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Trento, Italy

Mares J.,Institute of Hydrobiology | Mares J.,CAS Institute of Botany | Mares J.,University of South Bohemia | Cantonati M.,Museo delle Science MUSE
Fottea | Year: 2016

Over the last decades, the taxonomy of cyanobacteria has been considerably improved and restructured due to the increase in data output from molecular phylogeny. Recently, a new protocol was developed that enables reliable sequencing of 16S rRNA genes in cultivation–resistant cyanobacteria using analysis of single cells, filaments, or colonies. In the current study, we examined a sample of a heteropolar unicellular cyanobacterium, Geitleribactron purpureum, from the holotype material (deep epilithon of Lake Tovel, Western Dolomites, Italy). We isolated and purified single colonies of G. purpureum, and subjected them to direct PCR and 16S rRNA gene sequencing. We obtained a congruent set of sequences that formed a unique, isolated cyanobacterial lineage, showing phylogenetic clustering among simple filamentous genera of the family Leptolyngbyaceae. We provide evidence for deep polyphyly in Chamaesiphonaceae, and suggest that Geitleribactron should be re–classified in the Leptolyngbyaceae. © Czech Phycological Society (2016).

Svalastog A.L.,Uppsala University | Martinelli L.,Museo delle Science MUSE
Croatian Medical Journal | Year: 2013

The immortal HeLa cells case is an intriguing example of bio-objectification processes with great scientific, social, and symbolic impacts. These cells generate questions about representation, significance, and value of the exceptional, variety, individuality, and property. Of frightening (a lethal cancer) and emarginated (a black, poor woman) origins, with their ability to "contaminate" cultures and to "spread" into spaces for becoming of extraordinary value for human knowledge, well-being, and economy advancements, HeLa cells have represented humanity, and emphasized the importance of individual as a core concept of the personalized medicine. Starting from the process leading from HeLa "cells" to HeLa "bio-objects," we focus on their importance as high quality bio-specimen. We discuss the tension between phenomenological characteristic of fundamental biological research and the variety of material and methodologies in epidemiology and personalized medicine. The emerging methodologies and societal changes reflect present EU policies and lead toward a new paradigm of science.

Cantonati M.,Museo delle Science MUSE | Metzeltin D.,Am Stegskreuz 3b | Soninkhishig N.,National University of Mongolia | Lange-Bertalot H.,Goethe University Frankfurt
Phytotaxa | Year: 2016

The stalked diatom Didymosphenia is being thoroughly studied because it can cause serious nuisance blooms. The species most commonly involved is D. geminata. Although Didymosphenia species occur in running waters and lakes, published reports generally refer to lotic habitats. Given the applied interest in Didymosphenia, as well as its suitability for fundamental ecological studies, here we report an observation of a Didymosphenia bloom occurring on the southern part of the eastern shore of the large oligotrophic Lake Hövsgöl (Mongolia). LM and SEM observations revealed that the bloom was formed by Didymosphenia laticollis. The bloom extended for a long stretch of the eastern shore whilst on the opposing lake margin no bloom was visible, where a different Didymosphenia species was collected (D. mongolica). We interpreted the Lake Hövsgöl D. laticollis bloom in light of the most updated knowledge on Didymosphenia blooms ecophysiology. Lake Hövsgöl meets all main environmental requirements for Didymosphenia bloom formation: conditions are oligotrophic and phosphorus is the limiting factor, waters are very transparent and benthic light availability is consequently high, alkalinity is relatively high, and stable rocky substrata in a hydrologically-turbulent environment are widespread. The light-brown color of the bloom is in good agreement with experimental results suggesting that low-SRP conditions promote bloom formation in the presence of high light and alkalinity, because energy is converted to stalk material (the primary site of alkaline phosphatase production in Didymosphenia) rather than in cells. We speculate that the occurrence of the bloom on the eastern shore and its absence on the western shore might depend upon morphology, land use, and climate change causing alkalinity and organic phosphate inputs on the eastern side. © 2016 Magnolia Press.

Cantonati M.,Museo delle Science MUSE | Segadelli S.,Emilia Romagna Region | Segadelli S.,University of Parma | Ogata K.,University of Parma | And 7 more authors.
Science of the Total Environment | Year: 2016

Springs are biodiversity hotspots and unique habitats that are threatened, especially by water overdraft. Here we review knowledge on ambient-temperature (non-geothermal) freshwater springs that achieve sufficient oversaturation for CaCO3 -by physical CO2 degassing and activity of photoautotrophs- to deposit limestone, locally resulting in scenic carbonate structures: Limestone-Precipitating Springs (LPS). The most characteristic organisms in these springs are those that contribute to carbonate precipitation, e.g.: the mosses Palustriella and Eucladium, the crenophilous desmid Oocardium stratum, and cyanobacteria (e.g., Rivularia). These organisms appear to be sensitive to phosphorus pollution. Invertebrate diversity is modest, and highest in pools with an aquatic-terrestrial interface. Internationally, comprehensive legislation for spring protection is still relatively scarce. Where available, it covers all spring types. The situation in Europe is peculiar: the only widespread spring type included in the EU Habitat Directive is LPS, mainly because of landscape aesthetics. To support LPS inventorying and management to meet conservation-legislation requirements we developed a general conceptual model to predict where LPS are more likely to occur. The model is based on the pre-requisites for LPS: an aquifer lithology that enables build-up of high bicarbonate and Ca2+ to sustain CaCO3 oversaturation after spring emergence, combined with intense groundwater percolation especially along structural discontinuities (e.g., fault zones, joints, schistosity), and a proper hydrogeological structure of the discharging area. We validated this model by means of the LPS information system for the Emilia-Romagna Region (northern Italy). The main threats to LPS are water diversion, nutrient enrichment, and lack of awareness by non-specialized persons and administrators. We discuss an emblematic case study to provide management suggestions. The present review is devoted to LPS but the output of intense ecological research in Central Europe during the past decades has clearly shown that effective conservation legislation should be urgently extended to comprise all types of spring habitats. © 2016 Elsevier B.V.

Cantonati M.,Museo delle Science MUSE | Spitale D.,Museo delle Science MUSE | Scalfi A.,Museo delle Science MUSE | Guella G.,University of Trento
Fottea | Year: 2016

Most studies on springs assumed stability, and reduced seasonal changes in the biota. We focused on two macroalgae (the rhodophyte Hildenbrandia rivularis and the chrysophyte Hydrurus foetidus) to unveil their seasonal–development patterns in springs. H. rivularis cover remained virtually constant throughout the year, although seasonal fluctuations in ecophysiological parameters were detected. The most important determinant of seasonal changes in H. rivularis was shown to be the complex interplay between solar radiation (day length) and shading. Negative cross–correlation between Chl–a and shading was found to be significant but with a time lag. H. foetidus seasonal changes were evident both at the macroscopic level and in ecophysiological parameters. Interestingly, it occurred throughout the year in the spring whilst it completely disappeared in summer in a nearby glacial stream. Unexpectedly, variability of ecophysiological parameters (coefficients of variation) was shown to be 15–20% higher in H. rivularis than in H. foetidus. © Czech Phycological Society (2016).

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