Biology subjects

Desiderato, A.

Publications and source records attributed to Desiderato, A..

6 recordsLinked to original sources

bioRxiv2025

Real-time Malaria Detection in the Amazon Rainforest via Drone-Collected eDNA and Portable qPCR

Emerging zoonotic parasites such as Plasmodium spp. in remote ecosystems demand rapid, field-deployable surveillance. We developed a drone-based environmental DNA (eDNA) sampling approach integrated with a portable quantitative PCR (qPCR) assay for in situ detection of Plasmodium DNA. Field trials confirmed malaria parasite DNA in canopy swabs, coinciding spatially with acoustic detection of howler monkeys (Alouatta sp.), suspected reservoir hosts. No Anopheles mosquitoes were captured in simultaneously deployed insect traps. The end-to-end workflow, from drone deployment to diagnostic readout, averaged 1.5 hours per assay, required only basic mobile-laboratory infrastructure, and bypassed cold-chain logistics. This rapid, non-invasive method delivers actionable surveillance data in real-time, enabling near-real-time trigger points for vector-control interventions and clinical response in remote settings. By merging environmental genomics with portable diagnostics, we establish a scalable One Health framework adaptable to diverse vector-borne parasites and ecosystems, with potential for early detection and spillover risk mitigation in under-monitored, high-risk environments.

molecular biology↗

bioRxiv2023

Cold, but not for long enough: first insights into the tolerance to subzero temperatures of the invasive amphipod Dikerogammarus villosus

Dikerogammarus villosus is an invasive Ponto-Caspian amphipod, known to have colonized most of the major European freshwater bodies in the last few decades. Several studies assessing its tolerance related to higher temperatures have been performed; however, no records are present about its response to subzero temperatures. Therefore, in this study, we wanted to experimentally assess for the first time the tolerance of D. villosus to temperatures below 0{degrees}C. The animals were exposed to 0{degrees}C, -8{degrees}C, and room temperature for 2 and 24 hours, tracking their possible movements during the ice melting. Only long exposures at -8{degrees}C appeared to be fatal. These results provide new insights for more accurate predictive models regarding the future expansion of this invader.

ecology↗

bioRxiv2023

From microbial communities to regional biogeography: Unraveling patterns, determinants and the influence of bottom trawling in benthic microbiota

Microbial composition and diversity in marine sediments are shaped by environmental, biological, and anthropogenic processes that operate on different scales. However, our understanding of benthic microbial biogeography remains limited. Here, we study how benthic microbiota vary at a regional scale in the North Sea with sediment characteristics, temperature, organic matter content, shear bed stress and bottom trawling intensity, a prevalent industrial fishing practice which heavily impacts benthic ecosystems. Using 16S rDNA amplicon sequencing, we characterized benthic microbiota from the top centimeter of 349 sediment samples and used uni-and multivariate statistical models, accounting for spatial autocorrelation, to disentangle the effects of the different predictors. Fitted models demonstrate how the geographic interplay of different environmental anthropogenic drivers shapes the structure and functioning of benthic microbial communities. Sediment properties were the primary determinants, with diversity increasing with sediment permeability but at the same time increasing with mud content, highlighting different underlying processes. Alpha diversity also increased nonlinearly with total organic matter content and temperature and showed a more complex relationship with bottom shear stress but decreased with bottom trawling intensity. These trawling associated diversity changes were accompanied by shifts in functional groups related to energy metabolism. Specifically, with increasing trawling intensity, we observed a transition toward more aerobic heterotrophic and less denitrifying metabolism. Our findings provide first insights of benthic microbial biogeographic patterns on a large spatial scale and illustrate how anthropogenic activity such as bottom trawling may influence the distribution and abundances of microbes and overall benthic metabolism at macroecological scales.

ecology↗

bioRxiv2021

Molecular evidence for sweeping discontinuity between peracarid (Crustacea) fauna of Macaronesian islands and nearby continental coasts: over fifty candidate endemic species

Oceanic islands are recognized evolutionary hotspots for terrestrial organisms, but little is known about their impact on marine organisms evolution and biogeography. The volcanic archipelagos of Macaronesia occupy a vast and complex region which is particularly suitable to investigate marine island biogeography. In this study, we used mitochondrial DNA sequences to investigate the genetic diferentiation between the populations from Webbnesia (i.e. Madeira, Selvagens and Canaries) and adjacent coasts, of 23 intertidal peracarid species. All species had unexpectedly high intraspecific genetic distances, reaching more than 20% in some cases. Between 79 and 95 Molecular Operational Taxonomic Units (MOTUs) were found in these species. Webbnesia populations displayed an impressive genetic diversity and high endemicity, with 83% of the MOTUs being private to these islands, particularly La Palma and Madeira. Network analyses suggested higher similarity between Webbnesia and Azores than with adjacent continental coasts. These results reveal an unanticipated and sweeping biogeographic discontinuity of peracaridean fauna between Webbnesia and the Iberian Peninsula, raising suspicion about the possible occurrence of identical patterns in other groups of marine invertebrates in the region. We emphasize the unique genetic heritage hosted by these islands, underlining the need to consider the fine scale endemicity in marine conservation efforts.

ecology↗

bioRxiv2020

A rapid urban biodiversity blitz using aquatic environmental DNA

Background As global biodiversity declines, there’s an increasing need to create an educated and engaged society. Having people from all ages participate in measuring biodiversity where they live helps to create awareness. Recently, the use of environmental DNA (eDNA) for biodiversity surveys has gained momentum. Here, we test whether sampling eDNA and metabarcoding can be used for rapid urban biodiversity surveys for educational purposes.Materials & Methods We sampled 2×1 L of water from each of 15 locations in the city of Trondheim, Norway, including a variety of freshwater, marine and brackish habitats. DNA was extracted, amplified in triplicate for the COI gene and sequenced. The obtained data were analysed on the novel mBRAVE platform, an online open access software and computing resource.Results The water samples were collected in two days by two people and the lab analysis was completed in five days by one person. Overall, we detected the presence of 501 taxa identified as belonging to 435 species, representing 90 orders and 18 phyla. On average, only 5.4% of the taxa were shared among six replicates per site. Based on the observed diversity, three distinct clusters were detected and related to geographic distribution of sites. There were some taxa shared between the habitats, with a substantial presence of terrestrial biota.Discussion Our results match expected patterns of biodiversity in the landscape and show that with minimal sampling effort, hundreds of species can be detected. Thus, using eDNA analysis of water is promising for rapid biodiversity surveys, and it is likely that more detailed results could be obtained by optimising field and lab methods for particular groups of interest. We recommend that rapid eDNA surveys, with openly available services and softwares, can be used to raise awareness in the importance of biodiversity.Competing Interest StatementThe authors have declared no competing interest.View Full Text

scientific communication and education↗

bioRxiv2019

Horizontal transfer and gene loss shaped the evolution of alpha-amylases in bilaterians

The subfamily GH13_1 of alpha-amylases is typical of Fungi, but it is also found in some unicellular eukaryotes (e.g. Amoebozoa, choanoflagellates) and non-bilaterian Metazoa. Since a previous study in 2007, GH13_1 amylases were considered ancestral to the Unikonts, including animals, except Bilateria, such that it was thought to have been lost in the ancestor of this clade. The only alpha-amylases known to be present in Bilateria so far belong to the GH13_15 and 24 subfamilies (commonly called bilaterian alpha-amylases) and were likely acquired by horizontal transfer from a proteobacterium. The taxonomic scope of Eukaryota genomes in databases has been greatly increased ever since 2007. We have surveyed GH13_1 sequences in recent data from ca. 1600 bilaterian species, 60 non-bilaterian animals and also in unicellular eukaryotes. As expected, we found a number of those sequences in non-bilaterians: Anthozoa (Cnidaria) and in sponges, confirming the previous observations, but none in jellyfishes and in Ctenophora. Our main and unexpected finding is that such fungal (also called Dictyo-type) amylases were also consistently retrieved in several bilaterian phyla: hemichordates (deuterostomes), brachiopods and related phyla, some molluscs and some annelids (protostomes). We discuss evolutionary hypotheses possibly explaining the scattered distribution of GH13_1 across bilaterians, namely, the retention of the ancestral gene in those phyla only and/or horizontal transfers from non-bilaterian donors.

evolutionary biology↗