Palau’amine and Related Oroidin Alkaloids Dibromophakellin and Dibromophakellstatin Inhibit the Human 20S Proteasome
journal contributionposted on 25.05.2012, 00:00 by Theresa A. Lansdell, Nicole M. Hewlett, Amanda P. Skoumbourdis, Matthew D. Fodor, Ian B. Seiple, Shun Su, Phil. S. Baran, Ken S. Feldman, Jetze J. Tepe
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 i20S 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.