SARS-CoV-2 spike protein: flexibility as a new target for fighting infection

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Large-Scale Distribution of the European Seahorses (Hippocampus Rafinesque, 1810): A Systematic Review

Human pressures on marine ecosystems have caused extensive degradation of marine habitats and several local extinctions. Overexploitation and destructive fishing practices are responsible for biodiversity loss in many coastal ecosystems. The definition of conservation programs in marine fish requires comprehensive knowledge on large-scale geographical distribution, while considering distribution/abundance patterns in relation to key environmental variables. Due to their life-cycle traits, the two European seahorses (Hippocampus guttulatus and H. hippocampus), as with other congeneric species, are particularly sensitive to the effects of anthropogenic activities and habitat changes. However, information on the ecological distribution of these two species is scattered, patchy, and mainly focused on small-scale studies. In this paper, we followed an international standard protocol for systematic reviews (the PRISMA protocol) to provide a detailed assessment of the two species’ geographical distribution in relation to the environmental characteristics. According to the 134 analyzed studies, Hippocampus guttulatus is more common in confined areas, while H. hippocampus is found in marine shelf waters. With several interspecific differences, seagrasses were the most used holdfasts of both species. The EUNIS codes (European nature information system) referring to a specific and unique habitat were discussed as a potential tool for defining the ecological distribution of the two species. The obtained results and their future implementation could help plan conservation actions

Two cases study of fouling colonization patterns in the Mediterranean Sea in the perspective of integrated aquaculture systems

Fouling assemblage colonizing fish-farms is considered mostly to produce negative impacts causing financial loss. By contrast, large evidences emerged on the bioremediation role by biofouling associated to aquaculture facilities, even if the fouling assemblages thriving in the water column was poorly investigated. The aim of the present work was to investigate the macrofouling assemblages over one year of immersion, in order to single out the fouling species, which play the most remarkable role for the bioremediation of the marine areas affected by aquaculture activities. With this in mind, we studied the fouling community dynamics in two Mediterranean maricultural facilities, respectively in the Mar Grande of Taranto (Ionian Sea) and in the Gulf of Gaeta (Tyrrhenian Sea), using the same experimental design and time frame. Two experiments were carried out using artificial panels anchored to two finfish cages. The one-year old fouling communities in the two sites were compared at four seasons of immersion, four submersion durations and three depths, both communities from structural and functional points of view. Notwithstanding the quite similar species composition of fouling of the two sites, the biofouling showed the highest biodiversity in the Mar Grande of Taranto. In the Gulf of Gaeta mussels, Mytilus galloprovincialis, dominated at all the times and depths, whilst in the Mar Grande of Taranto they were especially abundant at the surface with the deepest panels being largely colonized by polychaete sabellids. The co-occurrence of the filter-feeders Mytilus-sabellids recorded in the Gulf of Taranto also highlighted the highest filtration capability. Our results suggest two different fouling assemblages as candidates for bioremediation in integrated multitrophic aquaculture facilities: both a monospecific system dominated by mussels and a multi-specific system with sabellids and mussels as most abundant filter-feeders

Protein structure analysis of the interactions between SARS-CoV-2 spike protein and the human ACE2 receptor: from conformational changes to novel neutralizing antibodies

The recent severe acute respiratory syndrome, known as Coronavirus Disease 2019 (COVID-19) has spread so much rapidly and severely to induce World Health Organization (WHO) to declare a state of emergency over the new coronavirus SARS-CoV-2 pandemic. While several countries have chosen the almost complete lock-down for slowing down SARS-CoV-2 spread, the scientific community is called to respond to the devastating outbreak by identifying new tools for diagnosis and treatment of the dangerous COVID-19. With this aim, we performed an in silico comparative modeling analysis, which allows gaining new insights into the main conformational changes occurring in the SARS-CoV-2 spike protein, at the level of the receptor-binding domain (RBD), along interactions with human cells angiotensin-converting enzyme 2 (ACE2) receptor, that favor human cell invasion. Furthermore, our analysis provides (1) an ideal pipeline to identify already characterized antibodies that might target SARS-CoV-2 spike RBD, aiming to prevent interactions with the human ACE2, and (2) instructions for building new possible neutralizing antibodies, according to chemical/physical space restraints and complementary determining regions (CDR) mutagenesis of the identified existing antibodies. The proposed antibodies show in silico high affinity for SARS-CoV-2 spike RBD and can be used as reference antibodies also for building new high-affinity antibodies against present and future coronaviruses able to invade human cells through interactions of their spike proteins with the human ACE2. More in general, our analysis provides indications for the set-up of the right biological molecular context for investigating spike RBD–ACE2 interactions for the development of new vaccines, diagnostic kits, and other treatments based on the targeting of SARS-CoV-2 spike protein

Filtering activity and nutrient release by the keratose sponge sarcotragus spinosulus schmidt, 1862 (Porifera, demospongiae) at the laboratory scale

Sponges are an important constituent of filter-feeder benthic communities, characterized by high ecological plasticity and abundance. Free bacteria constitute an important quota of their diet, making them excellent candidates in aquaculture microbial bioremediation, where bacteria can be a serious problem. Although there are studies on this topic, certain promising species are still under investigation. Here we report applied microbiological research on the filtering activity of Sarcotragus spinosulus on two different concentrations of the pathogenic bacterium Vibrio para-haemolyticus in a laboratory experiment. To evaluate the effects of the filtration on the surrounding nutrient load, the release of ammonium, nitrate, and phosphate was also measured. The results obtained showed the efficient filtration capability of S. spinosulus as able to reduce the Vibrio load with a maximum retention efficiency of 99.72% and 99.35% at higher and lower Vibrio concentrations, respec-tively, and remarkable values of clearance rates (average maximum value 45.0 ± 4.1 mL h−1 g DW−1 ) at the highest Vibrio concentration tested. The nutrient release measured showed low values for each considered nutrient category at less than 1 mg L−1 for ammonium and phosphate and less than 5 mg L−1 for nitrate. The filtering activity and nutrient release by S. spinosulus suggest that this species represents a promising candidate in microbial bioremediation, showing an efficient capability in removing V. parahaemolyticus from seawater with a contribution to the nutrient load

Technology to enable new paradigms of teaching/learning in mathematics: the digital interactive storytelling case

This paper concerns the design and implementation of a particular methodology for mathematics teaching/learning which exploits an interactive and immersive metaphor of storytelling. This research aims to promote processes such as inquiring, conjecturing, formalizing, proving in mathematics, and to investigate which is the best way to organize ICT tools to achieve that purpose. We also report the findings of an ongoing experimentation at the K12 school level

First description of early developmental stages of the native invasive fireworm Hermodice carunculata (Annelida, Amphinomidae): A cue to the warming of the mediterranean sea

Observations on the reproductive behavior and larval development of the bristled fireworm Hermodice carunculata, a common inhabitant of shallow marine rocky bottoms in the Southern Mediterranean Sea, are reported here. In recent years, an increase in abundance and a northward expansion of the populations along the Southern Italian coast were jointly detected, presumably linked to rising water temperature in the Mediterranean Sea. After making in situ observations on two consecutive spawning events, live worms and fresh spawn were brought into the lab, kept at either 27°C or 22°C and followed through development. Complete and normal development was observed only at 27°C. By contrast, embryonic and larval development appeared to be slowed down at 22°C, stopping at the protrochophora stage. Early development of H. carunculata suggests the existence of a long pre-metamorphic, planktotrophic period in the water column that can explain the genetic cohesion of this species and the low genetic divergence found among populations across the Atlantic Ocean. The observed increase in abundance, invasiveness potential, and geographical northern distribution of the bearded fireworms is probably determined by a progressive northward latitudinal shift of the sea surface temperature coincident with the temperature threshold required for the developmental and reproductive success of the worm