475815-M

Microcystin-LR, Microcystis aeruginosa

Cyclic heptapeptide toxin isolated from the freshwater cyanobacteria Microcystis aeruginosa.

• Synonym(s): Microcystin-LR, Microcystis aeruginosa, MCYST-LR
• Empirical Formula (Hill Notation): C₄₉H₇₄N₁₀O₁₂
• CAS Number: 101043-37-2
• Molecular Weight: 995.17
• MDL number: MFCD01774058
• UNSPSC Code: 12352200

Properties

• Quality Level: 100
• assay: ≥95% (HPLC)
• form: lyophilized solid
• manufacturer/tradename: Calbiochem^®
• storage condition: OK to freeze
• color: pale yellow
• solubility: methanol: 2 mg/mL; DMSO: 2.5 mg/mL
• storage temp.: −20°C
• InChI: 1S/C49H74N10O12/c1-26(2)23-37-46(66)58-40(48(69)70)30(6)42(62)55-35(17-14-22-52-49(50)51)45(65)54-34(19-18-27(3)24-28(4)38(71-10)25-33-15-12-11-13-16-33)29(5)41(61)56-36(47(67)68)20-21-39(60)59(9)32(8)44(64)53-31(7)43(63)57-37/h11-13,15-16,18-19,24,26,28-31,34-38,40H,8,14,17,20-23,25H2,1-7,9-10H3,(H,53,64)(H,54,65)(H,55,62)(H,56,61)(H,57,63)(H,58,66)(H,67,68)(H,69,70)(H4,50,51,52)/b19-18+,27-24+/t28-,29-,30-,31+,34-,35-,36+,37-,38-,40+/m0/s1
• InChI key: ZYZCGGRZINLQBL-GWRQVWKTSA-N

Description

General description

Cyclic heptapeptide toxin isolated from the freshwater cyanobacteria Microcystis aeruginosa. Potent inhibitor of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A). Unlike Okadaic Acid (Cat. No. 495604), microcystin-LR is effective on both PP1 (IC₅₀ = 1.7 nM) and PP2A (IC₅₀ = 40 pM). Reacts with phosphatase in a two-step mechanism involving rapid binding and inactivation of the catalytic subunit followed by slower covalent interactions. Has no effect on protein kinases, making it useful for reducing the effect of contaminating phosphatase activities in protein kinase assays. A 2.5 mM (250 µg/100 µl) solution of Microcystin-LR, Microcystis aeruginosa (Cat. No. 475821) in DMSO is also available.

Cyclic heptapeptide toxin isolated from the freshwater cyanobacteria, Microcystis aeruginosa. Potent inhibitor of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A). Unlike Okadaic Acid (Cat. No. 495604), microcystin-LR is effective on both PP1 (IC₅₀ = 1.7 nM) and PP2A (IC₅₀ = 40 pM). Has no effect on protein kinases, making it useful for reducing contaminating phosphatase activities in protein kinase assays.

Biochem/physiol Actions

Target IC₅₀: 1.7 nM and 40 pM against PP1 and PP2A, respectively

Warning

Toxicity: Highly Toxic (H)

Preparation Note

Further dilute with aqueous buffer just prior to use.

Reconstitution

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 6 months at -20°C. Unstable at > pH 7.7.

Other Notes

Craig, M., et al. 1996. Biochem. Cell Biol. 74, 569.
Nishiwaki, R., et al. 1994. Cancer Lett. 83, 283.
Amick, G.D., et al. 1992. Biochem. J.287, 1019.
Davidson, H.W., et al. 1992. J. Cell Biol.116, 1343.
Nishiwaki-Matsushima, R., et al. 1992. J. Cancer Res. Clin. Oncol. 118, 420.
Cohen, P., et al. 1990. Trends Biochem. Sci.15, 98.
MacKintosh, C., et al. 1990. FEBS Lett.264, 187.
Cohen, P., et al. 1989. FEBS Lett.250, 596.
Carmichael, W.W. 1988. in Handbook of Natural Toxins3: Marine Toxins and Venoms(Tu, A.T., Ed.) p. 121, Decker, New York.

Legal Information

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

Safety Information

• pictograms: GHS06
• signalword: Danger
• hcodes: H300 + H310,H315,H317,H319,H335
• pcodes: P261 - P262 - P280 - P301 + P310 - P302 + P352 + P310 - P305 + P351 + P338
• Hazard Classifications: Acute Tox. 2 Dermal - Acute Tox. 2 Oral - Eye Irrit. 2 - Skin Irrit. 2 - Skin Sens. 1 - STOT SE 3
• target_organs: Respiratory system
• Storage Class: 6.1A - Combustible acute toxic Cat. 1 and 2 / very toxic hazardous materials
• wgk_germany: WGK 3
• flash_point_f: Not applicable
• flash_point_c: Not applicable