GT01 was engineered by introducing eight amino acid mutations and inserting four residues into the SBTI scaffold. Key features include:
Binding loops: Two grafted peptide loops (GDR1/2) enable specific recognition of the GTD domain .
Disulfide bonds: Retains three native disulfide bonds for stability under denaturing conditions .
Thermostability: Melting temperature (T<sub>m</sub>) of 59°C, comparable to wild-type SBTI (T<sub>m</sub> = 63°C) .
| Target | Binding Observed? | Cross-reactivity |
|---|---|---|
| GTD (TcdB) | Yes | None |
| Trypsin | Yes (via R63) | Eliminated in R63A mutant |
| CROP/BLA/HEL | No | N/A |
GT01 inhibits GTD’s enzymatic activity in a dose-dependent manner:
Cytoskeletal protection: Prevents TcdB-induced disruption of epithelial barriers by neutralizing GTD .
| GT01 Concentration (nM) | % Inhibition of GTD Activity |
|---|---|
| 0 | 0 |
| 50 | 25 |
| 100 | 50 |
| 200 | 75 |
GT01 exhibits exceptional resilience:
Protease resistance: Resists pepsin, chymotrypsin, and elastase digestion at pH 2.0–7.4 .
Thermal stability: Retains 90% functionality after 10 minutes at 55°C .
| Protease | Cleavage Observed? | Notes |
|---|---|---|
| Pepsin | No | Intact GT01 domain |
| Chymotrypsin | No | N-terminal tag cleavage only |
| Trypsin | Partial | Scissile Arg (R63) cleavage in wild-type |
KEGG: sce:YGR154C
STRING: 4932.YGR154C
GOT1 (glutamic-oxaloacetic transaminase 1) is a cytoplasmic enzyme that catalyzes the reversible reaction of L-aspartate and alpha-ketoglutarate into oxaloacetate and L-glutamate, playing a key role in carbon and nitrogen metabolism. GOT1 can potentially control the intracellular levels of reactive oxygen species (ROS) through NADPH synthesis and is critical to the survival of cells with electron transport chain inhibition by generating aspartate, a metabolite determining cell proliferation .
Anti-GOT1 antibodies are valuable research tools for:
Studying metabolic pathways in normal and diseased states
Investigating cellular stress responses
Examining liver function and pathology
Researching cancer metabolism, particularly in liver tumorigenesis
Selection of an appropriate GOT1 antibody requires consideration of several experimental factors:
| Application | Recommended Antibody Type | Dilution Range | Validation Methods |
|---|---|---|---|
| Western Blot (WB) | Monoclonal or polyclonal | 1:500-1:2000 | KO cell lines, positive controls (HepG2, L02, mouse/rat brain) |
| Immunoprecipitation (IP) | Polyclonal preferred | 0.5-4.0 μg for 1-3 mg protein | Mouse brain tissue as positive control |
| Immunofluorescence (IF) | Monoclonal or polyclonal | 1:50-1:500 | L02 cells as positive control |
Recommendations based on reactivity needs:
For human samples only: Most commercial antibodies are suitable
For cross-species studies: Choose antibodies with verified reactivity across target species
For specific cellular compartments: Select antibodies validated for the particular subcellular localization
Always check validation data and published literature using the specific clone/catalog number for your applications of interest.
Proper validation of GOT1 antibodies is critical for research reproducibility. The gold standard approaches include:
Essential validation methods:
Knockout (KO) cell line testing: This is considered the superior control method for Western blots and immunofluorescence imaging. Compare signal between wild-type cells and GOT1 knockout cells .
Overexpression validation: Transfect cells with GOT1 expression vector and verify signal increase compared to control cells.
Multiple antibody concordance: Use at least two antibodies targeting different epitopes of GOT1 and check for signal correlation.
Additional controls:
Peptide competition assay: Pre-incubate the antibody with immunizing peptide before staining.
Signal correlation with established protein expression patterns: GOT1 is highly expressed in liver and brain tissues.
Recent large-scale antibody characterization studies found that approximately 50-75% of commercial antibodies demonstrate specific binding to their target proteins, highlighting the importance of rigorous validation .
Optimizing Western blot protocols for GOT1 detection requires attention to several key parameters:
Sample preparation:
Use RIPA buffer with protease inhibitors for tissue/cell lysis
For brain tissue samples (high GOT1 expression), dilute samples more than liver samples
Include phosphatase inhibitors if studying post-translational modifications
Electrophoresis and transfer conditions:
Load 20-40 μg of total protein per lane
Use 10-12% polyacrylamide gels for optimal resolution
Transfer at low voltage (30V) overnight at 4°C for better transfer efficiency
Antibody incubation:
Primary antibody: Start with 1:1000 dilution (adjust based on signal strength)
Recommended blocking: 5% non-fat milk in TBST for 1 hour at room temperature
Positive controls:
Troubleshooting tip: If experiencing high background, try increasing washing steps or reducing antibody concentration.
GOT1 antibodies have become valuable tools for studying metabolic reprogramming in cancer research, particularly for understanding the noncanonical glutamine pathway that supports tumorigenesis:
Experimental approaches using GOT1 antibodies:
Immunohistochemical profiling: Use IHC to compare GOT1 expression levels between normal and cancerous tissues. This reveals upregulation patterns in specific cancer types, particularly hepatocellular carcinoma.
Co-immunoprecipitation studies: Use GOT1 antibodies for co-IP experiments to identify protein interaction partners in the aspartate biosynthesis pathway, revealing cancer-specific metabolic networks.
ChIP assays: When combined with chromatin immunoprecipitation, GOT1 antibodies can help identify transcription factors regulating GOT1 expression in different cancer states.
Metabolic flux analysis: Use GOT1 antibodies in conjunction with knockout/knockdown studies to quantify changes in metabolite levels when GOT1 is inhibited, particularly aspartate production.
Recent studies have shown that GOT1 plays a key role in the noncanonical glutamine pathway that supports liver tumorigenesis, making it an important potential therapeutic target .
When designing multiplex experiments using GOT1 antibodies alongside other metabolic enzyme antibodies, several important considerations must be addressed:
Technical considerations:
Antibody cross-reactivity: Verify that antibodies against GOT1 do not cross-react with the highly homologous GOT2 (mitochondrial isoform). Specificity testing against both isoforms is essential.
Species compatibility: When using multiple antibodies raised in different host species, ensure secondary antibodies are highly specific to avoid false co-localization signals.
Signal separation in multiplex imaging: For co-localization studies with other metabolic enzymes, select fluorophores with minimal spectral overlap and use proper controls for bleed-through.
Experimental design considerations:
Pathway analysis: Include antibodies against enzymes directly interacting with GOT1 in the malate-aspartate shuttle (MDH1, MDH2) to get a comprehensive view of metabolic flux.
Subcellular localization: When studying metabolic compartmentalization, combine GOT1 antibodies with markers for different cellular compartments (ER, mitochondria, etc.).
Stimulation conditions: Consider how different metabolic states affect the expression and localization of multiple metabolic enzymes simultaneously. Design time-course experiments accordingly.
Researchers frequently encounter specific challenges when working with GOT1 antibodies. Here are solutions to common problems:
When facing persistent issues, cross-validation with multiple detection methods is strongly recommended. If Western blot yields inconsistent results, confirm with immunofluorescence or enzymatic activity assays .
Comprehensive analysis of GOT1 expression requires integration within broader metabolic contexts:
Multi-level data integration approaches:
Expression correlation analysis:
Analyze correlations between GOT1 and related metabolic enzymes (MDH1, GOT2, etc.)
Use hierarchical clustering to identify co-regulated metabolic modules
Compare expression patterns across different tissues and disease states
Functional network analysis:
Use pathway enrichment tools (KEGG, Reactome) to position GOT1 data in canonical pathways
Implement Gaussian graphical models to infer metabolic networks from expression data
Integrate with metabolomics data to correlate enzyme levels with metabolite changes
Interpretation guidelines:
Consider GOT1/GOT2 ratios rather than absolute values alone
Account for post-translational modifications that affect enzyme activity
Remember that protein levels may not directly correlate with enzymatic activity
Visualization strategies:
Use pathway visualization tools (Cytoscape, PathVisio) to map expression data onto metabolic networks
Generate heat maps showing coordinated changes across multiple enzymes
Create correlation networks to identify key regulatory nodes
When interpreting GOT1 data, remember that its role extends beyond traditional amino acid metabolism to influence redox balance and nucleotide synthesis .
Understanding the differences between monoclonal and polyclonal GOT1 antibodies is crucial for selecting the optimal reagent:
Combining antibody-based detection with functional assays provides a more complete understanding of GOT1 biology:
Advanced protein interaction methods:
Proximity ligation assay (PLA):
Uses pairs of antibodies against GOT1 and potential interaction partners
Produces fluorescent signal only when proteins are in close proximity (<40 nm)
Enables visualization of interactions in their native cellular context
Requires careful antibody validation to eliminate false positives
FRET/BRET assays with antibody targeting:
Combine fluorescently-labeled anti-GOT1 antibody fragments with tagged potential interaction partners
Allows real-time monitoring of dynamic interactions
Requires specialized equipment and careful controls
Enzyme activity correlation methods:
In-gel activity assays with subsequent immunoblotting:
Run native protein samples on non-denaturing gels
Perform activity staining using GOT1 substrates and cofactors
Transfer and immunoblot with anti-GOT1 antibodies
Allows correlation between activity and protein amount/modifications
Immunocapture enzyme assays:
Immobilize anti-GOT1 antibodies on solid support
Capture GOT1 from lysates
Perform enzyme activity measurements directly on captured protein
Compare activity to protein amount by elution and immunoblotting
Single-cell correlation of enzyme activity and expression:
Use fluorescent GOT1 substrate analogs to measure activity in living cells
Fix and stain with anti-GOT1 antibodies
Analyze correlation between activity and expression at single-cell level
Reveals potential post-translational regulation mechanisms
These advanced techniques help bridge the gap between GOT1 protein detection and its functional significance in metabolic pathways .
Recent technological advances have significantly improved GOT1 antibody characterization and reliability:
Emerging technologies and methodologies:
CRISPR-Cas9 knockout validation:
The use of knockout cell lines has become the gold standard for antibody validation
YCharOS initiative has demonstrated that KO cell lines are superior controls for Western blots and immunofluorescence imaging
Approximately 50-75% of commercial antibodies demonstrated specific binding when tested against KO controls
Recombinant antibody development:
Standardized validation protocols:
Open science initiatives:
These advances are transforming GOT1 antibody research by increasing reliability, reducing wastage of research resources, and improving data reproducibility across laboratories.
As single-cell technologies and spatial proteomics advance, researchers need specific considerations when using GOT1 antibodies in these cutting-edge applications:
Single-cell proteomics considerations:
Antibody specificity requirements:
Higher specificity demands due to lower target abundance in single cells
Validation using orthogonal methods becomes more critical
Clone selection should prioritize antibodies with minimal background staining
Signal amplification strategies:
Consider tyramide signal amplification for immunofluorescence applications
Evaluate proximity extension assays for digital protein counting
Balance signal enhancement with potential increase in background
Multiplexing compatibility:
Verify antibody performance in multiplexed formats (CyTOF, CODEX, etc.)
Test for antibody cross-reactivity in highly multiplexed panels
Consider clone isotypes for compatibility with multiplexing strategies
Spatial proteomics applications:
Tissue preparation compatibility:
Validate antibody performance across different fixation methods
Determine epitope sensitivity to common antigen retrieval techniques
Test compatibility with tissue clearing methods for 3D imaging
Resolution considerations:
Evaluate antibody performance at subcellular resolution
Test specificity in tissue regions with varying GOT1 expression levels
Verify for specific tissue/cell type artifacts
Data analysis approaches:
Develop robust image analysis pipelines for quantification
Implement computational methods to correct for tissue autofluorescence
Consider machine learning approaches for pattern recognition in spatial data
When pioneering these advanced applications, researchers should implement rigorous controls and validation experiments specific to each new technology platform .