PR-39

PR-39, a natural proline- and arginine-rich antibacterial peptide, is a noncompetitive, reversible and allosteric proteasome inhibitor. PR-39 reversibly binds to the α7 subunit of the proteasome and blocks degradation of NF-κB inhibitor IκBα by the ubiquitin-proteasome pathway. PR-39 stimulates angiogenesis, inhibits inflammatory responses and significant reduces myocardial infarct size in mice[1][2].

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[1]Maria Gaczynska, et al. Proline- and arginine-rich peptides constitute a novel class of allosteric inhibitors of proteasome activity. Biochemistry. 2003 Jul 29;42(29):8663-70.|[2]Y Gao, et al. Inhibition of ubiquitin-proteasome pathway-mediated I kappa B alpha degradation by a naturally occurring antibacterial peptide. J Clin Invest. 2000 Aug;106(3):439-48.