Investigation of polyketide biosynthetic pathways in the sponge Theonella swinhoei and the beetle Paederus fuscipes [Elektronische Ressource] / vorgelegt von Tu Anh Nguyen

Investigation of polyketide biosynthetic pathways in the sponge Theonella swinhoei and the beetle Paederus fuscipes Dissertation zur Erlangung des Doktorgrades (Dr. rer. nat.) der Mathematisch-Naturwissenschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn vorgelegt von Tu Anh Nguyen aus Ha Noi, Viet Nam Bonn (2009) Angefertigt mit Genehmigung der Mathematisch-Naturwissenschaftlichen Fakultät der Rheinischen Friedrich-Wilhelms-Universität Bonn. Gutachter: 1. Prof. Dr. Jörn Piel 2. Prof. Dr. Gabriele M. König 3. Prof. Dr. Christa E. Müller 4. Prof. Dr. Hans-Georg Sahl Tag der Promotion: 7. 12. 2009 Abstract Onnamides are natural products that possess strong antitumor activity and were isolated from the marine sponge Theonella swinhoei. Previous data suggested that an as-yet unculturable symbiotic bacterium living in association with the sponge is the actual onnamide producer. In order to gain insight into the biosynthetic pathway of onnamides in nature, their biosynthetic genes had to be identified. Onnamides are encoded by the onnamide (onn) gene cluster, which contains giant trans-AT polyketide synthase (PKS) and nonribosomal peptide synthase (NRPS) genes. PKSs and NRPSs are constituted of modules, each module consisting of domains.