Search results for "Nostocales"
showing 3 items of 3 documents
’Structural constraints in cyanobacteria-mediated whole-cell biotransformation of methoxylated and methylated derivatives of 2′-hydroxychalcone
2019
Halophilic and freshwater strains of cyanobacteria representing the Oscillatoriales, Nostocales, Chroococcales, and Synechococcales orders of Cyanophyta were examined to determine (i) the resistance of their cultures when suppressed by the presence of exogenous methoxylated and methylated derivatives of 2'-hydroxychalcone, (ii) morphological changes in cells treated with the tested chalcones and, most importantly, (iii) whether these photoautotrophic microorganisms transform chalcone derivatives in a structure- or strain-dependent manner. The growth of cyanobacterial cultures depended on chalcone derivatives and the strain; nevertheless, trends for correlations between these parameters are …
Vertical structure of bi-layered microbial mats from Byers Peninsula, Maritime Antarctica
2013
AbstractA summer study of the vertical structure of bi-layered microbial mats was carried out on Byers Peninsula (Livingston Island, South Shetland Islands). These benthic communities had a common basic structure that consisted of two distinct layers differing in composition, morphology and colour. Our sampling focused on mats showing more layering, which thrived over moist soils and at the bottom of ponds. The photosynthetic pigments analysis performed by high-performance liquid chromatography demonstrated a major occurrence of cyanobacteria and diatoms on these mats, the former being more abundant in relative terms on the surface and composed by morphospecies grouping into orders Oscillat…
Phytoplankton strategies and diversity under different nutrient levels and planktivorous fish densities in a shallow Mediterranean lake
2005
Two mesocosm experiments were carried out to investigate the dynamic effects of nutrients (nitrogen and phosphorus) and planktivorous fish additions on phytoplankton strategies and diversity. The phylogenetic and functional approaches were used to understand phytoplankton ecology in shallow Mediterranean lakes. The experimental approach is new for the study of algal functional groups. Nutrient loading and fish stocks enhanced biomass of small algae but decreased phytoplankton diversity and species richness. Faster species replacement and fluctuations in diversity occurred above loadings of 1 μM P and 21 μM N. Mesotrophic conditions favoured a diverse pool of species, including nostocales an…