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Palau'amine and related oroidin alkaloids dibromophakellin and dibromophakellstatin inhibit the human 20S proteasome.

ABSTRACT: We report herein that the oroidin-derived alkaloids palau'amine (1), dibromophakellin (2), and dibromophakellstatin (3) inhibit the proteolytic activity of the human 20S proteasome as well as the (i)20S immunoproteasome catalytic core. Palau'amine is found to prevent the degradation of ubiquitinylated proteins, including IκBα, in cell culture, which may be indicative of the potential mechanism by which these agents exhibit their exciting cytotoxic and immunosuppressive properties.

SUBMITTER: Lansdell TA

PROVIDER: S-EPMC3367325 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Palau'amine and related oroidin alkaloids dibromophakellin and dibromophakellstatin inhibit the human 20S proteasome.

Lansdell Theresa A TA Hewlett Nicole M NM Skoumbourdis Amanda P AP Fodor Matthew D MD Seiple Ian B IB Su Shun S Baran Phil S PS Feldman Ken S KS Tepe Jetze J JJ

Journal of natural products 20120516 5

We report herein that the oroidin-derived alkaloids palau'amine (1), dibromophakellin (2), and dibromophakellstatin (3) inhibit the proteolytic activity of the human 20S proteasome as well as the (i)20S immunoproteasome catalytic core. Palau'amine is found to prevent the degradation of ubiquitinylated proteins, including IκBα, in cell culture, which may be indicative of the potential mechanism by which these agents exhibit their exciting cytotoxic and immunosuppressive properties. ...[more]

PMID: 22591513

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