Paucibacter toxinivorans gen. nov., sp. nov., a bacterium that degrades cyclic cyanobacterial hepatotoxins microcystins and nodularin

1 Finnish Environment Institute, PO Box 140, FIN-00251 Helsinki, Finland 2 Fachgebiet Ökologie der Mikroorganismen, Institut für Technischen Umweltschutz, Technische Universität Berlin, D-10587 Berlin, Germany 3 Institute of Biotechnology, PO Box 56, FIN-00014 University of Helsinki, Finland Correspondence Jarkko Rapala jarkko.rapala{at}sttv.fi Thirteen bacterial isolates from lake sediment, capable of degrading cyanobacterial hepatotoxins microcystins and nodularin, were characterized by phenotypic, genetic and genomic approaches. Cells of these isolates were Gram-negative, motile by means of a single polar flagellum, oxidase-positive, weakly catalase-positive and rod-shaped. According to phenotypic characteristics (carbon utilization, fatty acid and enzyme activity profiles), the G+C content of the genomic DNA (66·1–68·0 mol%) and 16S rRNA gene sequence analysis (98·9–100 % similarity) the strains formed a single microdiverse genospecies that was most closely related to Roseateles depolymerans (95·7–96·3 % 16S rRNA gene sequence similarity). The isolates assimilated only a few carbon sources. Of the 96 carbon sources tested, Tween 40 was the only one used by all strains. The strains were able to mineralize phosphorus from organic compounds, and they had strong leucine arylamidase and chymotrypsin activities. The cellular fatty acids identified from all strains were C 16 : 0 (9·8–19 %) and C 17 : 1 7 c (