Roseomonas lacus sp. nov., isolated from freshwater lake sediment

Abstract

An aerobic, Gram-negative bacterial strain, TH-G33 T , was isolated from freshwater sediment of Taihu Lake in China. The taxonomy of strain TH-G33 T was studied by using phenotypic and phylogenetic methods. Cells of strain TH-G33 T were coccoid rods or rods and formed colourless to pale-pink colonies on nutrient agar. Phylogenetic analysis based on nearly complete 16S rRNA gene sequences showed that strain TH-G33 T was related to Roseomonas mucosa (94?4 %), Roseomonas gilardii subsp. gilardii (94?1 %), Roseomonas gilardii subsp. rosea (94?8 %) and Roseomonas cervicalis (93?9 %). Cells contained ubiquinone 10 (Q-10) as the major quinone and the G+C content was 71?9 mol%. Thus, strain TH-G33 T represents a novel species of the genus Roseomonas, for which the name Roseomonas lacus sp. nov. is proposed. The type strain is TH-G33 T (=CGMCC 1.3617 T =JCM 13283 T ).The genus Roseomonas (Rihs et al., 1993) was created for pink coccoid isolates that caused bacteraemia and other human infections. Roseomonas species have been isolated frequently from blood, wounds, exudates, abscesses and genitourinary specimens (Rihs et al., 1993;Sandoe et al., 1997; Bibashi et al., 2000;Subudhi et al., 2001). Recently, bacterial strains that are phylogenetically related to members of the genus Roseomonas have also been isolated frequently from environmental samples such as drinking water distribution systems (September et al., 2004), oil wells (Roseomonas strain BON 1; GenBank accession no. AY219712), biological soil crust (Roseomonas strain CP4B2; AJ871456), agriculture drainage water (Roseomonas strain SA-2; AY730026), as well as from water (Rihs et al., 1993). Roseomonas-related 16S rRNA gene sequences have also been detected frequently during molecular surveys of microbial diversity in various environments, for example, in the freshwater bacterial communities associated with cyanobacterial blooms in four Swedish lakes (Eiler & Bertilsson, 2004 Strain TH-G33 T was isolated from sediment of the freshwater Taihu Lake (also called lake Tai; 120u 029 16?80 E 31u 279 10?70 N, Jiangsu Province, China), by plating 10-fold dilutions of samples on dilute nutrient medium (DNM) containing (l 21 ): 0?3 g beef extract, 1?0 g fish peptone, 0?1 g yeast extract, 0?5 g NaCl and 15 g agar. Sediment samples were obtained from 10 cm beneath the sediment surface. LB or nutrient medium (NM) agar or broth at 30 u C were used for routine cultivation.Gram reactions were determined by staining cells grown on NM agar at 30 u C for 24 h according to the method described by Gerhardt et al. (1994). Endospore formation was determined after malachite green staining of cells grown on LB agar. Cell flagellation and morphology were examined by using transmission and scanning electron microscopy. For assimilation of carbon sources, the standard mineral base solution of Stanier et al. (1966) was used. Each compound was added at a concentration of 0?2 % (w/v) after the mineral base solution had been autoclaved. Growth was examined after incubation at 30 uC for 1, 3, 7 and...

Characteristics of a Pink‐Pigmented Bacterium Isolated from Biofilm in a Cooling Tower in Tokyo, Japan

“…As with other members of the genus Roseomonas (3, 5, 9), the major quinone is ubiquinone-10 (Q-10). The DNA GϩC content of strain K-20 was 72.0 mol%, the value resembling that of R. lacus (5).…”

Roseomonas stagni sp. nov., isolated from pond water in Japan

“…As with other members of the genus Roseomonas (Gallego et al, 2006;Jiang et al, 2006;Odugbemi et al, 1988;Yoon et al, 2007), the predominant quinone of strain HS-69 T was ubiquinone-10 (Q-10). The DNA G+C content of strain HS-69 T was 72.0 mol%, which was similar to that of R. lacus (Jiang et al, 2006). Strain HS-69 T was susceptible to ABPC (MIC 0.016 μg/ml), AZM (MIC=0.125 μg/ml), MINO (MIC 0.016 μg/ml), TC (MIC=0.064 μg/ml), CP (MIC=0.125 μg/ ml), IPM (MIC=0.008 μg/ml), MEPM (MIC 0.002 μg/ ml), CPFX (MIC=0.008 μg/ml), OFLX (MIC=0.016 μg/ ml), and SPFX (MIC 0.002 μg/ml) and resistant to CXM (MIC 256 μg/ml), VCM (MIC 256 μg/ml), and FOM (MIC 1,024 μg/ml).…”

“…Roseomonas species have been isolated from clinical specimens (Han et al, 2003;Lewis et al, 1997;Sandoe et al, 1997;Subudhi et al, 2001;Vasallo et al, 1998) and some species are considered to cause opportunistic infections in humans. Recently, Roseomonas species have also been isolated frequently from various natural environments, including aqueous environments (Gallego et al, 2006), indicating that members of the genus Roseomonas are widely distributed in nature (Jiang et al, 2006). In this report, we describe the phenotypic and phylogenetic characteristics of a Roseomonas strain, HS-69 T , isolated from pond water, and propose that HS-69 T is classified as a novel species.…”

“…gilardii (Han et al, 2003) but differed from those of R. aquatica (Gallego et al, 2006) and R. lacus (Jiang et al, 2006). As with other members of the genus Roseomonas (Gallego et al, 2006;Jiang et al, 2006;Odugbemi et al, 1988;Yoon et al, 2007), the predominant quinone of strain HS-69 T was ubiquinone-10 (Q-10). The DNA G+C content of strain HS-69 T was 72.0 mol%, which was similar to that of R. lacus (Jiang et al, 2006).…”

Roseomonas tokyonensis sp. nov. Isolated from a Biofilm Sample Obtained from a Cooling Tower in Tokyo, Japan

“…Roseomonas species have also b e e n f re q u e n t l y i s o l a t e d f ro m v a r i o u s n a t u r a l environments Jiang et al, 2006;Yoo et al, 2008;Zhang et al, 2008;Venkata Ramana et al, 2010 , including aqueous environments Gallego et al, 2006;Furuhata et al, 2008;Kim et al, 2009 , indicating that members of the genus Roseomonas are widely distributed in natural environments.…”