Physical Appearance:  Colorless oil

Molecular Formula:  C₄₄H₆₈O₁₃

Molecular Weight:  805.0

Purity:  98% (HPLC)

Solubility:  Soluble in ethanol (25 mg/ml) and DMSO (25 mg/ml)

Storage:  Freezer (-20℃). Protect from light. Following reconstitution, aliquot and freeze (-20℃). This product is stable for 2 years as supplied. Stock solutions are stable for up to 1 month at -20℃.

Description:  An ionophore-like polyether derivative of a C38 fatty acid compound isolated from the dinoflagellate Prorocentrum sp. that has fed on the marine sponge Halinchrondria okadai. It is a potent non-comepetitive, reversible inhibitor of serine/threonine-specific protein phosphatases 1 (PP1, IC₅₀ = 10-15 nM, rabbit skeletal muscle, catalytic subunit) and 2A (PP2A, IC₅₀ = 0.1 nM, rabbit skeletal muscle, catalytic subunit). It has only a trivial effect on protein phosphatase 2B (IC₅₀ = 5 μM), a Ca²⁺/calmodulin-dependent enzyme, while PP2C, a Mg²⁺ dependent enzyme, is unaffected. Okadaic acid has no significant effect on the activities of tyrosine phosphatases, alkaline phosphatase, acid phosphatase, and inositol trisphosphatase. It is also a non-phorbol ester-type tumor promoter on mouse skin. Useful for the study of protein phosphatases and of PP1/PP2A in cell extracts, as well as in intact cells. Induces apoptosis in human breast carcinoma (MB-231 and MCF-7) and in myeloid cells, but inhibits glucocorticoid-induced apoptosis in T-cell hybridomas. Has marked contractile effect on smooth muscles and heart muscles. Implicated as a causative agent of diarrhetic shellfish poisoning.

References:

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3.      R.E. Honkanen et al. J. Biol. Chem. 1990 265 19401

4.      C. Biolojan et al. Biochem. J. 1988 256 283

5.      B. Favre et al. J. Biol. Chem. 1997 272 13856

6.      D.G. Hardie et al. Methods Enzymol. 1991 201 469

CAUTION!!! Avoid all forms of contact with this product by wearing appropriate protective clothing (gloves, mask, lab coat). The Material Safety Data Sheet (MSDS), is available on request.