In batch cultures of four Mediterranean strains (from France, Italy, and Spain) of Alexandrium catenella (Whedon et Kof.) Balech growing on a daily light cycle, ammonium and urea uptake were estimated by the (15) N tracer technique. Ammonium uptake could be described by Michaelis-Menten kinetics along a substrate gradient of 0.1-10 μgat N · L(-1) for the four strains, while two different patter...

A substantial proportion of bacteria from five Alexandrium cultures originally isolated from various countries produced sodium channel blocking (SCB) toxins, as ascertained by mouse neuroblastoma assay. The quantities of SCB toxins produced by bacteria and dinoflagellates were noted, and the limitations in comparing the toxicities of these two organisms are discussed. The chemical nature of the...

Non-random usage of synonymous codons, known as “codon bias”, has been described in many organisms, from bacteria to Drosophila, but little is about it phytoplankton. This phenomenon thought be driven by selection for translational efficiency. As the efficacy proportional effective population size, species with large sizes, such phytoplankton, are expected have strong codon bias. To test this, ...

Eutrophication determines algal blooms and the subsequent accumulation of organic matter in sediments, which, turn, results dominance anaerobic respiratory processes that release toxic gases. Dystrophy is a final dissipative moment reduces load sediment. A case dystrophy occurring Burano lagoon (Tuscany, Italy) 2021 reported. The study examined weather, physico-chemistry water, submerged vegeta...

Many corals form obligate symbioses with photosynthetic dinoflagellates of the genus Symbiodinium Freudenthal (1962). These symbionts vary genotypically, with their geographical distribution and abundance dependent upon host specificity and tolerance to temperature and light variation. Despite the importance of these mutualistic relationships, the physiology and ecology of Symbiodinium spp. rem...

For the dinoflagellates, an important group of single-cell protists, some nuclear rDNA phylogenetic studies have reported the discovery of rDNA pseudogenes. However, it is unknown if these aberrant molecules are confined to free-living taxa or occur in other members of the group. We have cultured a strain of symbiotic dinoflagellate, belonging to the genus Symbiodinium, which produces three dis...