Recombinant Human HSD17B11 Protein: Preparation & Use Protocol
Recombinant Human HSD17B11 Protein: Preparation & Use Protocol
Recombinant Human HSD17B11 Protein is a research-grade enzyme preparation designed to support investigations into 17β-hydroxysteroid dehydrogenase activity, steroid metabolism, and lipid biology in biochemical and cell-based experimental systems.
- Product Name
- Recombinant Human HSD17B11 Protein
- SKU
- rp368124
- Protein Family
- Short-chain dehydrogenase/reductase (SDR) superfamily, 17β-hydroxysteroid dehydrogenase type 11
- Species Origin
- Human (Homo sapiens)
- Application Areas
- Steroid metabolism studies, lipid biology, enzyme activity assays, biochemical research
- Storage Recommendation
- Avoid repeated freeze-thaw cycles; store as single-use aliquots at -80 °C for long-term storage
Materials Required
Before beginning this protocol, ensure the following materials are available in your laboratory:
- Recombinant Human HSD17B11 Protein (SKU: rp368124, Aladdin Scientific)
- Appropriate reconstitution buffer (e.g., sterile phosphate-buffered saline, pH 7.4, containing a carrier protein such as 0.1% BSA if recommended on the Certificate of Analysis)
- Microcentrifuge tubes (low-protein-binding, 1.5 mL)
- Calibrated micropipettes and sterile tips
- Benchtop microcentrifuge
- -80 °C freezer for long-term storage; -20 °C freezer for short-term storage
- Ice bucket or cooling block to maintain sample integrity during handling
- Relevant assay reagents (substrates, cofactors such as NAD⁺/NADH, detection reagents) appropriate to the intended experimental application
Note: Always consult the Certificate of Analysis (CoA) supplied with your specific lot for confirmed formulation, concentration, and storage conditions, as these may vary between lots.
Reconstitution Procedure
Follow these steps to reconstitute Recombinant Human HSD17B11 Protein:
- Equilibrate the vial: Remove the vial from frozen storage and allow it to equilibrate briefly on ice (do not allow to reach room temperature before opening).
- Centrifuge: Briefly centrifuge the sealed vial (e.g., 5–10 seconds at low speed) to collect any lyophilized material from the sides and cap.
- Add reconstitution buffer: Slowly add the volume of sterile reconstitution buffer specified in the CoA along the inner wall of the vial. Do not add buffer directly onto the lyophilized cake to avoid denaturation.
- Gentle mixing: Gently swirl or pipette the solution carefully. Do not vortex, as vigorous agitation can denature the protein.
- Incubate: Allow the solution to stand on ice for 5–10 minutes to ensure complete dissolution.
- Inspect: Visually confirm the solution is clear and free of particulates. If turbidity is observed, centrifuge briefly at low speed before use.
- Aliquot: Divide the reconstituted protein into single-use aliquots in low-protein-binding tubes to avoid repeated freeze-thaw cycles.
Recommended working concentration: Determine empirically for each assay system. Refer to published literature on HSD17B11 enzyme assays for guidance on typical concentration ranges.
Storage and Stability
Proper storage is critical to maintaining the activity and integrity of Recombinant Human HSD17B11 Protein:
- Upon receipt: If the protein will be used within 1–2 weeks, store at -20 °C. For longer-term storage, store at -80 °C.
- Aliquots: After reconstitution, freeze single-use aliquots immediately at -80 °C to preserve enzymatic activity.
- Freeze-thaw cycles: Minimize freeze-thaw cycles. Each cycle may result in loss of protein activity. It is recommended to use each aliquot only once.
- Working solutions: Keep reconstituted protein on ice during experiments. Avoid prolonged exposure to room temperature.
- Shelf life: Refer to the expiry date printed on the product label and the CoA. Stability data specific to your lot will be provided in the CoA.
Disclaimer: Stability may vary depending on storage conditions and handling practices. Always follow the specific guidance provided in the CoA for your lot.
Experimental Applications and Assay Guidelines
Recombinant Human HSD17B11 Protein is suitable for a range of biochemical and cell-free research applications. HSD17B11 (17β-hydroxysteroid dehydrogenase type 11) is a member of the short-chain dehydrogenase/reductase (SDR) superfamily and is implicated in the metabolism of steroid hormones and lipid substrates.
Typical Applications
- Enzyme activity assays: HSD17B11 catalyzes the oxidation and reduction of steroids using NAD⁺/NADH cofactors. Activity can be measured spectrophotometrically by monitoring cofactor absorbance changes at 340 nm.
- Substrate specificity studies: Use the recombinant protein to characterize substrate preferences and kinetic parameters (Km, Vmax) under defined in vitro conditions.
- Inhibitor screening: Employ the protein in drug discovery workflows to identify and characterize small-molecule inhibitors of HSD17B11.
- Protein–protein interaction studies: Use as bait or prey protein in pull-down or co-immunoprecipitation experiments to identify interacting partners.
- Antibody validation: Use as a positive control antigen in Western blotting or ELISA to validate anti-HSD17B11 antibodies.
Note: Optimize assay conditions including buffer composition, pH, temperature, cofactor concentrations, and protein concentration empirically for each application.
Troubleshooting
Consult the table below if you encounter issues when working with Recombinant Human HSD17B11 Protein:
| Problem | Possible Cause | Suggested Action |
|---|---|---|
| No detectable enzyme activity | Protein denatured due to improper storage or handling; expired lot | Check storage temperature and freeze-thaw history; verify lot expiry; confirm cofactor (NAD⁺/NADH) is present and fresh |
| Low or variable activity | Repeated freeze-thaw cycles; suboptimal assay conditions | Use freshly thawed single-use aliquots; optimize buffer pH, temperature, and cofactor concentrations |
| Turbid or particulate solution after reconstitution | Protein aggregation; inappropriate buffer or temperature during reconstitution | Reconstitute on ice using recommended buffer; centrifuge briefly at low speed and use supernatant |
| Unexpected bands in Western blot | Non-specific binding; protein degradation | Optimize antibody concentration and blocking conditions; use freshly prepared protein; confirm protein integrity on a pre-run SDS-PAGE gel |
Frequently asked questions
What is HSD17B11 and why is it important in research?
HSD17B11 (17β-hydroxysteroid dehydrogenase type 11) is a member of the short-chain dehydrogenase/reductase (SDR) superfamily. It is involved in the metabolism of steroid hormones and lipid substrates, and has been implicated in conditions related to hormonal regulation and lipid metabolism. Recombinant HSD17B11 protein enables in vitro investigation of its enzymatic properties, substrate specificity, and potential as a therapeutic target.
How should I reconstitute and store Recombinant Human HSD17B11 Protein?
Reconstitute the lyophilized protein using the buffer type and volume specified in the Certificate of Analysis (CoA) for your lot. Add buffer gently along the vial wall and avoid vortexing. After reconstitution, aliquot into single-use volumes in low-protein-binding tubes and store at -80 °C for long-term use. Avoid repeated freeze-thaw cycles, as these can reduce enzymatic activity.
What cofactors are required for HSD17B11 enzyme activity assays?
HSD17B11, like other members of the SDR superfamily, requires nicotinamide adenine dinucleotide cofactors (NAD⁺ for oxidative reactions or NADH for reductive reactions) for catalytic activity. Ensure cofactors are prepared fresh and at appropriate concentrations for your assay. Optimize cofactor concentrations empirically for your specific experimental system.
Can Recombinant Human HSD17B11 Protein be used for inhibitor screening?
Yes, the recombinant protein is suitable for use in biochemical inhibitor screening assays. It can be incorporated into standard enzyme activity assay formats to identify small-molecule inhibitors of HSD17B11. Optimize protein concentration, substrate concentration, and assay conditions before conducting high-throughput or dose-response screening experiments.
What should I do if I observe no enzyme activity after reconstitution?
First, verify that the protein was stored correctly before use and has not undergone multiple freeze-thaw cycles. Confirm that fresh, appropriate cofactors (NAD⁺ or NADH) are present in the assay. Check the lot expiry date on the CoA. If the problem persists, contact Aladdin Scientific customer support with your lot number for further assistance.
References
- Marchais-Oberwinkler S, Henn C, Möller G, et al. 17β-Hydroxysteroid dehydrogenases (17β-HSDs) as therapeutic targets: protein structures, functions, and recent progress in inhibitor development. J Steroid Biochem Mol Biol. 2011;125(1-2):66-82. doi:10.1016/j.jsbmb.2010.12.013
- Filling C, Berndt KD, Benach J, et al. Critical residues for structure and catalysis in short-chain dehydrogenases/reductases. J Biol Chem. 2002;277(28):25677-25684. doi:10.1074/jbc.M202160200
- Aladdin Scientific. Recombinant Human HSD17B11 Protein (rp368124) Certificate of Analysis. Aladdin Scientific; [date specific to lot].
Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.
危险品化学品经营许可证（带存储）