• Aridibacter famidurans gen. nov., sp. nov. and Aridibacter kavangonensis sp. nov., two novel members of subdivision 4 of the Acidobacteria isolated from semiarid savannah soil.

      Huber, Katharina J; Wüst, Pia K; Rohde, Manfred; Overmann, Jörg; Foesel, Bärbel U; Helmholtz Centre for infection research, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2014-06)
      Acidobacteria constitute an abundant fraction of the soil microbial community and are currently divided into 26 subdivisions. Most cultivated members of the Acidobacteria are affiliated with subdivision 1, while only a few representatives of subdivisions 3, 4, 8, 10 and 23 have been isolated and described so far. Two novel isolates of subdivision 4 of the Acidobacteria were isolated from subtropical savannah soils and are characterized in the present work. Cells of strains A22_HD_4H(T) and Ac_23_E3(T) were immotile rods that divided by binary fission. Colonies were pink and white, respectively. The novel strains A22_HD_4H(T) and Ac_23_E3(T) were aerobic mesophiles with a broad range of tolerance towards pH (4.0-9.5 and 3.5-10.0, respectively) and temperature (15-44 and 12-47 °C, respectively). Both showed chemo-organoheterotrophic growth on some sugars, the amino sugar N-acetylgalactosamine, a few amino acids, organic acids and various complex protein substrates. Major fatty acids of A22_HD_4H(T) and Ac_23_E3(T) were iso-C(15 : 0), summed feature 1 (C(13 : 0) 3-OH/iso-C(15 : 1) H), summed feature 3 (C(16 : 1)ω7c/C(16 : 1)ω6c) and anteiso-C(17 : 0). The major quinone was MK-8; in addition, MK-7 occurred in small amounts. The DNA G+C contents of A22_HD_4H(T) and Ac_23_E3(T) were 53.2 and 52.6 mol%, respectively. The closest described relative was Blastocatella fastidiosa A2-16(T), with 16S rRNA gene sequence identity of 93.2 and 93.3%, respectively. Strains A22_HD_4H(T) and Ac_23_E3(T) displayed 16S rRNA gene sequence similarity of 97.4% to each other. On the basis of the low DNA-DNA hybridization value, the two isolates represent different species. Based on morphological, physiological and molecular characteristics, the new genus Aridibacter gen. nov. is proposed, with two novel species, the type species Aridibacter famidurans sp. nov. (type strain A22_HD_4H(T) = DSM 26555(T) = LMG 27985(T)) and a second species, Aridibacter kavangonensis sp. nov. (type strain Ac_23_E3(T) = DSM 26558(T) = LMG 27597(T)).
    • Labrenzia salina sp. nov., isolated from the rhizosphere of the halophyte Arthrocnemum macrostachyum.

      Camacho, Maria; Redondo-Gómez, Susana; Rodríguez-Llorente, Ignacio; Rohde, M; Spröer, Cathrin; Schumann, Peter; Klenk, Hans-Peter; Montero-Calasanz, Maria Del Carmen; Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2016-12)
      A novel, halophilic, motile, rod-shaped, Gram-staining-negative and non-endospore forming bacterium, designated Cs25T, was isolated from the rhizosphere of the halophyte Arthrocnemum macrostachyum growing in a tidal flat. Strain Cs25T was observed to be catalase-negative and oxidase-positive, and to hydrolyse hypoxanthine. Growth occurred from 15 to 40 °C, at pH 7.0-10.0 and with 1-11 % (w/v) NaCl. Q-10 was identified as the dominant ubiquinone, and the major cellular fatty acids were C18 : 1ω7c, 11-methyl C18 : 1ω7c, C20 : 1ω7c and C18 : 0. The polar lipids comprised phosphatidylmonomethylethanolamine, phosphatidylcholine, sulphoquinovosyldiacylglyceride, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The 16S rRNA gene showed 99.19, 98.6 and 98.59 % sequence identity with Labrenzia alba DSM 18320T, L. aggregata DSM 13394T and L. marina DSM 17023T, respectively. Based on the phenotypic and molecular features and DNA-DNA hybridization data, it is concluded that strain Cs25T represents a novel species for which the name Labrenzia salinasp. nov. is proposed. The type strain is Cs25T (=DSM 29163T=CECT 8816T).