Cytoprotektive Arzneistoffe aus niederen marinen Organismen. Teilprojekt: Naturstoffgewinnung aus endosymbiontischen marinen Mikroorganismen Schlussbericht

From 15 marine sponges harvested at the Adriatic coast and in the Aegean Sea, respectively, we have isolated approximately 150 different bacteria. After cultivation and screening for novel natural compounds we have focussed on three bacteria, which showed interesting results in antimicrobial assays. The bacteria were identified by 16S rDNA technology and the molecular structures of the products were elucidated: Pseudoalteromonas piscicida from Crella rosea was able to synthesize hexadecenoic acid and heptadecenoic acid, resp., which were active against Staphylococcus aureus and Pseudomonas aeruginosa. Besides amino acid degradation compounds, Microbacterium spec. from Halichondria panicea produced a novel glycoglyerolipid. In the case of Staphylococcus hominis from Halichondria cratera unsaturated fatty acids were detected as antimicrobially acting substances. As for all three bacteria, intensive studies on the optimization of growth and natural compound production were carried out in 10 l - 50 l bioreactors. Up to 200 mg l"-"1 of pure active substances have been producted. To dominat glycoglycerolipid GGL.2 and its corresponding hydrolysis product (from alkaline treatment) showed good antitumoral properties; they inhibited the TPA induced activation of the Epstein-Barr-virus early antigen (EBV-EA). These compounds as well as the previously mentioned natural products were able to inhibit protein kinases too, but in a nonspecific manner. Some of the microbial crude products showed NMDA antagonistic effects in the ["3H]-MK 801 binding assay, other raw materials indicated cytotoxic effects on the tumoral cell line L5178Y. In the future it is necessary to use chromatographically enriched products for these studies. (orig.)SIGLEAvailable from TIB Hannover: F99B1246+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman