Differentiation between Campylobacter hyoilei and Campylobater coli using genotypic and phenotypic analyses

Genotypic and phenotypic methods were applied to investigate differences between the closely related species Campylobacter hyoilei and Campylobacter coli. A unique DNA sequence from C. hyoilei was used to design a specific PCR assay that amplified a DNA product of 383 bp for all C. hyoilei strains, but not other Campylobacter species, including C. coli. The PCR assay could detect 100 fg pure C. hyoilei DNA, 2 x (10)2 c.f.u. ml(-1) using cultured cells and 8.3 x (10)3 c.f.u. 0.1 g(-1)in faeces. The C. hyoilei sequence utilized for specific detection and identification of this species showed similarities to sequences from bacteriophages Mu, P2 and 186, suggesting lysogination of the ancestral C. hyoilei genome. Activities of a set of 15 enzymes that participate in a variety of cellular functions, including biosynthesis, catabolism, energy generation, maintenance of redox balance and phosphate utilization, were tested using sets of strains of C. hyoilei and C. coli. Comparison of mean rates of enzyme activities revealed significant differences between species in the values determined for seven of these activities. Both the genetic and phenotypic data indicate that C. hyoilei is a unique Campylobacter species

Structural and optical properties of SbxSey thin films obtained by chemical molecular beam deposition method from Sb and Se precursors

SbxSey thin-films were obtained by chemical-molecular beam deposition (CMBD) on soda-lime glass from Sb and Se precursors. By the precise control of the Sb/Se ratio, Sb2Se3 thin films with stoichiometric composition were successfully obtained. The elemental and phase composition, as well as the crystal structure of SbxSey thin-films, were studied by energy-dispersive X-ray microanalysis, X-ray diffraction, Raman spectroscopy, scanning electron microscopy and atomic force microscopy. The optical bandgap of the films was determined from the absorption spectra acquired by a spectrophotometer. The physical properties of SbxSey thin films with different compositions were investigated