enzymes can inform bioremediation strategies for butanol-contaminated environments and improve safety in industrial biotechnology. However, no specific human disease is directly caused by defects in GO:1990362 activity based on the available literature.
From butanol dehydrogenase (NAD+) activity-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of butanol dehydrogenase affect butanol metabolism? | CRISPR knockout in native host |
| How does a point mutation alter catalytic activity? | CRISPR point mutation at active-site residues |
| Can a tagged enzyme be used for localization studies? | Knock-in of affinity or fluorescent tag |
| Does overexpression increase butanol production? | CRISPR overexpression or promoter knock-in |
| Is the enzyme functionally conserved across species? | Heterologous expression and complementation |
| What is the substrate specificity of a novel homolog? | Knockout of native gene plus expression of variant |
How to Study the butanol dehydrogenase (NAD+) activity Process
| Method | What It Measures | Typical Application |
|---|---|---|
| NADH absorbance assay | Enzyme activity via NADH production | Kinetic characterization of butanol dehydrogenase |
| X-ray crystallography | Three-dimensional structure | Active-site and cofactor binding analysis |
| Site-directed mutagenesis | Role of specific residues | Catalytic mechanism studies |
| RT-qPCR | Gene expression levels | Transcriptional regulation of adhE2 |
| Heterologous expression | Functional production of enzyme | Characterization of enzymes from diverse hosts |
| Overexpression | Increased enzyme levels | Biofuel production enhancement |
| Purification and kinetics | Substrate specificity and kinetic parameters | Enzyme characterization |
| Inducible expression analysis | Substrate-dependent regulation | Butane oxidation studies |
Enzymatic activity assays
Butanol dehydrogenase activity is typically measured by monitoring NADH formation at 340 nm using butan-1-ol as substrate and NAD+ as cofactor. Purification and characterization studies on the Enterobacter sp. VKGH12 enzyme established standard kinetic assays for this activity. Similar assays were used for the Fusarium merismoides enzyme and the Pectobacterium atrosepticum Group III alcohol dehydrogenase.
Structural biology
X-ray crystallography and biochemical analysis have been used to determine the structures of butanol dehydrogenases from Thermotoga maritima and Fusobacterium nucleatum, revealing active-site architecture and cofactor binding. These studies provide templates for homology modeling and structure-guided mutagenesis.
Transcriptional and expression analysis
Transcriptional analysis of adhE2 in Clostridium acetobutylicum revealed its induction in alcohologenic cultures, linking gene expression to butanol production. Similar approaches can be applied to other butanol dehydrogenase genes to study regulation.
Heterologous expression and engineering
Overexpression of the Thermoanaerobacter mathranii bifunctional aldehyde/alcohol dehydrogenase was used to enhance ethanol production, demonstrating the utility of heterologous expression for functional studies. Heterologous expression is also valuable for characterizing enzymes from organisms that are difficult to culture.
How CRISPR Can Be Used to Study GO:1990362 butanol dehydrogenase (NAD+) activity
Knockout
CRISPR knockout of butanol dehydrogenase genes can abolish butanol oxidation or production, enabling causal tests of enzyme function in native hosts such as Clostridium acetobutylicum or Enterobacter sp.. Knockout strains can be used to measure metabolic flux changes and solvent tolerance.
Point Mutation
CRISPR point mutation can be used to alter active-site residues identified in structural studies of Thermotoga maritima and Fusobacterium nucleatum butanol dehydrogenases, allowing precise testing of catalytic mechanism and cofactor specificity.
Knock-in
Knock-in of epitope tags or fluorescent proteins at the endogenous locus enables localization and interaction studies of butanol dehydrogenases without altering expression levels, as demonstrated for related alcohol dehydrogenases.
Overexpression
CRISPR activation or promoter knock-in can drive overexpression of butanol dehydrogenase genes to enhance butanol production or degradation, as shown for the Thermoanaerobacter mathranii aldehyde/alcohol dehydrogenase and adhE2 in Clostridium acetobutylicum.
How EDITGENE Supports butanol dehydrogenase (NAD+) activity Research
Researchers studying butanol dehydrogenase (NAD+) activity-related genes often need to determine whether a candidate gene is causally involved in butanol metabolism, solvent tolerance, or biofuel production. EDITGENE provides comprehensive CRISPR-based services to generate precisely engineered cell models for such functional studies.
Contact EDITGENE today to design your custom CRISPR model for butanol dehydrogenase (NAD+) activity research.
Frequently Asked Questions About butanol dehydrogenase (NAD+) activity
What is butanol dehydrogenase (NAD+) activity?
It is the enzymatic activity defined by GO:1990362 that catalyzes the reversible conversion of butan-1-ol and NAD+ to butanal, a proton, and NADH.
What genes are involved in butanol dehydrogenase (NAD+) activity?
Genes include adhE2 from Clostridium acetobutylicum and butanol dehydrogenase genes from Thermotoga maritima, Fusobacterium nucleatum, Enterobacter sp. VKGH12, and others.
What is the reaction catalyzed by GO:1990362?
The reaction is butan-1-ol + NAD+ = butanal + H+ + NADH, a reversible oxidation-reduction.
Which organisms have butanol dehydrogenase (NAD+) activity?
It has been characterized in bacteria such as Thermotoga maritima, Fusobacterium nucleatum, Enterobacter sp. VKGH12, Pseudomonas butanovora, Pectobacterium atrosepticum, and Clostridium acetobutylicum, as well as fungi like Fusarium merismoides.
How is butanol dehydrogenase activity measured?
It is typically measured by monitoring NADH formation at 340 nm using butan-1-ol and NAD+ as substrates.
What is the difference between NAD-dependent and quinohaemoprotein butanol dehydrogenases?
NAD-dependent enzymes use NAD+ as the electron acceptor, while quinohaemoprotein enzymes such as the Pseudomonas butanovora 1-butanol dehydrogenase use pyrroloquinoline quinone and a haem cofactor.
Is butanol dehydrogenase (NAD+) activity linked to human disease?
No direct human disease association has been reported for this exact microbial and fungal activity in the cited literature; it is primarily studied in microbial metabolism and biotechnology.
How can CRISPR be used to study butanol dehydrogenase?
CRISPR knockout, point mutation, knock-in, and overexpression can be used to test the function of butanol dehydrogenase genes in native and heterologous hosts.
What is the role of adhE2 in butanol production?
adhE2 encodes a bifunctional aldehyde/alcohol dehydrogenase responsible for butanol production in alcohologenic cultures of Clostridium acetobutylicum.
Why is butanol dehydrogenase important for biotechnology?
It is central to microbial butanol production and degradation, making it a target for engineering biofuel-producing strains and bioremediation strategies.
Conclusion
GO:1990362 butanol dehydrogenase (NAD+) activity defines a reversible NAD-dependent oxidoreduction that is central to microbial butanol metabolism. Structural and biochemical studies across diverse organisms have revealed conserved and divergent features of this enzyme family, while genetic studies in Clostridium acetobutylicum and Thermoanaerobacter mathranii have linked the activity to solvent production and biofuel pathways. CRISPR-based models offer powerful tools to dissect the function of butanol dehydrogenases and to engineer improved strains for industrial applications.
References
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- 2. Bai X et al.. 2023. Structural and Biochemical Analyses of the Butanol Dehydrogenase from Fusobacterium nucleatum.. Int J Mol Sci 24(3) PMID: 36769315
- 3. Veeranagouda Y et al.. 2008. Purification and characterization of NAD-dependent n-butanol dehydrogenase from solvent-tolerant n-butanol-degrading Enterobacter sp. VKGH12.. J Microbiol Biotechnol 18(4):663-9 PMID: 18467858
- 4. Vangnai AS et al.. 2001. An inducible 1-butanol dehydrogenase, a quinohaemoprotein, is involved in the oxidation of butane by "Pseudomonas butanovora".. Microbiology (Reading) 147(Pt 3):745-756 PMID: 11238982
- 5. Fujimitsu H et al.. 2016. Purification and characterization of 4-N-trimethylamino-1-butanol dehydrogenase from Fusarium merismoides var. acetilereum.. Biosci Biotechnol Biochem 80(9):1753-8 PMID: 27121905
- 6. Elleuche S et al.. 2014. Group III alcohol dehydrogenase from Pectobacterium atrosepticum: insights into enzymatic activity and organization of the metal ion-containing region.. Appl Microbiol Biotechnol 98(9):4041-51 PMID: 24265029
- 7. Fontaine L et al.. 2002. Molecular characterization and transcriptional analysis of adhE2, the gene encoding the NADH-dependent aldehyde/alcohol dehydrogenase responsible for butanol production in alcohologenic cultures of Clostridium acetobutylicum ATCC 824.. J Bacteriol 184(3):821-30 PMID: 11790753
- 8. Yao S et al.. 2010. Identification and overexpression of a bifunctional aldehyde/alcohol dehydrogenase responsible for ethanol production in Thermoanaerobacter mathranii.. J Mol Microbiol Biotechnol 19(3):123-33 PMID: 20924198
