• Nature

  • Source

    Escherichia coli
  • Amino Acid Sequence
    • Accession
    • Species



Our Abpromise guarantee covers the use of ab52203 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

  • Biological activity

    SPECIFIC ACTIVITY: 400 units/mg
  • Applications


  • Purity

    > 90 % SDS-PAGE.

  • Form

  • Additional notes

    UNIT DEFINITION: One unit of the recombinant Caspase 9 is the enzyme activity that cleaves 1 nmol of the caspase substrate LEHD-pNA (pNA: pnitroanaline) per hour at 37°C in a reaction solution containing 50 mM Hepes, pH 7.2, 50 mM NaCl, 0.1% Chaps, 10 mM EDTA, 5% Glycerol, and 10 mM DTT.
  • Concentration information loading...

Preparation and Storage

  • Stability and Storage

    Shipped at 4°C. Upon delivery aliquot. Store at -80°C. Avoid freeze / thaw cycle.

    Constituents: PBS, 15% Glycerol

    This product is an active protein and may elicit a biological response in vivo, handle with caution.

  • Reconstitution
    Reconstitute to 1 unit per µl in PBS containing 15% glycerol. Following reconstitution in PBS, the enzyme should be aliquoted and immediately stored at –70°C.

General Info

  • Alternative names

    • APAF-3
    • APAF3
    • Apoptosis related cysteine peptidase
    • Apoptotic protease Mch-6
    • Apoptotic protease-activating factor 3
    • CASP-9
    • CASP9
    • Caspase 9 apoptosis related cysteine peptidase
    • Caspase 9 Dominant Negative
    • Caspase 9c
    • Caspase-9
    • Caspase-9 subunit p10
    • ICE LAP6
    • ICE like apoptotic protease 6
    • ICE-LAP6
    • ICE-like apoptotic protease 6
    • MCH6
    • PPP1R56
    • protein phosphatase 1, regulatory subunit 56
    • RNCASP9
    see all
  • Function

    Involved in the activation cascade of caspases responsible for apoptosis execution. Binding of caspase-9 to Apaf-1 leads to activation of the protease which then cleaves and activates caspase-3. Proteolytically cleaves poly(ADP-ribose) polymerase (PARP).
    Isoform 2 lacks activity is an dominant-negative inhibitor of caspase-9.
  • Tissue specificity

    Ubiquitous, with highest expression in the heart, moderate expression in liver, skeletal muscle, and pancreas. Low levels in all other tissues. Within the heart, specifically expressed in myocytes.
  • Sequence similarities

    Belongs to the peptidase C14A family.
    Contains 1 CARD domain.
  • Developmental stage

    Expressed at low levels in fetal heart, at moderate levels in neonate heart, and at high levels in adult heart.
  • Post-translational

    Cleavages at Asp-315 by granzyme B and at Asp-330 by caspase-3 generate the two active subunits. Caspase-8 and -10 can also be involved in these processing events.
  • Information by UniProt


  • Lane 1: Recombinant caspase 9 protein (Active) ab52203- 100 ng. Lane 2: BSA- 400 ng. Lane 3: BSA- 200 ng. Lane 4: BSA- 100 ng. Lane 5: BSA- 50 ng. Lane 6: BSA- 25 ng. SYPRO Ruby protein stain. Predicted band size: 46 kDa (precursor protein) and 35 kDa (p35 subunit) Observed Bands: 20 kDa and 11 kDa.


This product has been referenced in:

  • Basu A  et al. Proteolytic activation of protein kinase C-epsilon by caspase-mediated processing and transduction of antiapoptotic signals. J Biol Chem 277:41850-6 (2002). Read more (PubMed: 12198125) »
  • Azuma T  et al. Gelsolin in complex with phosphatidylinositol 4,5-bisphosphate inhibits caspase-3 and -9 to retard apoptotic progression. J Biol Chem 275:3761-6 (2000). Read more (PubMed: 10660524) »
See all 2 Publications for this product

Customer reviews and Q&As

1-2 of 2 Abreviews or Q&A


Thank you for contacting Abcam.

I have spoken to tha lab regarding ab52203 and please find their response below:

This protein is N-terminal His Tagged.
The mol wt of this product is ˜30 kDa.
The amount of protein in terms of µg might vary slightly from lot to lot; therefore it comes in terms of units, which are constant between lots. One unit of the recombinant caspase-9 is the enzyme activity that cleaves 1 nmol of the caspase substrate LEHD-pNA (pNA: pnitroanaline) per hour at 37°C in a reaction solution containing 50 mM Hepes, pH 7.2, 50 mM NaCl, 0.1% Chaps, 10 mM EDTA, 5% Glycerol, and 10 mM DTT.
Hope this information has been helpful for you.

Please let me know if you have any other questions.

Read More


Thank you for contacting Abcam.

From the attached data it appears that the antibody 1 and 2 recognize the band which is ˜44 kDa. In addition to the 45 kDa procaspase-9 and 35/37 kDa cleaved large fragment there is also a 25 kDa fully cleaved caspase-9 and the customer most likely is detecting this form.

Please let me know if you have any more questions.

Read More

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