Widespread Occurrence and Genomic Context of Unusually Small Polyketide Synthase Genes in Microbial Consortia Associated with Marine Sponges
2007
Fieseler, Lars | Hentschel, Ute | Grozdanov, Lubomir | Schirmer, Andreas | Wen, Gaiping | Platzer, Matthias | Hrvatin, Siniša | Butzke, Daniel | Zimmermann, Katrin | Piel, Jörn
Numerousmarine sponges harbor enormous amounts of as-yet-uncultivated bacteriain their tissues. There is increasing evidence that these symbiontsplay an important role in the synthesis of protective metabolites, manyof which are of great pharmacological interest. In this study, genesfor the biosynthesis of polyketides, one of the most important classesof bioactive natural products, were systematically investigated in 20demosponge species from different oceans. Unexpectedly, the spongemetagenomes were dominated by a ubiquitously present, evolutionarilydistinct, and highly sponge-specific group of polyketide synthases(PKSs). Open reading frames resembling animal fatty acid genes werefound on three corresponding DNA regions isolated from the metagenomesof Theonella swinhoei and Aplysina aerophoba. Theirarchitecture suggests that methyl-branched fatty acids are themetabolic product. According to a phylogenetic analysis of housekeepinggenes, at least one of the PKSs belongs to a bacterium of theDeinococcus-Thermus phylum. The results provide new insightsinto the chemistry of sponge symbionts and allow inference of adetailed phylogeny of the diverse functional PKS types present insponge metagenomes. Based on these qualitative and quantitative data,we propose a significantly simplified strategy for the targetedisolation of biomedically relevant PKS genes from complexsponge-symbiontassociations.
Mostrar más [+] Menos [-]Palabras clave de AGROVOC
Información bibliográfica
Este registro bibliográfico ha sido proporcionado por National Agricultural Library