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Benvenuto, D.

Publications and source records attributed to Benvenuto, D..

5 recordsLinked to original sources

Genome-based comparison between the recombinant SARS-CoV-2 XBB and its parental lineages

Recombination is the main contributor to RNA virus evolution, and SARS-CoV-2 during the pandemic produced several recombinants. The most recent SARS-CoV-2 recombinant is the lineage labeled XBB, also known as Gryphon, which arose from BJ.1 and BM. 1.1.1. Here we performed a genome-based survey aimed to compare the new recombinant with its parental lineages that never became dominant. Genetic analyses indicated that the recombinant XBB and its first descendant XBB.1 show an evolutionary condition typical of an evolutionary blind background with no further epidemiologically relevant descendant. Genetic variability and expansion capabilities are slightly higher than parental lineages. Bayesian Skyline Plot indicates that XBB reached its plateau around October 6, 2022 and after an initial rapid growth the viral population size did not further expand, and around November 10, 2022 its levels of genetic variability decreased. Simultaneously with the reduction of the XBB population size, an increase of the genetic variability of its first sub-lineage XBB.1 occurred, that in turn reached the plateau around November 9, 2022 showing a kind of vicariance with its direct progenitors. Structure analysis indicates that the affinity for ACE2 surface in XBB/XBB.1 RBDs is weaker than for BA.2 RBD. In conclusion, nowadays XBB and XBB.1 do not show evidence about a particular danger or high expansion capability. Genome-based monitoring must continue uninterrupted in order to individuate if further mutations can make XBB more dangerous or generate new subvariants with different expansion capability.

genetics↗

Genetic and structural data on the SARS-CoV-2 Omicron BQ.1 variant reveal its low potential for epidemiological expansion

The BQ.1 SARS-CoV-2 variant, also known as Cerberus, is one of the most recent Omicron descendant lineages. Compared to its direct progenitor BA.5, BQ.1 carries out some additional spike mutations in some key antigenic site which confer it further immune escape ability over other circulating lineage. In such a context, here we performed a genome-based survey aimed to obtain an as complete as possible nuance of this rapidly evolving Omicron subvariant. Genetic data suggests that BQ.1 represents an evolutionary blind background, lacking of the rapid diversification which is typical of a dangerous lineage. Indeed, the evolutionary rate of BQ.1 is very similar to that of BA.5 (7.6 x 10-4 and 7 x 10-4 subs/site/year, respectively), which is circulating by several months. Bayesian Skyline Plot reconstruction, indicates low level of genetic variability, suggesting that the peak has been reached around September 3, 2022. Structure analyses performed by comparing the properties of BQ.1 and BA.5 RBD indicated that the impact of the BQ.1 mutations on the affinity for ACE2 may be modest. Likewise, immunoinformatic analyses showed modest differences between the BQ.1 and the BA5 potential B-cells epitope. In conclusion, genetic and structural analysis on SARS-CoV-2 BQ.1 suggest that, it does not show evidence about its particular dangerous or high expansion capability. The monitoring genome-based must continue uninterrupted for a better understanding of its descendant and all other lineages.

molecular biology↗

The evolution of Monkeypox virus: a genetic and structural analysis reveals mutations in proteins involved in host-pathogen interaction

BackgroundOver the past few months, we have witnessed a new outbreak of a MPXV that has been detected without a clear link to Africa and has quickly spread globally. MethodsIn this article we investigate the mutational pattern of the MPXV and provide evidence for the presence of 6 new mutations that appear to characterize the current MPX-2022 outbreak. With the use of a number of chemical and physical parameters, we predict the stability of the mutated proteins, and propose an interpretation of the impact of these mutations on viral fitness). FindingsMost mutations, particularly the Immunomodulator A46, TNFr and Large transcript constituent, affect proteins playing an important role in host response to MPVX infection and could also be relevant to the clinical features of the 2022 MPXV outbreak. InterpretationAlthough further, experimental work is necessary for a full understanding of the impact of the mutations here reported on virus replication pathways and host immunomodulation, our in-silico data suggest the importance of monitoring the emergence of new MPXV mutations for the prevention of future outbreaks potentially dangerous for public health. FundingNo funding to declare

bioinformatics↗

Cutting epitopes to survive: the case of lambda variant

This manuscript concisely reports an in-silico study on the potential impact of the Spike protein mutations on immuno-escape ability of SARS-CoV-2 lambda variant. Biophysical and bioinformatics data suggest that a combination of shortening immunogenic epitope loops and generation of potential N-glycosylation sites may be a viable adaptation strategy potentially allowing this emerging viral variant escaping host immunity.

bioinformatics↗

The 2019-new Coronavirus epidemic: evidence for virus evolution

There is concern about a new coronavirus, the 2019-nCoV, as a global public health threat. In this article, we provide a preliminary evolutionary and molecular epidemiological analysis of this new virus. A phylogenetic tree has been built using the 15 available whole genome sequence of 2019-nCoV and 12 whole genome sequences highly similar sequences available in gene bank (5 from SARS, 2 from MERS and 5 from Bat SARS-like Coronavirus). FUBAR analysis shows that the Nucleocapsid and the Spike Glycoprotein has some sites under positive pressure while homology modelling helped to explain some molecular and structural differences between the viruses. The phylogenetic tree showed that 2019.nCoV significantly clustered with Bat SARS-like Coronavirus sequence isolated in 2015, whereas structural analysis revealed mutation in S and nucleocapsid proteins. From these results, 2019nCoV could be considered a coronavirus distinct from SARS virus, probably transmitted from bats or another host where mutations conferred upon it the ability to infect humans.

bioinformatics↗