Isolation, identification, and characterization of Vibrio cholerae from the Danube River in Slovakia

ABSTRACT Vibrio cholerae is a facultative human pathogen. In its aquatic habitat and as it passes through the digestive tract, V. cholerae must cope with fluctuations in salinity. We analyzed the genome-wide transcriptional profile of V. cholerae grown at different NaCl concentrations and determined that the expression of compatible solute biosynthesis and transporter genes, virulence genes, and genes involved in adhesion and biofilm formation is differentially regulated. We determined that salinity modulates biofilm formation, and this response was mediated through the transcriptional regulators VpsR and VpsT. Additionally, a transcriptional regulator controlling an osmolarity adaptation response was identified. This regulator, OscR (osmolarity controlled regulator), was found to modulate the transcription of genes involved in biofilm matrix production and motility in a salinity-dependent manner. oscR mutants were less motile and exhibited enhanced biofilm formation only under low-salt conditions.

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Preliminary Characterization of Wild Grapevine Populations (Vitis vinifera ssp. sylvestris) Grown Along the Danube River

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha4129317 ◽

2013 ◽

Vol 41 (2) ◽

pp. 472 ◽

Cited By ~ 3

Author(s):

Carmen F. POPESCU ◽

Liviu C. DEJEU ◽

Rafael R. OCETE

Keyword(s):

Vitis Vinifera ◽

Morphological Analysis ◽

Danube River ◽

Vitis Vinifera L ◽

Meristematic Tissue ◽

The Danube River ◽

Wild Grapevine ◽

The Moment

The individuals belonging to three different groups of wild grapevines populations Vitis vinifera L. ssp. sylvestris (Gmelin) Hegi harvested along, or near the Danube River, were described by means of usual ampelographic methods. The twenty standardized descriptors used for morphological analysis revealed obvious differentiation among analyzed populations. Out of 65 individuals, a half produced flowers with separate sex and a high proportion of them were males (70%). Pollen measurements on light microscope provided information on differences in pollen size among inside wild grapevine populations of V. sylvestris with the polar length varying between 15.3 and 23 Î¼m and the equatorial length between 15.5 and 24.4Î¼m. The in vitro regenerative potential from meristematic tissue tested with each phenotype showed that the moment of differentiation, the aspect of proliferative structures and the rate of multiplication varied inside these wild grapevine populations, without any correlation with the location of harvesting. Our results provided valuable information about these Vitis vinifera ssp. sylvestris populations, possible to be used as starting plant material for research in general and further breeding of cultivars and grapevine rootstocks.

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Hydrogeochemical and isotopic characterization of groundwater at Žitný Island (SW Slovakia)

Hydrology Research ◽

10.2166/nh.2015.187 ◽

2015 ◽

Vol 46 (6) ◽

pp. 929-942 ◽

Cited By ~ 1

Author(s):

Z. Ženišová ◽

P. P. Povinec ◽

A. Šivo ◽

R. Breier ◽

M. Richtáriková ◽

...

Keyword(s):

Chemical Composition ◽

Surface Water ◽

Danube River ◽

Water Isotopes ◽

Anthropogenic Contamination ◽

The Danube River ◽

The Core ◽

Groundwater Reservoir ◽

Isotopic Characterization

Hydrogeochemical investigations and spatial variations studies on the distribution of water isotopes and radiocarbon in the groundwater of Žitný Island (Rye Island) were carried out. Žitný Island represents the largest groundwater reservoir in Central Europe (about 10 Gm3). The chemical composition of the groundwater of Žitný Island depends mainly on the chemical composition of Danube water, as well as on the length of its infiltration from the Danube River. The groundwater is characterized by potamogenic mineralization, and its chemical composition is influenced by anthropogenic contamination. Sub-surface water profiles showed enriched δ18O levels up to around 20 m water depth, and depleted values for deeper waters. The observed isotopic composition of the groundwater is similar to Danube water, suggesting that the Danube River is the main source of the Žitný Island groundwater. The core of the sub-surface 14C profile represents contemporary groundwater with 14C values above 80 pMC.

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