This study reports the antibiotic resistance patterns of coagulase negative staphylococci (CNS) isolated from a drinking water treatment plant (WTP), a drinking water distribution network, responsible for supplying water to the consumers (WDN), and a wastewater treatment plant (WWTP), responsible for receiving and treating domestic residual effluents. Genotyping and the 16S rRNA gene sequence analysis demonstrated a higher diversity of species both in the WTP (6 species/19 isolates) and WWTP (12 species/47 isolates) than in the WDN (6 species/172 isolates). Staphylococcus pasteuri and Staphylococcus epidermidis prevailed in the WTP and WDN and Staphylococcus saprophyticus in the WWTP. Staphylococci with reduced susceptibility (resistance or intermediary phenotype) to beta-lactams, tetracycline, clindamycin and erythromycin were observed in all types of water and belonged to the three major species groups. The highest resistance rate was found against erythromycin, presumably due to the presence of the efflux pump encoded by the determinant msrA, detected in the majority of the resistant isolates. This study demonstrates that antibiotic resistant CNS may colonize different types of water, namely drinking water fulfilling all the quality standards.
Two adjacent paddies of an experimental rice field, subjected to organic and conventional farming, were characterized aiming the comparative assessment of microbiological variations occurring in the bulk paddy soil over the rice cycle. This study comprehended the simultaneous characterization of general physicochemical soil properties [total carbon and nitrogen, pH (H 2 O and KCl), C:N ratio and water content], biochemical properties [enzymatic activities and Community Level Physiological Profiles (CLPP)], the estimation of cultivable organisms (enumeration of fast growing heterotrophic bacteria, actinomycetes and fungi) and the assessment of bacterial diversity using a culture-independent method (PCR-DGGE fingerprinting). The linkage of the parameters measured was analysed by canonical correspondence analysis (CCA). CCA ordination plots of the CLPP showed a similar pattern of microbial functional activity in both agronomic management systems, except in June. Enzymatic activity, water content and fungi counts were the main factors affecting the observed CLPP time variation. Such a variation was not expressed by the Shannon and evenness indices, which did not evidence significant differences in the bacterial and functional diversity between or within farming type over the analysed period. The cluster and CCA analyses of the DGGE profiles allowed the distinction of the bacterial communities of both paddies, with temporal variations being observed in the organically managed field but not in the conventional paddy. Enzymatic activity, pH and molinate content were the factors which most contributed to the observed variations. Altogether these results underline the functional redundancy of the rice paddy soil and evidence the temporal variations on the metabolic activity of soil, irrespective of farming type.
Two bacterial strains, PC-142 and PC-147 T , isolated from poultry litter compost, were characterized with respect to their phenetic and phylogenetic characteristics. The isolates were endospore-forming rods that were reddish in colour after Gram staining. They were catalaseand oxidase-positive, were able to degrade starch and gelatin and grew at 15-40 6C and pH 5.5-10.0. The predominant fatty acids were anteiso-C 15 : 0 , iso-C 15 : 0 and iso-C 16 : 0 , the major respiratory quinone was menaquinone MK-7, the cell-wall peptidoglycan was of the A1c type and the G+C content of the DNA was 58 mol%. The 16S rRNA gene sequence analysis and phenetic characterization indicated that these organisms belong to the genus Paenibacillus, with Paenibacillus pasadenensis SAFN-007 T as the closest phylogenetic neighbour (97.5 %).
A bacterium, designated strain DC-196 T , isolated from kitchen refuse compost was analysed by using a polyphasic approach. Strain DC-196 T was characterized as a Gram-negative short rod that was catalase-and oxidase-positive, and able to grow at 10-40 6C, pH 6-9 and in NaCl concentrations as high as 3 %. Chemotaxonomically, C 18 : 1 was observed to be the predominant cellular fatty acid and ubiquinone 10 (Q10) was the predominant respiratory quinone. The G+C content of the genomic DNA was determined to be 66 mol%. On the basis of the genotypic, phenotypic and chemotaxonomic characteristics, strain DC-196 T was assigned to the genus Shinella, although with distinctive features. At the time of writing, 16S rRNA gene sequence similarities of 97.6-96.8 % and the low DNA-DNA hybridization values of 38.2-32.2 % with the type strains of the three recognized Shinella species confirmed that strain DC-196 T represents a novel species of the genus, for which the name Shinella fusca sp. nov. is proposed (type strain DC-196 T 5CCUG 55808 T 5LMG 24714 T ).
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