The marine lithistid sponge Theonella swinhoei from Palau contains the
cytotoxic macrolide swinholide and the antifungal bicyclic
glycopeptide theopalauamide. Symbiotic bacteria associated with the
interior tissue of the sponge are the suspected producers of the
natural products, and not the sponge itself. In collaboration with
Prof. John Faulkner (Scripps Institution of Oceanography), we traveled
to Palau in the summer of 1998 and collected the sponge by SCUBA. We
have shown through molecular phylogenetic studies that the sponge
hosts a very complex assemblage of microorganisms. We are now studying
the involvement of the microflora in the biosynthesis of these
metabolites. As the associated bacteria are largely uncultivatable, we
plan to clone and heterologously express these very large gene sets in
surrogate bacterial hosts.
