Mar.Drugs 2003,1 2 to belong to the 8-proteobacteria as a sister taxon to Myxococcales.The respective bacteria have been assigned the taxonomic status"Candidatus Entotheonella palauensis"[22].T.swinhoei is by no means a singular case since bacteria were also shown to be producers of natural products in the sponge Dysidea herbacea.Using a cell sorter it was demonstrated that the amino acid derivative 13-demethylisodysidenin (Fig.5)was the major natural product identified in the fluorescent cell fraction(cyanobacteria)whereas sponge cells and bacteria (the latter were not separated in this case)contained spirodysin and herbadysidolide [23,24]. Figure 4.Microbial secondary metabolites and closely related analogues also found in marine invertebrates rom Symploca hydnoides (cyanobacterium nd Eudistoma(tunicate) okadaic aci and Halichondria spp.(sponges)Mar. Drugs 2003, 1 12 to belong to the δ-proteobacteria as a sister taxon to Myxococcales. The respective bacteria have been assigned the taxonomic status “Candidatus Entotheonella palauensis” [22]. T. swinhoei is by no means a singular case since bacteria were also shown to be producers of natural products in the sponge Dysidea herbacea. Using a cell sorter it was demonstrated that the amino acid derivative 13-demethylisodysidenin (Fig. 5) was the major natural product identified in the fluorescent cell fraction (cyanobacteria) whereas sponge cells and bacteria (the latter were not separated in this case) contained spirodysin and herbadysidolide [23, 24]. Figure 4. Microbial secondary metabolites and closely related analogues also found in marine invertebrates N O H N CH3 H3C CH3 H3C CH3 O N CH3 CH3 OCH3 O N H3CO CH3 O N H S N dolastatin 10 (R = H) symplostatin 1 (R = CH3) from Symploca hydnoides (cyanobacterium) and Dolabella auricularia (mollusc) CH3 N N H N O NHCH3 O H3C H3CO O O O O O O O CH3 H3C OH HOOC OH CH3 OH CH2 OH H3C CH3 H H H H H H H staurosporine from Saccharothrix aerocolonigenes subsp. staurosporea (actinomycete) and Eudistoma toealensis (tunicate) okadaic acid from Prorocentrum spp. (dinoflagellates) and Halichondria spp. (sponges) R