| 1. |
- Ferreira da Silva, Eduardo, et al.
(författare)
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Heavy metal pollution downstream the abandoned Coval da Mó mine (Portugal) and associated effects on epilithic diatom communities
- 2009
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 407:21, s. 5620-5636
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Tidskriftsartikel (refereegranskat)abstract
- This study examined trace-element concentrations in 39 sediment samples collected in the vicinity of the abandoned Coval da Mó mine, and evaluated the anthropogenic contaminant effects and other environmental variables in the taxonomic composition, structure and morphological changes of benthic diatom communities.The results show the existence of extremely high contamination in Pb, Zn and Cd (the mean values exceed the background values 376, 96 and 19 times, respectively) on the first 2.5 km in the water flow direction. Also Co, Cu, Mn and Ni are present in high concentrations. Dilution by relatively uncontaminated sediment reduces metal concentrations downstream, but Zn concentrations increase downstream Fílvida stream, as a result of several factors such as sewage and agriculture.To evaluate the biological effects caused by Pb, Cd and Zn, three sites were selected. In the stressed environment, near the mining area (C232), diatoms were extremely rare, however there was a slight recovery at site C79 located 2 km downstream. Fragilaria capucina var. rumpens, Fragilaria cf. crotonensis and Achnanthidium minutissimum showed abnormal valves which may be related to high levels of metals.Six km downstream, in Fílvida stream (C85), an increase in species richness and diversity was registered while the relative percentage of valve teratologies was lower. In the absence of OM, nutrients and low pH the diatom community patterns must be attributed to the metal concentration at some sites. Considering that community diversity can be affected by abiotic and biotic variables and valve deformations are caused by a small number of variables, basically metals, and acid conditions, we consider the presence of teratologies as an indication of the presence of metals.
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| 2. |
- Vaz-Moreira, Ivone, et al.
(författare)
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Microbacterium luticocti sp. nov., isolated from sewage sludge compost.
- 2008
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Ingår i: International journal of systematic and evolutionary microbiology. - : Microbiology Society. - 1466-5026 .- 1466-5034. ; 58:7, s. 1700-1704
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Tidskriftsartikel (refereegranskat)abstract
- Strain SC-087B(T), isolated from sewage sludge compost during a study of bacterial diversity in composts, was characterized. The isolate was a Gram-positive, short rod that was motile, catalase- and oxidase-negative and able to grow at 27-45 degrees C, pH 5.5-9.7 and in up to 10 % NaCl. The peptidoglycan was of the B2beta type, containing the characteristic amino acids ornithine, homoserine and hydroxyglutamic acid. The muramic acid residues of the peptidoglycan were partially glycolylated. The major cell-wall sugar was mannose; traces of xylose were also detected. The predominant fatty acids, comprising more than 70 % of the total, were anteiso-C(17 : 0) and anteiso-C(15 : 0), the major respiratory quinone was menaquinone-12 (MK-12) and the G+C content of the genomic DNA was 72 mol%. Based on analysis of the 16S rRNA gene sequence, the closest phylogenetic neighbours of strain SC-087B(T) were members of the family Microbacteriaceae, showing sequence similarity values of around 96 % with members of the species Microbacterium barkeri (96.0 %), Microbacterium gubbeenense (95.6 %) and Microbacterium indicum (95.7 %). The chemotaxonomic and phenotypic traits analysed supported the inclusion of this strain within the genus Microbacterium and the proposal of a novel species. The name Microbacterium luticocti sp. nov. is proposed and the type strain is SC-087B(T) (=DSM 19459(T)=CCUG 54537(T)).
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| 3. |
- Vaz-Moreira, Ivone, et al.
(författare)
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Sphingobium vermicomposti sp. nov., isolated from vermicompost.
- 2009
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Ingår i: International journal of systematic and evolutionary microbiology. - : Microbiology Society. - 1466-5026 .- 1466-5034. ; 59:12, s. 3145-3149
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Tidskriftsartikel (refereegranskat)abstract
- Strain VC-230(T) was isolated from homemade vermicompost produced from kitchen waste. The isolate was a Gram-negative-staining, catalase- and oxidase-positive, motile rod-shaped bacterium able to grow at 15-37 degrees C and pH 6-8. On the basis of 16S rRNA gene sequence analysis, strain VC-230(T) was determined to belong to the family Sphingomonadaceae by its clustering with type strains of the genus Sphingobium, with Sphingobium chlorophenolicum ATCC 33790(T) (97.7 %) and Sphingobium herbicidovorans DSM 11019(T) (97.4 %) as its closest neighbours. The polar lipid pattern, the presence of spermidine and ubiquinone 10, the predominance of the cellular fatty acids C(18 : 1)omega7c/9t/12t, C(16 : 1)omega7c and C(16 : 0) and the G+C content of the genomic DNA supported the affiliation of this organism to the genus Sphingobium. The phylogenetic, chemotaxonomic, phenotypic and DNA-DNA hybridization analyses verify that strain VC-230(T) represents a novel species, for which the name Sphingobium vermicomposti sp. nov. is proposed. The type strain is VC-230(T) (=CCUG 55809(T) =DSM 21299(T)).
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