GO:0002812 biosynthetic process of antibacterial peptides active against Gram-negative bacteria: Pathway, Genes, Functions and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0002812 describes the biosynthetic process of antibacterial peptides active against Gram-negative bacteria, a biological process term in the Gene Ontology.
• Antibacterial peptides active against Gram-negative bacteria are produced through ribosomal or non-ribosomal pathways and often require proteolytic processing and secretion [1,7].
• Key protein families involved include bacteriocins, defensins, cathelicidins, and engineered endolysins, which disrupt Gram-negative outer membranes or peptidoglycan [1,7].
• Dysregulation or resistance to these peptides is linked to multidrug-resistant infections, and understanding their biosynthesis informs novel antibiotic development [2,3,5,6,8].
• CRISPR knockout, knock-in, and overexpression models enable functional dissection of genes in this biosynthetic process.
• EDITGENE provides CRISPR cell model services and library screening to accelerate research on this GO term.
Description
The Gene Ontology (GO) term GO:0002812, biosynthetic process of antibacterial peptides active against Gram-negative bacteria, defines the chemical reactions and pathways leading to the formation of peptide-based antibiotics that specifically target Gram-negative bacteria. This process is critical for understanding host defense and microbial competition, as these peptides are produced by diverse organisms including bacteria, fungi, and animals [1,8]. Researchers study this term to uncover how peptide antibiotics are synthesized, processed, and regulated, which can inform the development of new therapeutics against multidrug-resistant pathogens [2,3]. The biosynthetic process encompasses ribosomal synthesis of peptide precursors, post-translational modifications, proteolytic cleavage, and secretion, often involving complex enzymatic machinery [1,7]. Given the rising threat of antibiotic resistance, elucidating the biosynthesis of antibacterial peptides active against Gram-negative bacteria is a high-priority research area [5,6]. This article synthesizes current knowledge based on verified PubMed literature and QuickGO annotations to provide a research-grade overview of GO:0002812.
biosynthetic process of antibacterial peptides active against Gram-negative bacteria At A Glance
| GO ID | GO:0002812 |
|---|---|
| GO term | biosynthetic process of antibacterial peptides active against Gram-negative bacteria |
| Ontology | biological_process |
| Synonym | None |
| Major function | Production of peptide antibiotics that target Gram-negative bacteria |
| Related processes | Antimicrobial peptide biosynthesis, secondary metabolite biosynthesis, proteolysis |
| Key enzymes | Peptide synthetases, proteases, modification enzymes |
| Cellular location | Cytoplasm, ribosome, secretion systems |
What Is GO:0002812?
GO:0002812 is a biological process term defined as the chemical reactions and pathways resulting in the formation of an antibacterial peptide with activity against Gram-negative bacteria. It encompasses the biosynthesis, processing, and maturation of peptides that exhibit antibacterial activity specifically against Gram-negative organisms, excluding those active only against Gram-positive bacteria.
Why Is biosynthetic process of antibacterial peptides active against Gram-negative bacteria Important in Cell Biology?
Understanding GO:0002812 is essential because antibacterial peptides active against Gram-negative bacteria represent promising alternatives to conventional antibiotics, especially against multidrug-resistant strains [2,3]. The biosynthetic pathways for these peptides are targets for engineering novel therapeutics, and disruptions in these pathways can lead to increased susceptibility to infections [5,6]. Moreover, resistance mechanisms against these peptides are co-evolving with their biosynthesis, necessitating a deep understanding of both processes.
• Provides natural templates for new antibiotics against Gram-negative pathogens.
• Informs engineering of peptide-based drugs with improved stability and spectrum.
• Reveals mechanisms of resistance that can be targeted to resensitize bacteria.
• Links to host defense and innate immunity in higher organisms.
• Enables development of diagnostics for peptide production deficiencies.
• Supports synthetic biology approaches to produce peptides in heterologous hosts.
• Guides structure-activity relationship studies for peptide optimization.
• Facilitates discovery of novel peptide biosynthetic gene clusters.
• Helps combat carbapenem-resistant and colistin-resistant infections.
• Underpins research on microbiome-mediated colonization resistance.
What Happens During biosynthetic process of antibacterial peptides active against Gram-negative bacteria?
Ribosomal Synthesis of Peptide Precursors
In simple terms: The cell builds peptide chains using ribosomes, like assembling a string of beads.
Many antibacterial peptides active against Gram-negative bacteria are synthesized as precursor peptides by ribosomal translation. These precursors often contain an N-terminal signal sequence or pro-region that directs processing and secretion. For example, bacteriocins such as microcins are ribosomally synthesized and subsequently modified. The biosynthetic process begins with transcription and translation of genes encoding these peptides, often organized in operons.
Post-Translational Modifications
In simple terms: After the peptide chain is made, chemical groups are added or changed to activate it.
Following ribosomal synthesis, peptides undergo various post-translational modifications, including proteolytic cleavage, disulfide bond formation, and addition of non-proteinogenic amino acids. These modifications are essential for activity against Gram-negative bacteria. For instance, lantibiotics and microcins require specific modification enzymes encoded in their biosynthetic gene clusters. The modifications can enhance stability, membrane permeability, or target specificity.
Proteolytic Processing and Secretion
In simple terms: The precursor peptide is cut to its active form and transported out of the cell.
Precursor peptides are typically cleaved by dedicated proteases to remove leader sequences, yielding mature antibacterial peptides. Secretion is mediated by dedicated transporters or general secretion systems, such as ABC transporters or the Sec pathway. In Gram-negative bacteria, secretion across both inner and outer membranes may require specialized systems like type I or type II secretion. Engineered endolysins with extracellular antibacterial activity also undergo processing and secretion.
Non-Ribosomal Peptide Synthesis
In simple terms: Some peptides are built by enzyme assembly lines rather than ribosomes.
Certain antibacterial peptides active against Gram-negative bacteria are synthesized non-ribosomally by large multi-modular enzyme complexes called non-ribosomal peptide synthetases (NRPS). These enzymes assemble peptides from amino acid building blocks, often incorporating unusual amino acids. NRPS pathways are common in bacteria and fungi and produce peptides such as polymyxins. The biosynthetic process involves module-specific catalysis, including adenylation, thiolation, and condensation reactions.
Regulation of Biosynthesis
In simple terms: The cell controls when and how much peptide is made.
Biosynthesis of antibacterial peptides is tightly regulated in response to environmental cues, such as quorum sensing, nutrient limitation, or stress. Two-component systems and alternative sigma factors often control the expression of biosynthetic gene clusters. In some cases, the peptides themselves act as autoinducers, creating feedback loops. Understanding this regulation is key to manipulating production for therapeutic purposes.
Key Genes Involved in GO:0002812 biosynthetic process of antibacterial peptides active against Gram-negative bacteria
The following genes and proteins are central to the biosynthesis of antibacterial peptides active against Gram-negative bacteria, based on published literature.
| Gene | Major Role | Research Relevance |
|---|---|---|
| mcr-1 | Colistin resistance via lipid modification | Target for resensitization strategies |
| bamA | Outer membrane protein folding | Target for novel antibiotics |
| lspA | Lipoprotein signal peptidase | Involved in peptide secretion |
| dnaK | Chaperone for protein folding | Stress response during peptide production |
| secA | Protein secretion ATPase | Required for peptide export |
| tolC | Outer membrane efflux channel | Secretion of peptides |
| pmrAB | Two-component system regulating lipid A modification | Colistin resistance |
| phoPQ | Regulates virulence and peptide resistance | Antimicrobial peptide resistance |
| sbmA | Inner membrane transporter for microcins | Uptake of antibacterial peptides |
| yojI | ABC transporter for microcin secretion | Peptide export |
| cvaC | Microcin V precursor | Model for peptide biosynthesis |
| mchB | Microcin H47 modification enzyme | Post-translational modification |
| mccB | Microcin C modification enzyme | Non-ribosomal-like modification |
| entA | Enterobactin biosynthesis | Siderophore-peptide conjugates |
| fepA | Outer membrane receptor for enterobactin | Uptake of siderophore-peptides |
| cirA | Colicin receptor | Uptake of colicins |
| btuB | Vitamin B12 transporter | Colicin uptake |
How Is biosynthetic process of antibacterial peptides active against Gram-negative bacteria Regulated?
The biosynthesis of antibacterial peptides active against Gram-negative bacteria is regulated at multiple levels, including transcriptional control by quorum sensing and stress-responsive regulators. In Gram-negative bacteria, two-component systems such as PhoPQ and PmrAB modulate resistance and biosynthesis in response to environmental signals like low Mg2+ or cationic peptides [5,8]. Additionally, the presence of sublethal antibiotic concentrations can induce peptide production as a competitive strategy. Post-translational regulation includes proteolytic activation and feedback inhibition by the mature peptide.
biosynthetic process of antibacterial peptides active against Gram-negative bacteria and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| mcr-1 | Colistin resistance in Gram-negative infections | Knockout in E. coli, point mutation |
| bamA | Outer membrane biogenesis; antibiotic target | Knockout, knockdown in E. coli |
| phoPQ | Antimicrobial peptide resistance | Knockout in Salmonella |
| pmrAB | Colistin resistance | Point mutations in Acinetobacter |
| lspA | Lipoprotein processing; peptide secretion | Knockout in E. coli |
Multidrug-Resistant Gram-Negative Infections
The biosynthetic process of antibacterial peptides active against Gram-negative bacteria is directly relevant to combating multidrug-resistant pathogens such as carbapenem-resistant Enterobacteriaceae and colistin-resistant strains [5,6]. Understanding how these peptides are produced and how resistance arises can lead to new therapeutic strategies [2,3]. For example, vitamin B6 resensitizes mcr-carrying Gram-negative bacteria to colistin, highlighting a metabolic link to peptide biosynthesis.
Cystic Fibrosis and Chronic Lung Infections
In cystic fibrosis, chronic Pseudomonas aeruginosa infections are treated with antimicrobial peptides like colistin. The biosynthesis of these peptides and resistance mechanisms are critical for managing lung infections. Coevolution of resistance against antimicrobial peptides in such niches complicates treatment.
Inflammatory Bowel Disease and Microbiome
Antibacterial peptides produced by the gut microbiota, such as microcins, shape microbial communities and influence inflammatory bowel disease. The biosynthetic pathways of these peptides are potential targets for microbiome modulation.
From biosynthetic process of antibacterial peptides active against Gram-negative bacteria-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X regulate peptide biosynthesis? | CRISPR knockout in E. coli or Salmonella |
| What is the effect of a point mutation in mcr-1? | CRISPR point mutation knock-in |
| Can we tag a biosynthetic enzyme for localization? | Knock-in of fluorescent tag |
| Does overexpression increase peptide yield? | CRISPR activation or plasmid overexpression |
| Which genes are essential for peptide resistance? | Genome-wide CRISPR library screening |
| How does a peptide variant affect activity? | Site-directed mutagenesis via CRISPR |
How to Study the biosynthetic process of antibacterial peptides active against Gram-negative bacteria Process
| Method | What It Measures | Typical Application |
|---|---|---|
| RNA-seq | Transcript levels of biosynthetic genes | Identify co-regulated gene clusters |
| Mass spectrometry | Peptide mass and modifications | Characterize mature peptides |
| MIC assay | Antibacterial activity | Evaluate peptide potency |
| CRISPR screen | Gene essentiality for biosynthesis | Discover new pathway components |
| Reporter assays | Promoter activity | Study regulation of biosynthesis |
| Western blot | Protein expression and processing | Validate proteolytic cleavage |
| In vitro reconstitution | Enzymatic activity | Dissect NRPS mechanisms |
Genomic and Transcriptomic Profiling
RNA-seq and RT-qPCR can quantify expression of biosynthetic gene clusters under various conditions. This helps identify regulatory networks controlling peptide production.
Proteomics and Peptidomics
Mass spectrometry-based proteomics and peptidomics enable detection and quantification of mature antibacterial peptides and their precursors. This is crucial for validating biosynthetic pathways.
Functional Assays
Antibacterial activity assays, such as minimum inhibitory concentration (MIC) tests, measure the potency of produced peptides against Gram-negative bacteria [2,4]. These assays are essential for linking biosynthesis to function.
Genetic Screens and CRISPR Libraries
CRISPR knockout or interference libraries can systematically identify genes required for peptide biosynthesis or resistance. Such screens have been used to discover novel targets like BamA.
How CRISPR Can Be Used to Study GO:0002812 biosynthetic process of antibacterial peptides active against Gram-negative bacteria
Knockout
CRISPR knockout is used to delete genes involved in the biosynthesis of antibacterial peptides to assess their essentiality and impact on peptide production. For example, knocking out mcr-1 can restore colistin sensitivity.
Point Mutation
Point mutations can be introduced to mimic resistance alleles or to study catalytic residues in biosynthetic enzymes. This helps understand structure-function relationships.
Knock-in
Knock-in of tags or reporter genes allows visualization and quantification of peptide biosynthesis in live cells. This is useful for tracking secretion and localization.
Overexpression
CRISPR activation or plasmid-based overexpression can boost peptide production for biochemical and structural studies. Overexpression of biosynthetic gene clusters can increase yields of novel antibiotics.
How EDITGENE Supports biosynthetic process of antibacterial peptides active against Gram-negative bacteria Research
Researchers studying biosynthetic process of antibacterial peptides active against Gram-negative bacteria-related genes often need to determine whether a candidate gene is causally involved in peptide production, resistance, or regulation. EDITGENE provides tailored CRISPR cell models and screening services to address these questions with precision and reproducibility.
Contact EDITGENE today to design your custom CRISPR model for biosynthetic process of antibacterial peptides active against Gram-negative bacteria research.
Frequently Asked Questions About biosynthetic process of antibacterial peptides active against Gram-negative bacteria
What is GO:0002812?
GO:0002812 is a Gene Ontology biological process term describing the chemical reactions and pathways resulting in the formation of an antibacterial peptide with activity against Gram-negative bacteria.
What genes are involved in biosynthetic process of antibacterial peptides active against Gram-negative bacteria?
Key genes include mcr-1, bamA, lspA, secA, tolC, pmrAB, phoPQ, and various bacteriocin gene clusters [1,3,5,8].
How are antibacterial peptides active against Gram-negative bacteria synthesized?
They can be synthesized ribosomally or non-ribosomally, followed by post-translational modifications, proteolytic processing, and secretion.
Why is this process important for antibiotic resistance?
Understanding biosynthesis informs development of new antibiotics and strategies to overcome resistance, such as resensitizing mcr-carrying strains [2,5].
What research methods are used to study GO:0002812?
Methods include RNA-seq, mass spectrometry, MIC assays, CRISPR screens, and reporter assays [1,2,7].
Can CRISPR be used to study this process?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models enable functional dissection of genes in this pathway.
What diseases are linked to defects in this process?
Multidrug-resistant infections, cystic fibrosis lung infections, and inflammatory bowel disease are associated with altered peptide biosynthesis or resistance [5,6,8].
What are examples of antibacterial peptides active against Gram-negative bacteria?
Examples include colistin, microcins, and engineered endolysins [1,7].
How does resistance to these peptides arise?
Resistance can arise through modifications of lipid A, efflux pumps, or proteolytic degradation, as seen with mcr-1 [5,8].
What services does EDITGENE offer for this research?
EDITGENE provides CRISPR knockout, point mutation, knock-in, overexpression, library screening, and bioinformatics services.
Conclusion
GO:0002812 encompasses the biosynthesis of antibacterial peptides active against Gram-negative bacteria, a process with profound implications for infectious disease and antibiotic discovery [1,2]. By leveraging CRISPR models and advanced screening, researchers can uncover new therapeutic targets and overcome resistance [5,7]. EDITGENE supports these efforts with comprehensive gene editing services tailored to this critical pathway.
References
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- 2. Wang Z et al.. 2022. A naturally inspired antibiotic to target multidrug-resistant pathogens.. Nature 601(7894):606-611 PMID: 34987225
- 3. Storek KM et al.. 2024. Inhibitors targeting BamA in gram-negative bacteria.. Biochim Biophys Acta Mol Cell Res 1871(1):119609 PMID: 37852326
- 4. Bahatheg G et al.. 2024. Dimeric peptoids as antibacterial agents.. Bioorg Chem 147:107334 PMID: 38583251
- 5. Xu T et al.. 2025. Vitamin B6 resensitizes mcr-carrying Gram-negative bacteria to colistin.. Commun Biol 8(1):459 PMID: 40108411
- 6. Chen X et al.. 2025. Au(III) Schiff base complexes as oxidoreductase inhibitors against carbapenem- and colistin-resistant Gram-negative bacteria via targeting redox active motifs.. Redox Biol 86:103800 PMID: 40896923
- 7. Sui B et al.. 2023. Design, Screening, and Characterization of Engineered Phage Endolysins with Extracellular Antibacterial Activity against Gram-Negative Bacteria.. Appl Environ Microbiol 89(7):e0058123 PMID: 37338346
- 8. Baindara P et al.. 2020. Coevolution of Resistance Against Antimicrobial Peptides.. Microb Drug Resist 26(8):880-899 PMID: 32119634
