Synonyms: Pepstatin A
Empirical Formula (Hill Notation): C34H63N5O9
Formula Weight: 685.89
Linear Formula: C34H63N5O9
MDL Number: MFCD00060740
Melting Point: 233 °C (dec.) (lit.)
Storage: 2-8°C
Beilstein Registry Number: 2201362
UNSPSC Code: 12352200
RIDADR: NONH for all modes of transport
Application:
Pepstatin is used for the protection of proteins and enzymes during isolation and purification procedures. It facilitates the investigation of enzyme mechanisms and biological function, and the classification of proteases. Pepstatin is applied in affinity chromatography, structural and pharmacological research, in HIV research (inhibition of retroviral-coded proteases, e.g., HIV-1), and cancer research (as an immunostimulant and anti-tumor drug).
Biochem/physiol Actions:
Pepstatin A is an inhibitor of acid proteases (aspartyl peptidases). It forms a 1:1 complex with proteases such as pepsin, renin, cathepsin D, bovine chymosin, and protease B (Aspergillus niger). The inhibitor is highly selective and does not inhibit thiol proteases, neutral proteases, or serine proteases. Solubilized γ-secretase and retroviral protease are also inhibited by Pepstatin A. It has been used to characterize proteases from several sources.
General description:
Isovaleryl-L-val-L-val-statyl-L-alanyl-statin (Isovaleryl-L-val-L-val-4-(S)-amino-3-(S)-hydroxy-6-methyl-heptanoyl-2-ala-4-(S)-amino-3-(S)-hydroxy-6-methyl-heptanoic acid)
Pepstatin is a low molecular weight, highly specific inhibitor of acid proteases (in particular aspartate proteases).
Other Notes:
For life science research only. Not for use in diagnostic procedures.
Quality:
Purity tested by HPLC.
Preparation Note:
Pepstatin can be dissolved at 1 mg/ml in 10% (v/v) acetic acid in methanol (9:1 methanol:acetic acid). The inclusion of acetic acid may be necessary to dissolve this peptide in methanol or DMSO. It has been dissolved at 1 to 2 mg/ml in ethanol, but heat may be required for complete dissolution. Solutions of Pepstatin A can be heated as high as 60 °C without any decomposition of the peptide.
Stock solutions at 1 mg/ml are stable at least a week at 4 °C. A 1 mM solution in methanol or DMSO is stable for months at -20 °C. If solutions become darker yellow, the reagent is hydrolyzing.
A working concentration of 1 μM is stable for at least one day at room temperature.
Reconstitution:
Soluble in methanol to approximately 1 mg/ml. Also soluble to 1 mg/ml in ethanol if allowed to sit overnight, and to 300 μg/ml in 6 N acetic acid. Stable for at least one week at 2 to 8 °C, or one month when stored in aliquots at -15 to -25 °C.
Specificity:
Pepstatin potently inhibits the HIV protease and other aspartic proteases, such as pepsin, renin, cathepsin D, chymosin, protease B from Aspergillus niger, and acid proteases of microbial origin.