Desmospora activa gen. nov., sp. nov., a thermoactinomycete isolated from sputum of a patient with suspected pulmonary tuberculosis, and emended description of the family Thermoactinomycetaceae Matsuo et al. 2006

1 Institut für Medizinische Mikrobiologie und Immunologie der Universität Bonn, Sigmund-Freud-Straße 25, 53127 Bonn, Germany 2 Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, 53121 Bonn, Germany 3 DSMZ – German Collection of Microorganisms and Cell Cultures, Inhoffenstraße 7B, 38124 Braunschweig, Germany Correspondence A. F. Yassin yassin{at}mibi03.meb.uni-bonn.de A novel Gram-positive, aerobic, catalase-positive, filamentous micro-organism, designated strain IMMIB L-1269 T , originating from sputum was characterized using phenotypic and molecular taxonomic methods. It showed cell-wall chemotype III, phospholipid type PII (with phosphatidylethanolamine as the diagnostic phospholipid) and contained an unsaturated menaquinone with seven isoprene units (MK-7) as the predominant isoprenoid quinone. It synthesized long-chain cellular fatty acids of the straight-chain saturated, monounsaturated and iso- and anteiso-branched types (with iso-C 15 : 0 , C 16 : 0 and iso-C 17 : 0 predominating) and possessed a DNA G+C content of 49.3 mol%. On the basis of its morphological, biochemical and chemical characteristics, strain IMMIB L-1269 T did not conform to any presently recognized taxon. Comparative analyses based on 16S rRNA gene sequences confirmed the distinctiveness of the isolate, as it displayed sequence-divergence values greater than 7.7 % with respect to recognized Gram-positive taxa. Phylogenetic treeing analysis served to reinforce the view that strain IMMIB L-1269 T was distinct from recognized taxa, as it formed a relatively long subline branching within a 16S rRNA gene sequence cluster that encompassed the genera Thermoactinomyces , Laceyella , Mechercharimyces , Thermoflavimicrobium , Planifilum , Seinonella and Shimazuella of the family Thermoactinomycetaceae . On the basis of phenotypic and molecular phylogenetic evidence, strain IMMIB L-1269 T represents a novel genus and species, for which the name Desmospora activa gen. nov., sp. nov. is proposed. The type strain of Desmospora activa is strain IMMIB L-1269 T (=DSM 45169 T =CCUG 55916 T ). An emended description of the family Thermoactinomycetaceae is also given. The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain IMMIB L-1269 T is AM940019 . Micrographs of strain IMMIB L-1269 T , showing aerial mycelium, endospores and chains of arthrospores, and a two-dimensional TLC of the polar lipids are available as supplementary material with the online ve