0000000000114145
AUTHOR
Margarita Ortigosa
Numerical Taxonomy of Aerobic, Gram-negative Bacteria associated with Oysters and Surrounding Seawater of the Mediterranean Coast
Abstract A numerical taxonomic study was performed on 245 strains of heterotrophic, aerobic, marine bacteria, plus 26 reference strains. The isolates were obtained from oysters and seawater sampled monthly over one year, by direct plating on Marine Agar. The strains were characterised by 93 morphological, biochemical, physiological and nutritional tests. Clustering yielded 46 phena at 0.60 S level (S J coefficient). Some could be identified as species of Alteromonas, Shewanella, Deleya, Flavobacterium, Oceanospirillum, Pseudomonas and marine Agrobacterium -like organisms, others were unidentified groups. Several phena seem to correspond to as yet undescribed taxa.
Numerical Taxonomy of Vibrionaceae Isolated from Oysters and Seawater Along an Annual Cycle
Summary A numerical taxonomic study on Gram negative heterotrophic facultative anaerobic bacteria isolated from marine samples (oysters and seawater of Western Mediterranean Sea) was performed. Three hundred sixty eight strains, including reference strains of most species of the Vibrionaceae , were characterized (96 tests per strain). Cluster analysis of similarity matrices obtained with S SM and S J coefficients was performed and S J -based tree and 0.75 S level selected for definition of phena. Larger phena corresponded to non-luminescent Vibrio splendidus biotype 1 and V. harveyi . The species V. tubiashii (an oyster larvae pathogen), V. pelagius, V. mediterranei, V. orientalis and Photo…
Aerobic and facultative anaerobic heterotrophic bacteria associated to Mediterranean oysters and seawater
A comparative study on the composition and seasonal fluctuations of the main heterotrophic bacterial groups and species isolated from Mediterranean oysters and their growing-seawater was carried out. For the study we used 574 strains isolated from Marine Agar (MA) and submitted to numerical analysis of phenotypic traits in previous studies, plus 323 isolates recovered on Thiosulphate Citrate Bile Sucrose (TCBS) agar from the same samples and identified in this study. Oyster samples were dominated by halophilic fermentative bacteria during most of the year with predominance of two Vibrio species, V. splendidus (at temperatures lower than 20°C), and V. harveyi (at higher temperatures). On the…
Vibrio Species in Seawater and Mussels: Abundance and Numerical Taxonomy
Summary Qualitative and quantitative studies were performed on Vibrio species from seawater and mussel samples at a hatchery in Valencia harbour, and from market mussels. Vibrio alginolyticus and V. harveyi were the most abundant species in all samples. Other species identified were V. pelagius, V. mediterranei, V. tubiashii, V. damsella, V. splendidus, V. fluvialis, V. parahaemolyticus, V. anguillarum, V. cholerae and Aeromonas spp . The abundance of V. harveyi and V. mediterranei was positively correlated with temperature whereas V. pelagius counts showed negative correlation with this parameter. The pathogenic species were recovered in very low numbers. A numerical taxonomic study was pe…