EN
Human Cathepsin B
Native whole molecule & biologically active
Product Overview, Sizes and Prices | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Proteins Synonyms: CatB, APP secretase, APPS, CTSB Biological Activity: ≥ 200 units/mg protein Source: Human Liver Purity: ≥ 95% by SDS-PAGE Physical State: Frozen in 50 mM Na Acetate, pH 5.0, with 1 mM EDTA Manufacturer: |
|
|||||||||||||||||
Athens Research & Technology
Produktdetails
Synonyms
CatB, APP secretase, APPS, CTSB
Description of Human Cathepsin B
Cathepsin B is a lysosomal cysteine protease synthesized as a 339-amino acid preproenzyme that matures into a heterodimer of 27.5 kDa and 5 kDa subunits linked by disulfide bonds. Its unique occluding loop structure enables dual endopeptidase and exopeptidase activities, preferentially cleaving substrates with hydrophobic or basic residues at pH 4.6 (lysosomal) versus neutral pH 7.2 (cytosolic). Beyond intracellular protein degradation, Cathepsin B modulates lysosomal biogenesis by regulating transcription factor EB (TFEB) and mechanistic target of rapamycin (mTOR) pathways, enhancing autophagy for pathogen clearance. In thyroid epithelial cells, it processes thyroglobulin to liberate thyroxine, requiring TSH-dependent secretion of mature enzyme from lysosomes. Pathologically, Cathepsin B overexpression drives cancer metastasis by degrading extracellular matrix components at tumor invasive fronts, correlating with poor prognosis in breast, lung, and cervical cancers. In Alzheimer’s disease, lysosomal leakage releases Cathepsin B into the cytosol, where it cleaves tau and amyloid precursor protein, exacerbating neurofibrillary tangles and neuronal death. Traumatic brain injury models show Cathepsin B knockout reduces Bax-mediated apoptosis and motor deficits. Rheumatoid arthritis synovial fibroblasts exhibit CTSB-dependent ferroptosis, with inhibition by CA-074Me suppressing lipid ROS accumulation and migration. Therapeutically, pH-selective inhibitors like Z-Arg-Lys-AOMK (IC₅₀ = 20 nM at pH 7.2) target cytosolic Cathepsin B in neurodegeneration while sparing lysosomal function. In breast cancer, dual inhibition of Cathepsin B and Z reduces lung metastasis by 70%, highlighting synergy in protease targeting. Diagnostic applications leverage elevated serum Cathepsin B as a biomarker for sepsis severity (>45 ng/mL), COVID-19 progression, and cardiovascular risk stratification. These multifaceted roles underscore its potential as a therapeutic node across oncology, neurology, and autoimmunity.
Source
Prepared from liver shown to be non reactive for HBsAg, anti-HCV, anti-HBc, and negative for anti-HIV 1 & 2 by FDA-required tests.
Biological Activity
≥ 200 units/mg protein. One unit is defined as the amount of enzyme that hydrolyzes 1 µmol of Z-Arg-Arg-beta-naphthylamide per minute at 40 °C, using 100 mM Na/K phosphate, pH 6.0, with 1.33 mM EDTA and 2 mM DTT as the activation buffer
Storage
For long term, store Human Cathepsin B at ≤ -80°C.
Applications
Cancer, Alzheimer's, Brain Injury, Rheumatoid Arthritis, In Vitro Diagnostics.
Citations/Publications
Luo, D. et al., (2020), 'Nanoparticles Yield Increased Drug Uptake and Therapeutic Efficacy upon Sequential Near-Infrared Irradiation', ACS Nano, 14: pp 15193−15203. Available at: https://dx.doi.org/10.1021/acsnano.0c05425
Luo, D., et al., (2022), 'Targeted Chemoradiotherapy of Prostate Cancer Using Gold Nanoclusters with Protease Activatable Monomethyl Auristatin E', ACS Appl. Mater. Interfaces, 14: pp 14916−14927. Available at: https://doi.org/10.1021/acsami.1c23780
Kratschmer, C., et al., (2018), 'Targeted Delivery of Auristatin-Modified Toxins to Pancreatic Cancer Using Aptamers', Molecular Therapy: Nucleic Acids., 10: pp 227-236. Available at: https://doi.org/10.1016/j.omtn.2017.11.013
Sanman, L. E., et al., (2016), 'Bifunctional Probes of Cathepsin Protease Activity and pH Reveal Alterations in Endolysosomal pH during Bacterial Infection', Cell Chemical Biology, 23(7): pp 793 - 804. Available at: http://dx.doi.org/10.1016/j.chembiol.2016.05.019
Gbadegesin, O. D., et al., (2025), 'Gemcitabine–Doxorubicin Combination Polymer-Drug Conjugate Prepared by SPAAC Click Chemistry: In Vitro Characterization', Int. J. Mol. Sci., 26: pp 2798. Available at: https://doi.org/10.3390/ijms26062798
NCBI: https://www.ncbi.nlm.nih.gov/protein/P07858/
Shipped with dry ice
Gel Scan of Human Cathepsin B
| Fig. 1: SDS-PAGE Gel |
Usage: For research use only. Not for use in diagnostic or therapeutic procedures. Not for human use.
To buy Human Cathepsin B please click on the Shopping List Symbol right from the indicated price. This will add Human Cathepsin B to your Shopping List. You can then click on the button »Shopping List & Order Form« to ask for a quote. We will send you your quote as soon as possible. Our offer will include institutional discounts where applicable.
For business customers only. All prices are net prices (excluding VAT). Final prices in our quote will contain VAT plus shipping costs if applicable. For further information please go to our Shipping page.
Errors, changes and availability excepted.
Payment Methods
Paying by bank transfer
