Recombinant Human GAPDHS Protein: FAQs & Technical Guide

Recombinant Human GAPDHS Protein is a sperm-specific glycolytic enzyme produced recombinantly for use in biochemical, reproductive biology, and drug-discovery research applications.

Product Name

Recombinant Human GAPDHS Protein

SKU

rp367923

Gene / Protein

GAPDHS (Glyceraldehyde-3-Phosphate Dehydrogenase, Spermatogenic)

Primary Application

Biochemical assays, enzyme activity studies, reproductive biology research

Expression Origin

Recombinant (specific host system details: see product datasheet)

Storage Recommendation

Avoid repeated freeze-thaw cycles; refer to product datasheet for specific conditions

What Is GAPDHS and Why Is It Important in Research?

GAPDHS (Glyceraldehyde-3-Phosphate Dehydrogenase, Spermatogenic) is a sperm-specific isoform of the classical glycolytic enzyme GAPDH. Unlike the ubiquitously expressed GAPDH, GAPDHS expression is restricted to spermatogenic cells and mature spermatozoa, where it is tightly bound to the fibrous sheath of the sperm flagellum. GAPDHS catalyzes the conversion of glyceraldehyde-3-phosphate to 1,3-bisphosphoglycerate in the glycolytic pathway, supplying ATP locally along the flagellum to support sperm motility.

Its tissue-restricted expression makes GAPDHS a compelling target for male contraceptive drug development and a useful biomarker in studies of male infertility. Researchers also utilize recombinant GAPDHS protein to investigate enzyme kinetics, protein–protein interactions, and inhibitor screening in a defined, cell-free system.

Key Specifications of Recombinant Human GAPDHS Protein (rp367923)

Aladdin Scientific's Recombinant Human GAPDHS Protein (SKU: rp367923) is produced using recombinant expression technology. Detailed specifications including molecular weight, purity grade, formulation buffer, and endotoxin levels are provided in the product datasheet available on the product page. Researchers should consult the datasheet before designing experiments to ensure the protein format is compatible with their assay conditions.

Key parameters to verify in the datasheet include: expression host system, tag information (if any), purity (typically assessed by SDS-PAGE), biological activity confirmation, and recommended reconstitution buffer. Contact Aladdin Scientific technical support if you require lot-specific certificates of analysis.

Reconstitution, Handling, and Storage Best Practices

Proper handling of recombinant proteins is critical to preserving enzymatic activity and structural integrity. Upon receipt, briefly centrifuge the vial before opening to consolidate any lyophilized material or liquid at the bottom. Reconstitute the protein according to the instructions in the datasheet, typically using sterile, nuclease-free water or the recommended buffer.

To maintain activity: (1) Prepare single-use aliquots immediately after reconstitution to avoid repeated freeze-thaw cycles, which can significantly reduce enzymatic activity. (2) Store aliquots at the temperature specified in the datasheet (commonly −20 °C or −80 °C for long-term storage). (3) Add a carrier protein such as BSA if long-term dilute storage is required, as specified in the datasheet. Always keep samples on ice during experimental setup.

Experimental Applications and Assay Compatibility

Recombinant Human GAPDHS Protein is suitable for several research applications, including but not limited to: enzyme kinetics and activity assays measuring NAD⁺-dependent oxidoreductase activity; inhibitor and small-molecule screening programs targeting male fertility pathways; Western blot positive controls; and protein interaction studies (e.g., co-immunoprecipitation or pull-down assays) to identify GAPDHS-binding partners in the flagellar glycolytic metabolon.

Researchers developing functional assays should validate assay conditions empirically, including substrate concentrations, cofactor (NAD⁺) concentrations, buffer pH, and temperature, since recombinant protein behavior may differ from that observed in native sperm lysates. Always include appropriate positive and negative controls.

Ordering, Quality, and Technical Support

Recombinant Human GAPDHS Protein is available from Aladdin Scientific under SKU rp367923. To place an order, visit the Aladdin Scientific website, locate the product by SKU or name, and follow the standard checkout process. Bulk or custom quantities may be available upon request — contact the sales team for a quote.

Each lot is manufactured under quality-controlled conditions. A Certificate of Analysis (CoA) is available for each production lot and can be requested through customer service or downloaded from the product page. For technical questions regarding experimental design, assay optimization, or compatibility, contact Aladdin Scientific's technical support team, referencing the product SKU rp367923 and lot number for faster assistance.

Frequently asked questions

What is the difference between GAPDHS and GAPDH?

GAPDH is a ubiquitously expressed glycolytic enzyme found in virtually all cell types, whereas GAPDHS is a paralogous isoform whose expression is restricted to spermatogenic cells and mature spermatozoa. GAPDHS contains an additional proline-rich N-terminal domain that anchors it to the fibrous sheath of the sperm flagellum, enabling localized ATP production to drive sperm motility. This tissue specificity makes GAPDHS a target of interest for male contraceptive research.

How should I reconstitute and store Recombinant Human GAPDHS Protein (rp367923)?

Reconstitute the protein according to the specific instructions in the product datasheet, typically using sterile water or the recommended buffer. Immediately after reconstitution, divide the protein into single-use aliquots and store them at the temperature indicated in the datasheet (usually −20 °C or −80 °C) to avoid activity loss from repeated freeze-thaw cycles. Keep samples on ice during all handling steps.

Is Recombinant Human GAPDHS Protein suitable for inhibitor screening assays?

Yes, Recombinant Human GAPDHS Protein is suitable for biochemical inhibitor screening assays targeting GAPDHS enzymatic activity, which is relevant to male contraceptive drug discovery. Researchers should optimize assay conditions—including NAD⁺ and substrate concentrations, buffer composition, and pH—empirically before running compound libraries. Consult the product datasheet for confirmed activity data and contact Aladdin Scientific technical support for application-specific guidance.

Can I use Recombinant Human GAPDHS Protein as a Western blot positive control?

Yes, recombinant GAPDHS protein can serve as a positive control in Western blot experiments when using anti-GAPDHS antibodies, provided the antibody recognizes the recombinant form (which may carry an affinity tag). Verify antibody compatibility with the specific form of rp367923 (tag presence, denatured vs. native) by consulting the datasheet before use.

How do I request a Certificate of Analysis (CoA) for rp367923?

A Certificate of Analysis for Recombinant Human GAPDHS Protein (rp367923) can be requested through Aladdin Scientific's customer service team or may be available for download on the product page. Please have your lot number ready when contacting customer service to ensure you receive the correct batch-specific document.

References

1. Miki K et al. Targeted disruption of the Akap4 gene causes defects in sperm flagellum and motility. Dev Biol. 2002. [General reference for flagellar sheath context — GAPDHS association with fibrous sheath is textbook knowledge; specific citation needs verification]
2. Bunch DO et al. Glyceraldehyde 3-phosphate dehydrogenase-S protein distribution sheds light on sperm capacitation. Biol Reprod. 1998. [Textbook-level reference for GAPDHS localization — specific citation details need verification]
3. Aladdin Scientific. Recombinant Human GAPDHS Protein, SKU rp367923. Product Datasheet. Aladdin Scientific.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.