PYRD Antibody

What is PYRD Antibody and what specific protein does it target?

PYRD Antibody typically refers to antibodies targeting dihydroorotate dehydrogenase (DHODH), a critical enzyme in the de novo pyrimidine biosynthesis pathway. This enzyme catalyzes the conversion of dihydroorotate to orotate, which is essential for nucleic acid production. The antibody recognizes specific epitopes on the DHODH protein, allowing for detection in various experimental contexts. The molecular weight of the target protein is approximately 43 kDa, as confirmed through Western blot analysis . The antibody has demonstrated reactivity with human, mouse, and rat samples, making it versatile for comparative studies across species .

What are the primary applications of PYRD Antibody in research settings?

PYRD Antibody has been validated for multiple experimental applications, with specific recommended dilutions for each:

These applications make PYRD Antibody valuable for studying enzyme expression patterns, protein-protein interactions, and subcellular localization in various experimental contexts . The antibody has been successfully used in multiple tissue types including heart, ovary, spleen, and kidney tissues, as well as various cell lines including A2780, MCF-7, and SKOV-3 .

How should PYRD Antibody be stored and handled to maintain optimal reactivity?

PYRD Antibody should be stored in PBS with 0.02% sodium azide and 50% glycerol at pH 7.3 to maintain stability and reactivity. For long-term storage, aliquoting and storing at -20°C to -70°C is recommended, avoiding repeated freeze-thaw cycles which can degrade antibody quality . Similar to other research antibodies like the Human Peptide YY Antibody, PYRD Antibody can typically be stored for approximately 12 months from the date of receipt at -20°C to -70°C as supplied . After reconstitution, it remains stable for approximately 1 month at 2-8°C under sterile conditions, or 6 months at -20°C to -70°C . Before each use, the antibody should be brought to room temperature gradually and centrifuged briefly to collect the solution at the bottom of the tube.

What positive and negative controls should be used when validating PYRD Antibody?

When validating PYRD Antibody specificity, appropriate positive controls include cell lines with known DHODH expression (such as A2780, MCF-7, or SKOV-3 cells) and tissue samples from mouse heart, ovary, or spleen . Negative controls should include:

• Primary antibody omission control - using only secondary antibody to detect non-specific binding

• Isotype control - using an irrelevant antibody of the same isotype to identify Fc receptor binding

• DHODH knockout or knockdown samples - providing the most stringent validation of specificity

The antibody has been validated in multiple studies using knockdown/knockout approaches, with at least 14 published studies specifically mentioning KD/KO validation techniques . Similar to approaches used with other antibodies in research, blocking peptide competition assays can provide additional validation of specificity, where pre-incubation of the antibody with its immunogenic peptide should abolish specific staining.

How does epitope specificity affect PYRD Antibody performance in different experimental conditions?

The epitope specificity of PYRD Antibody significantly influences its performance across experimental conditions. The antibody is raised against a specific fusion protein antigen (Ag6649), which determines its recognition capabilities . Similar to what's observed with anti-Borrelia antibodies, the pattern of antibody reactivity can vary considerably depending on the epitope recognized . Some epitopes may be more accessible in denatured conditions (Western blotting) but hidden in native conditions (immunoprecipitation), explaining why an antibody might work well in one application but not another.

In fixed tissues, antigen retrieval methods can dramatically affect epitope accessibility. For PYRD Antibody used in IHC, TE buffer at pH 9.0 is specifically recommended for optimal epitope exposure, although citrate buffer at pH 6.0 can serve as an alternative . This pH-dependent variation in epitope recognition demonstrates the importance of understanding how fixation and retrieval methods interact with specific antibody binding sites. Researchers should systematically test different retrieval methods when applying PYRD Antibody to new experimental systems.

What are the key considerations when using PYRD Antibody for studying DHODH's role in cancer metabolism?

When investigating DHODH's role in cancer metabolism using PYRD Antibody, researchers should consider several critical factors:

• Cancer-specific expression patterns: DHODH expression varies significantly across cancer types. The antibody has been validated in several cancer cell lines including A2780, MCF-7, and SKOV-3 , but expression levels should be quantified for each new cancer model.

• Subcellular localization: DHODH is primarily localized to the inner mitochondrial membrane. When using immunofluorescence, co-staining with mitochondrial markers is essential to confirm proper localization and antibody specificity.

• Functional correlation: Recent research indicates "DHODH-mediated ferroptosis defence is a targetable vulnerability in cancer" . When studying this pathway, researchers should correlate antibody-based detection of DHODH with functional assays of ferroptosis susceptibility.

• Drug treatment effects: If studying DHODH inhibitors, researchers should monitor changes in DHODH expression, localization, and post-translational modifications using the antibody before and after treatment.

• Heterogeneity considerations: Single-cell techniques (like flow cytometry with PYRD Antibody) may reveal important heterogeneity in DHODH expression within tumors that bulk analyses would miss.

How can PYRD Antibody be used effectively in multiplex immunoassays with other antibodies?

Effective multiplex immunoassays with PYRD Antibody require careful consideration of several technical parameters:

• Antibody species compatibility: Since PYRD Antibody is rabbit-derived (IgG) , it should be paired with antibodies from different host species (mouse, goat, etc.) to avoid cross-reactivity of secondary antibodies.

• Fluorophore selection: For immunofluorescence applications, select fluorophores with minimal spectral overlap when designing multiplex panels. Consider the excitation/emission spectra of each fluorophore and the capabilities of your imaging system.

• Fixation protocol standardization: All antibodies in the multiplex panel must perform optimally under the same fixation conditions. Test each antibody individually before combining them.

• Sequential staining approach: For challenging combinations, consider sequential staining with complete washing and blocking steps between antibodies, particularly if using multiple rabbit-derived antibodies with different detection systems.

• Cross-blocking verification: Similar to techniques used in anti-PfRH5 antibody studies , verify that PYRD Antibody doesn't cross-block or interfere with the binding of other antibodies in your panel through systematic testing.

What are the potential pitfalls when using PYRD Antibody for quantitative analysis of DHODH expression?

When using PYRD Antibody for quantitative analysis of DHODH expression, researchers should be aware of several potential pitfalls:

• Antibody saturation effects: At very high antigen concentrations, signal may plateau due to antibody saturation. Researchers should establish a standard curve using recombinant DHODH protein to define the linear range of detection, similar to the approach demonstrated with Human Peptide YY ELISA standard curves .

• Batch-to-batch variability: Polyclonal antibodies like PYRD Antibody (14877-1-AP) may show batch-to-batch variation. Critical quantitative experiments should use the same antibody lot, or include internal standards to normalize between batches.

• Post-translational modifications: DHODH undergoes post-translational modifications that may affect antibody recognition. The epitope recognized by PYRD Antibody may be masked or altered by these modifications in certain physiological or pathological conditions.

• Sample preparation inconsistencies: Variations in sample preparation (protein extraction efficiency, fixation times, etc.) can significantly impact quantitative results. Standardized protocols with appropriate loading controls are essential.

• Confounding by non-specific binding: While the antibody has been affinity-purified , low levels of non-specific binding may affect quantitative accuracy, particularly in complex samples. Knockout/knockdown controls are crucial for validating specificity in each experimental system.

What optimization steps are required when using PYRD Antibody for immunohistochemistry in different tissue types?

Optimizing PYRD Antibody for immunohistochemistry across different tissue types requires systematic adjustment of several parameters:

• Antigen retrieval optimization: While TE buffer (pH 9.0) is recommended as the primary retrieval method for PYRD Antibody, alternative methods including citrate buffer (pH 6.0) should be tested systematically on each tissue type . Different tissues may require different retrieval conditions due to variations in fixation effects.

• Antibody titration: The recommended dilution range of 1:50-1:500 for IHC provides a starting point, but optimal concentration should be determined experimentally for each tissue type through serial dilution tests:

  Tissue Type	Starting Dilution	Optimal Range (Common Finding)
  Liver	1:100	1:100-1:200
  Kidney	1:100	1:100-1:300
  Brain	1:50	1:50-1:100
  Breast cancer	1:100	1:100-1:200

• Blocking optimization: Different tissues have varying levels of endogenous biotin, peroxidase, and Fc receptors that can cause background staining. Tissue-specific blocking protocols should be developed.

• Incubation conditions: Temperature and duration of primary antibody incubation may need adjustment based on tissue type and section thickness. For most tissues, overnight incubation at 4°C often provides the best signal-to-noise ratio.

• Detection system selection: For tissues with low DHODH expression, amplification systems like tyramide signal amplification may be necessary, while high-expression tissues may work well with conventional detection methods.

How can PYRD Antibody be validated for specificity in novel experimental systems?

Thorough validation of PYRD Antibody specificity in novel experimental systems should include multiple complementary approaches:

• Genetic validation: The gold standard approach involves comparing antibody staining in wildtype samples versus DHODH knockout or knockdown models. This approach has been documented in at least 14 publications utilizing this antibody .

• Peptide competition: Pre-incubating the antibody with excess immunizing peptide should abolish specific staining. This test confirms that the observed signal comes from the antibody binding to its intended epitope.

• Orthogonal detection methods: Correlation of antibody-based detection with orthogonal methods like mass spectrometry or RNA-seq data provides additional validation of specificity.

• Multiple antibody concordance: Using multiple antibodies targeting different DHODH epitopes that show concordant staining patterns increases confidence in specificity.

• Expected pattern verification: DHODH has a characteristic subcellular distribution (primarily mitochondrial). Immunofluorescence results should show co-localization with mitochondrial markers.

• Western blot validation: A single band at the expected molecular weight (43 kDa) in Western blot provides supporting evidence for specificity in your experimental system.

What are the most effective protocols for using PYRD Antibody in co-immunoprecipitation studies?

For effective co-immunoprecipitation (co-IP) studies using PYRD Antibody, consider this optimized protocol based on published approaches:

• Sample preparation:

  • Lyse cells in a gentle, non-denaturing buffer (e.g., 50 mM Tris-HCl pH 7.4, 150 mM NaCl, 1 mM EDTA, 1% Triton X-100)

  • Include protease inhibitors, phosphatase inhibitors, and 1 mM DTT

  • Clear lysate by centrifugation (14,000 × g, 10 minutes, 4°C)

• Pre-clearing (reduces non-specific binding):

  • Incubate lysate with Protein A/G beads for 1 hour at 4°C

  • Remove beads by centrifugation

• Antibody binding:

  • Use 0.5-4.0 μg of PYRD Antibody per 1.0-3.0 mg of total protein

  • Incubate overnight at 4°C with gentle rotation

• Immunoprecipitation:

  • Add pre-washed Protein A/G beads

  • Incubate 2-4 hours at 4°C with gentle rotation

  • Wash 4-5 times with lysis buffer

• Elution and analysis:

  • Elute with SDS sample buffer at 95°C for 5 minutes

  • Analyze by SDS-PAGE and Western blotting with antibodies against suspected interaction partners

• Controls:

  • Input control (5-10% of starting material)

  • IgG control (same amount of non-specific rabbit IgG)

  • Reverse IP (use antibodies against suspected interaction partners for IP, then probe for DHODH)

This protocol has been optimized based on successful IP applications of PYRD Antibody in mouse spleen tissue and can be adapted for various cell types and experimental conditions.

What is the optimal approach for using PYRD Antibody in flow cytometry for intracellular staining?

The optimal approach for intracellular staining with PYRD Antibody in flow cytometry involves the following key steps and considerations:

• Cell preparation:

  • Harvest cells using non-enzymatic methods when possible to preserve epitopes

  • Wash cells in PBS containing 0.5% BSA

  • Fix with 4% paraformaldehyde for 15 minutes at room temperature

• Permeabilization optimization:

  • Since DHODH is a mitochondrial protein, standard saponin permeabilization (0.1%) may be insufficient

  • Test both saponin (0.1-0.5%) and Triton X-100 (0.1-0.2%) permeabilization methods

  • Methanol permeabilization (-20°C, 10 minutes) may improve access to mitochondrial antigens

• Antibody concentration:

  • Use PYRD Antibody at 0.20 μg per 10^6 cells in 100 μl

  • Incubate for 30-45 minutes at room temperature in the dark

• Washing and secondary detection:

  • Wash 3× with permeabilization buffer

  • If using an unconjugated primary antibody, incubate with fluorophore-conjugated anti-rabbit secondary antibody

  • Include a final wash in PBS without detergent before analysis

• Controls:

  • Unstained cells for autofluorescence assessment

  • Secondary-only control to establish background

  • Isotype control (rabbit IgG at matching concentration)

  • Positive control (cell line with known high DHODH expression, such as HEK-293T cells)

• Gating strategy:

  • Gate on single, viable cells

  • Consider including a mitochondrial marker to confirm proper permeabilization

  • Compare to cells with known DHODH expression levels (high, low, and negative)

This approach has been successfully used for intracellular detection in HEK-293T cells and can be adapted for other cell types of interest.

How can PYRD Antibody be used to investigate the relationship between DHODH and ferroptosis in cancer cells?

To investigate the relationship between DHODH and ferroptosis using PYRD Antibody, researchers should employ a multi-faceted experimental approach:

• Expression correlation studies:

  • Use PYRD Antibody for Western blot or IHC analysis of DHODH expression in cancer cells with varying ferroptosis sensitivity

  • Correlate DHODH protein levels with ferroptosis markers (e.g., lipid peroxidation, GSH depletion)

• DHODH inhibition experiments:

  • Treat cells with DHODH inhibitors and assess:

    • Changes in DHODH protein levels and localization using PYRD Antibody

    • Alterations in ferroptosis sensitivity using cell death assays

    • Lipid peroxidation levels using C11-BODIPY or MDA assays

• Genetic manipulation validation:

  • Generate DHODH knockdown and overexpression models

  • Confirm modulation using PYRD Antibody Western blot

  • Assess impact on ferroptosis sensitivity

• Co-localization studies:

  • Use PYRD Antibody in immunofluorescence to examine co-localization of DHODH with:

    • Mitochondrial markers

    • Lipid peroxidation sensors

    • Ferroptosis regulators (GPX4, FSP1)

• Rescue experiments:

  • Induce ferroptosis with standard inducers (erastin, RSL3)

  • Test if pyrimidine supplementation rescues ferroptosis

  • Monitor DHODH expression and localization changes during rescue using PYRD Antibody

• Patient sample analysis:

  • Use PYRD Antibody to assess DHODH expression in patient-derived cancer samples

  • Correlate expression with ferroptosis markers and patient outcomes

This approach builds on the finding that "DHODH-mediated ferroptosis defence is a targetable vulnerability in cancer" and provides a comprehensive framework for exploring this relationship.

What methodological considerations are important when using PYRD Antibody for quantitative Western blotting?

Achieving reliable quantitative Western blot results with PYRD Antibody requires attention to several methodological considerations:

• Sample preparation standardization:

  • Use consistent lysis buffers and protocols

  • Determine protein concentration using a reliable method (BCA or Bradford)

  • Prepare all samples to identical protein concentrations

• Loading control selection:

  • Choose appropriate loading controls based on experimental conditions

  • For mitochondrial proteins like DHODH, consider VDAC or COX IV as loading controls

  • Verify that experimental conditions don't affect loading control expression

• Antibody dilution optimization:

  • Test a range of dilutions within the recommended 1:2000-1:16000 range

  • Establish the optimal dilution that provides signal in the linear dynamic range

  • Document the relationship between protein amount and signal intensity

• Detection system considerations:

  • Use a digital imaging system with a wide dynamic range

  • Avoid film exposure which has limited dynamic range

  • Capture multiple exposure times to ensure linearity

• Quantification approach:

  • Use software that measures integrated density rather than peak intensity

  • Subtract local background for each band

  • Normalize to loading controls

  • Include a standard curve using recombinant DHODH protein when absolute quantification is needed

• Technical replication:

  • Perform at least three independent experiments

  • Consider technical replicates within each experiment

  • Use statistical methods appropriate for ratio data

These considerations enable reliable quantification of DHODH protein levels across different experimental conditions, providing robust data for comparative studies.

What are the best practices for troubleshooting non-specific binding when using PYRD Antibody in immunohistochemistry?

When encountering non-specific binding with PYRD Antibody in immunohistochemistry, consider this systematic troubleshooting approach:

• Optimize blocking conditions:

  • Increase blocking agent concentration (5-10% normal serum)

  • Try different blocking agents (BSA, casein, commercial blocking solutions)

  • Consider dual blocking with both protein and serum

  • Extend blocking time to 1-2 hours at room temperature

• Reduce primary antibody concentration:

  • Test more dilute antibody solutions (starting from the upper end of the 1:50-1:500 recommended range)

  • Extend incubation time while reducing concentration

• Modify washing procedure:

  • Increase number and duration of washes

  • Add 0.1-0.3% Triton X-100 or Tween-20 to wash buffers

  • Consider using TBS instead of PBS if phosphate interference is suspected

• Optimize antigen retrieval:

  • Compare recommended TE buffer (pH 9.0) with citrate buffer (pH 6.0)

  • Test different retrieval times (10-30 minutes)

  • Try different retrieval methods (microwave, pressure cooker, water bath)

• Address tissue-specific issues:

  • For tissues with high endogenous peroxidase activity, enhance quenching (3% H₂O₂, 15-30 minutes)

  • For tissues with biotin, use streptavidin/biotin blocking kit

  • For tissues with high background, consider signal amplification alternatives

• Control experiments:

  • Perform antibody absorption with immunizing peptide

  • Include no-primary-antibody control

  • Test on tissues known to be negative for DHODH

This systematic approach helps identify the source of non-specific binding and optimize conditions for specific DHODH detection.

How does PYRD Antibody specificity compare to other antibodies targeting similar metabolic enzymes?

PYRD Antibody shares many characteristics with other antibodies targeting metabolic enzymes, but also has distinct properties that researchers should consider. As a polyclonal antibody raised against a specific DHODH fusion protein , it recognizes multiple epitopes, providing robust detection but potentially more background than monoclonal alternatives. This is similar to the pattern observed with other metabolic enzyme antibodies where specificity profiles can vary significantly.

The validation profile of PYRD Antibody is relatively strong, with documented performance in Western blot, immunohistochemistry, immunofluorescence, flow cytometry, and immunoprecipitation applications . This multi-application validation is comparable to well-characterized antibodies like those against PfRH5, where functional validation across multiple techniques provides confidence in specificity .