• Asticcacaulis benevestitus sp. nov., a psychrotolerant, dimorphic, prosthecate bacterium from tundra wetland soil.

      Vasilyeva, Lina V; Omelchenko, Marina V; Berestovskaya, Yulia Y; Lysenko, Anatolii M; Abraham, Wolf-Rainer; Dedysh, Svetlana N; Zavarzin, George A; S. N. Winogradsky Institute of Microbiology, Russian Academy of Sciences, Prospect 60-let Octyabrya 7/2, Moscow 117312, Russia. (2006-09)
      A Gram-negative, aerobic, heterotrophic, non-pigmented, dimorphic prosthecate bacterium was isolated from tundra wetland soil and designated strain Z-0023(T). Cells of this strain had a dimorphic life cycle and developed a non-adhesive stalk at a site not coincident with the centre of the cell pole, a characteristic typical of representatives of the genus Asticcacaulis. A highly distinctive feature of cells of strain Z-0023(T) was the presence of a conical, bell-shaped sheath when grown at low temperature. This prosthecate bacterium was a psychrotolerant, moderately acidophilic organism capable of growth between 4 and 28 degrees Celsius (optimum 15-20 degrees Celsius) and between pH 4.5 and 8.0 (optimum 5.6-6.0). The major phospholipid fatty acid was 18 : 1omega7c and the major phospholipids were phosphatidylglycerols. The G+C content of the DNA was 60.4 mol%. On the basis of 16S rRNA gene sequence similarity, strain Z-0023(T) was most closely related to Asticcacaulis biprosthecium (98 % similarity), Asticcacaulis taihuensis (98 %) and Asticcacaulis excentricus (95 %). However, low levels of DNA-DNA relatedness to these organisms and a number of distinctive features of the tundra wetland isolate indicated that it represented a novel species of the genus Asticcacaulis, for which the name Asticcacaulis benevestitus sp. nov. is proposed. The type strain is Z-0023(T) (=DSM 16100(T)=ATCC BAA-896(T)).
    • Brevundimonas vancanneytii sp. nov., isolated from blood of a patient with endocarditis.

      Estrela, Andréia B; Abraham, Wolf-Rainer; Helmholtz Center for Infection Research, Chemical Microbiology, Inhoffenstrasse 7, 38124 Braunschweig, Germany. (2010-09)
      A Gram-negative, rod-shaped, non-spore-forming bacterial strain, designated LMG 2337(T), was isolated from the blood of a patient with endocarditis and characterized. The strain was affiliated with the alphaproteobacterial genus Brevundimonas, with Brevundimonas diminuta LMG 2089(T) (98.3 % 16S rRNA gene sequence similarity) and Brevundimonas terrae KSL-145(T) (97.5 %) as its closest relatives. This affiliation was supported by chemotaxonomic data: the G+C content was 66.3 mol %, the major polar lipids were phosphatidyl diacylglycerol, sulfoquinovosyl diacylglycerol and phosphatidyl glucopyranosyl diacylglycerol and the major fatty acids were summed feature 7 (one or more of C(18 : 1)ω 7c, C(18 : 1)ω 9t and C(18 : 1)ω 12t) and C(16 : 0). Strain LMG 2337(T) displayed an unusually broad substrate spectrum. The results from DNA-DNA hybridization and physiological and biochemical tests allowed the genotypic and phenotypic differentiation of strain LMG 2337(T) from all of the type strains of hitherto-described Brevundimonas species. The strain therefore represents a novel species, for which the name Brevundimonas vancanneytii sp. nov. is proposed, with type strain LMG 2337(T) (=CCUG 1797(T) =ATCC 14736(T)).
    • Sphingobium aromaticiconvertens sp. nov., a xenobiotic-compound-degrading bacterium from polluted river sediment.

      Wittich, Rolf-Michael; Busse, Hans-Jürgen; Kämpfer, Peter; Tiirola, Marja; Wieser, Monika; Macedo, Alexandre J; Abraham, Wolf-Rainer; Helmholtz Zentrum für Infektionsforschung (formerly GBF), Division Microbiology, D-38124 Braunschweig, Germany. (2007-02)
      A bacterial strain capable of degrading some monochlorinated dibenzofurans, designated RW16T, was isolated from aerobic River Elbe sediments. The strain was characterized based on 16S rRNA gene sequence analysis, DNA G+C content, physiological characteristics, polyamines, ubiquinone and polar lipid pattern and fatty acid composition. This analysis revealed that strain RW16T represents a novel species of the genus Sphingobium. The DNA G+C content of strain RW16T, 60.7 mol%, is the lowest yet reported for the genus. 16S rRNA gene sequence analysis placed strain RW16T as an outlier in the genus Sphingobium. The name Sphingobium aromaticiconvertens sp. nov. is proposed for this dibenzofuran-mineralizing organism, with type strain RW16T (=DSM 12677T=CIP 109198T).
    • Sphingomonas fennica sp. nov. and Sphingomonas haloaromaticamans sp. nov., outliers of the genus Sphingomonas.

      Wittich, Rolf-Michael; Busse, Hans-Jürgen; Kämpfer, Peter; Macedo, Alexandre J; Tiirola, Marja; Wieser, Monika; Abraham, Wolf-Rainer; Bereich Mikrobiologie, Helmholtz Zentrum für Infektionsforschung (formerly GBF), D-38124 Braunschweig, Germany. (2007-08)
      Bacterial isolates obtained from polychlorophenol-contaminated sites in Finland (strain K101(T)) and from a Dutch drinking water well (strain A175(T)) were characterized taxonomically. 16S rRNA gene sequence analysis, determination of DNA G+C content, physiological characterization, estimation of the ubiquinone and polar lipid patterns and fatty acid content revealed that strains K101(T) and A175(T) were similar to Sphingomonas wittichii RW1(T) but also showed pronounced differences. The DNA G+C contents of the two novel strains were 63.6 and 66.1 mol%, respectively. On the basis of these results, two novel species of the genus Sphingomonas are described, for which the names Sphingomonas haloaromaticamans sp. nov. [type strain A175(T) (=DSM 13477(T)=CCUG 53463(T))] and Sphingomonas fennica sp. nov. [type strain K101(T) (=DSM 13665(T)=CCUG 53462(T))] are proposed.
    • Three stages of a biofilm community developing at the liquid-liquid interface between polychlorinated biphenyls and water.

      Macedo, Alexandre José; Kuhlicke, Ute; Neu, Thomas R; Timmis, Kenneth N; Abraham, Wolf-Rainer; GBF-National Research Center for Biotechnology, Environmental Microbiology, Mascheroder Weg 1, 38124 Braunschweig, Germany. (2005-11)
      Soil contaminated with polychlorinated biphenyls (PCB) was used as an inoculum to grow a complex biofilm community on PCB oil (Aroclor 1242) on a substratum (Permanox). The biofilm was monitored for 31 days by confocal laser scanning microscopy, community fingerprinting using single-strand conformational polymorphism (SSCP), amplicons of the 16S rRNA genes, and chemical analyses of the PCB congeners. SSCP analysis of the young biofilm revealed a rather diverse microbial community with species of the genera Herbaspirillum and Bradyrhizobium as dominant members. The biofilm developing on the PCB droplets displayed pronounced stages of PCB degradation and biofilm development not described before from pure-culture experiments. The first step was the colonization of the substratum while the PCB oil was hardly populated. When a certain density of bacteria was reached on the Permanox, the PCB was colonized, but soon the degradation of the congeners was markedly reduced and many cells were damaged, as seen by LIVE/DEAD staining. Finally, the biofilm formed aggregates and invaded the PCB oil, showing lower numbers of damaged cells than before and a dramatic increase in PCB degradation. This sequence of biofilm formation is understood as a maturation process prior to PCB oil colonization. This is followed by a thin biofilm on the PCB droplet, an aggregation process forming pockets in the PCB, and finally an invasion of the biofilm into the PCB oil. Only the mature biofilm showed degradation of pentachlorinated PCB congeners, which may be reductively dechlorinated and the resulting trichlorobiphenyls then aerobically metabolized.