During the last 100 years, the neuston bacterium Nevskia ramosa has been described several times. This bacterium forms conspicuous rosette-like microcolonies at the air-water interface. In this study, pure cultures of Nevskia ramosa were obtained for the first time, from a bog lake (strain Soe1, DSMZ 11499T) and a freshwater ditch (strain OL1, DSMZ 11500). The isolates showed special adaptations to life in the epineuston. They formed hydrophobic surface films with a dull appearance. N. ramosa is sensitive to UV radiation but revealed a very effective photorepair mechanism. Exposure to light at a wavelength of 350 nm after UV treatment raised the number of surviving cells by several orders of magnitude. The isolates grew with a broad range of organic substrates. Surface films were formed only in the absence of combined nitrogen; however, nitrogenase activity was not detected. It appears that during growth at the air-water interface the cells benefit from trapping ammonia from the air. The G + C content of the DNA was 67.8 and 69.0 mol% for strains Soe1 and OL1, respectively. The slight difference was confirmed by enterobacterial repetitive intergenic consensus PCR. The 16S rRNA sequences revealed 99.2% similarity. Thus, both isolates belong to the same species. The phylogenetic analysis indicated that Nevskia is a member of the gamma-subclass Proteobacteria that has no known close relatives.
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http://dx.doi.org/10.1128/AEM.64.5.1890-1894.1998 | DOI Listing |
Antonie Van Leeuwenhoek
May 2019
Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
A novel Gram-stain negative, rod-shaped and motile bacterial strain, designated strain Seoho-38, was isolated from a eutrophic lake in South Korea. Polyphasic taxonomic studies were performed to investigate the taxonomic position of the new isolate. The phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain Seoho-38 formed a distinct cluster with Nevskia ramosa Soe1, Nevskia persephonica G6M-30, Nevskia soli GR15-1, Nevskia terrae KIS13-15 and Nevskia aquatilis F2-63 with bootstrap resampling value of 100%.
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August 2018
Department of Chemistry and Bioengineering, Tampere University of Technology, Korkeakoulunkatu 8, 33720 Tampere, Finland.
Background: Microbial biosynthesis of alkanes is considered a promising method for the sustainable production of drop-in fuels and chemicals. Carbon dioxide would be an ideal carbon source for these production systems, but efficient production of long carbon chains from CO is difficult to achieve in a single organism. A potential solution is to employ acetogenic bacteria for the reduction of CO to acetate, and engineer a second organism to convert the acetate into long-chain hydrocarbons.
View Article and Find Full Text PDFMicrob Cell Fact
February 2018
Department of Chemistry and Bioengineering, Tampere University of Technology, Tampere, Finland.
Background: Fatty aldehydes are industrially relevant compounds, which also represent a common metabolic intermediate in the microbial synthesis of various oleochemicals, including alkanes, fatty alcohols and wax esters. The key enzymes in biological fatty aldehyde production are the fatty acyl-CoA/ACP reductases (FARs) which reduce the activated acyl molecules to fatty aldehydes. Due to the disparity of FARs, identification and in vivo characterization of reductases with different properties are needed for the construction of tailored synthetic pathways for the production of various compounds.
View Article and Find Full Text PDFSpringerplus
December 2013
Department of Ichthyology & Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Volos, 384 46 Greece ; Department of Aquaculture & Fisheries Management, Technological Educational Institute of Mesolonghi, Mesolonghi, 30 200 Greece.
We analysed the 16S rRNA gene diversity within the bacterioplankton community in the water column of the ornamental fish Pterophyllum scalare and Archocentrus nigrofasciatus aquaria during a 60-day growth experiment in order to detect any dominant bacterial species and their possible association with the rearing organisms. The basic physical and chemical parameters remained stable but the bacterial community at 0, 30 and 60 days showed marked differences in bacterial cell abundance and diversity. We found high species richness but no dominant phylotypes were detected.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
January 2013
Graduate Program in Ecology and Evolutionary Biology, University of Oklahoma, 660 Parrington Oval, Norman, OK 73019, USA.
A novel bacterial strain designated HA-01(T) was isolated from a freshwater terrestrial hot spring located at Hot Springs National Park, Arkansas, USA. Cells were Gram-negative-staining, rod-shaped, aerobic, chemo-organotrophic, oxidase- and catalase-positive, non-spore-forming and motile by means of a single polar flagellum. Growth occurred at 37-60 °C, with an optimum between 45 and 50 °C, and at pH 6.
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