Goecke, F. R., Thiel, V. ., Wiese, J. ., Labes, A. ., & Imhoff, J. F. (2013). Algae as important environment for bacteria - phylogenetic relationships among species isolated from algae. Phycologia, 52, 14–24. Abgerufen von http://oceanrep.geomar.de/19593/
Abstract
Bacteria are an inherent part of the biotic environment of algae. Recent investigations revealed that bacterial communities associated with algae were generally highly host specific. Several new bacterial species and genera were isolated from algae, which suggested that algae were an interesting environment for discovery of new bacterial taxa; however, the distribution of the different phylogenetic groups among those isolates remained unclear, and this information could help to explain specific associations. We conducted a phylogenetic study based on 16S rRNA gene sequences available in GenBank, including 101 validly described bacterial species that were isolated from eukaryotic macro- and micro-algae from marine and freshwater environments. These species were distributed among six bacterial phyla, including: Bacteroidetes (42 species), Proteobacteria (36 species), and Firmicutes, Actinobacteria, Verrucomicrobia and Planctomycetes (23 species). Bacterial species and strains that carried out similar metabolic functions were found to colonize similar algal taxa or algal groups. This assumption was supported by information available from bacterial species descriptions: (1) Most of the bacteria described from microalgae grouped into the Roseobacter clade (Alphaproteobacteria), which indicated that members of this group were well adapted for life in close association with phytoplankton; and (2) 32\% of the bacterial species, mainly isolates from macroalgae, were able to decompose macroalgal polysaccharides. Because algal-bacterial association are still under-studied in various algal groups, we expect a great number of new bacterial taxa to be discovered in the future.
Labes, A. . (2013). Genome based methods for the exploration of natural products from marine fungi for the treatment of cancer. In Tagung der Vereinigung für allgemeine und angewandte Mikrobiologie. Abgerufen von http://oceanrep.geomar.de/23000/
Oesterwalbesloh, J. ., Wiese, J. ., Labes, A. ., & Imhoff, J. F. (2013). Habitat specific provocation of secondary metabolite production by marine bacteria ? microbial communication and pharmaceutical use. In VAAM Jahrestagung 2013. Abgerufen von http://oceanrep.geomar.de/20913/
Penzenstadler, B. ., Khurum, M. ., & Petersen, K. . (2013). Towards Incorporating Sustainability while Taking Software Product Management Decisions. In 7th International Workshop on Software Product Management (S. 71–58).
Labes, A. . (2013). Bio-mining the microbial treasures of the ocean: Early drug discovery and models for entering pharmaceutical pipelines. In SUBMARINER. Abgerufen von http://oceanrep.geomar.de/23002/
Baca, D. ., Carlsson, B. ., Petersen, K. ., & Lundberg, L. . (2013). Improving software security with static automated code analysis in an industry setting. Software: Practice and Experience, 43, 259–279.
Paun, L. ., Kramer, A. ., Hihlal, E. ., Labes, A. ., Imhoff, J. F., & Kempken, F. . (2013). Higher yields of cyclodepsipetides from Scopulariopsis brevicaulis by random mutagenesis. In 27. Fungal Genetics Conference. Abgerufen von http://oceanrep.geomar.de/22016/
Abstract
The ascomycete Scopulariopsis brevicaulis, which was isolated from the marine sponge Tethya aurantium, produces two cyclodepsipeptides, scopularides A and B [1]. Both peptides exhibit activity against several tumor cell lines. Within the EU-project MARINE FUNGI (EU FP7, 265926) one of our aims is to enhance the production of these secondary metabolites. We are in the process to establish two ways of random mutagenesis by both UV radiation and transposon-mediated. To this end we created UV-mutants and a miniaturised screening method was developed. UV-radiation was performed at 312 nm and the survival rate was set to 1 \%. With this method a mutant library was established. To screen these mutants for higher secondary metabolites production, we developed a miniaturised screening method which includes decreased cultivation volume, fast extraction and an optimised LC-MS analysis format. Using the UV mutagenesis, we were able to identify several mutants with a higher scopularide production in comparison to the wild type. One of these mutants, which produces three times more biomass and more than double the amount of scopularide A, has been used for another round of mutation. Next generation sequencing is being employed to identify the molecular genetic basis of the observed mutations. In parallel we employ transposable elements to introduce mutants [2]. The impact of transposons on gene expression as well as their ability to cause major mutations within the genome or single genes makes them an interesting tool for random mutagenesis [3, 4, 5]. We employ the Vader transposon in its homologous host and found that Vader mostly integrates within or very close to genes. Thus it appears to be a useful tool for transposon-mediated mutagenesis in A. niger (6). At current we try to enhance its usability by modifying the Vader element.