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1.
J Med Virol ; 92(6): 584-588, 2020 06.
Article in English | MEDLINE | ID: covidwho-685102

ABSTRACT

Last December 2019, a new virus, named novel Coronavirus (COVID-2019) causing many cases of severe pneumonia was reported in Wuhan, China. The virus knowledge is limited and especially about COVID-2019 pathogenesis. The Open Reading Frame 1ab (ORF1ab) of COVID-2019 has been analyzed to evidence the presence of mutation caused by selective pressure on the virus. For selective pressure analysis fast-unconstrained Bayesian approximation (FUBAR) was used. Homology modelling has been performed by SwissModel and HHPred servers. The presence of transmembrane helical segments in Coronavirus ORF1ab non structural protein 2 (nsp2) and nsp3 was tested by TMHMM, MEMSAT, and MEMPACK tools. Three-dimensional structures have been analyzed and displayed using PyMOL. FUBAR analysis revealed the presence of potential sites under positive selective pressure (P < .05). Position 723 in the COVID-2019 has a serine instead a glycine residue, while at aminoacidic position 1010 a proline instead an isoleucine. Significant (P < .05) pervasive negative selection in 2416 sites (55%) was found. The positive selective pressure could account for some clinical features of this virus compared with severe acute respiratory syndrome (SARS) and Bat SARS-like CoV. The stabilizing mutation falling in the endosome-associated-protein-like domain of the nsp2 protein could account for COVID-2019 high ability of contagious, while the destabilizing mutation in nsp3 proteins could suggest a potential mechanism differentiating COVID-2019 from SARS. These data could be helpful for further investigation aimed to identify potential therapeutic targets or vaccine strategy, especially in the actual moment when the epidemic is ongoing and the scientific community is trying to enrich knowledge about this new viral pathogen.


Subject(s)
Betacoronavirus/genetics , SARS Virus/genetics , Viral Nonstructural Proteins/chemistry , Viral Proteins/chemistry , Betacoronavirus/pathogenicity , Coronavirus Infections/virology , Female , Gene Expression , Humans , Male , Models, Molecular , Mutation , Pandemics , Pneumonia, Viral/virology , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , SARS Virus/pathogenicity , Selection, Genetic , Structural Homology, Protein , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism , Viral Proteins/genetics , Viral Proteins/metabolism
2.
J Med Virol ; 2020 Jun 03.
Article in English | MEDLINE | ID: covidwho-505875

ABSTRACT

Italy is the first western country suffering heavy severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission and disease impact after coronavirus disease-2019 pandemia started in China. Even though the presence of mutations on spike glycoprotein and nucleocapsid in Italian isolates has been reported, the potential impact of these mutations on viral transmission has not been evaluated. We have compared SARS-CoV-2 genome sequences from Italian patients with virus sequences from Chinese patients. We focussed upon three nonsynonymous mutations of genes coding for S(one) and N (two) viral proteins present in Italian isolates and absent in Chinese ones, using various bioinformatics tools. Amino acid analysis and changes in three-dimensional protein structure suggests the mutations reduce protein stability and, particularly for S1 mutation, the enhanced torsional ability of the molecule could favor virus binding to cell receptor(s). This theoretical interpretation awaits experimental and clinical confirmation.

3.
Biomed Res Int ; 2020: 4389089, 2020.
Article in English | MEDLINE | ID: covidwho-618728

ABSTRACT

The Coronavirus Disease 2019 (COVID-19) is a new viral infection caused by the severe acute respiratory coronavirus 2 (SARS-CoV-2). Genomic analyses have revealed that SARS-CoV-2 is related to Pangolin and Bat coronaviruses. In this report, a structural comparison between the Sars-CoV-2 Envelope and Membrane proteins from different human isolates with homologous proteins from closely related viruses is described. The analyses here reported show the high structural similarity of Envelope and Membrane proteins to the counterparts from Pangolin and Bat coronavirus isolates. However, the comparisons have also highlighted structural differences specific of Sars-CoV-2 proteins which may be correlated to the cross-species transmission and/or to the properties of the virus. Structural modelling has been applied to map the variant sites onto the predicted three-dimensional structure of the Envelope and Membrane proteins.


Subject(s)
Betacoronavirus/chemistry , Coronavirus Infections/virology , Pneumonia, Viral/virology , Viral Envelope Proteins/chemistry , Viral Matrix Proteins/chemistry , Alphacoronavirus/chemistry , Alphacoronavirus/classification , Alphacoronavirus/genetics , Amino Acid Sequence , Animals , Betacoronavirus/classification , Betacoronavirus/genetics , Chiroptera/virology , Coronaviridae/chemistry , Coronaviridae/classification , Coronaviridae/genetics , Eutheria/virology , Humans , Models, Molecular , Pandemics , Protein Conformation , Sequence Homology, Amino Acid , Species Specificity , Structural Homology, Protein , Viral Envelope Proteins/genetics , Viral Matrix Proteins/genetics
4.
Turk. J. Biol. ; Special issue 1(44): 178-184, 2020.
Article in English | ELSEVIER | ID: covidwho-619077

ABSTRACT

A previously unknown coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been shown to cause coronavirus disease 2019 (COVID-19) pandemic. The first case of COVID-19 in Turkey has been declared in March 11th, 2020 and from there on, more than 150,000 people in the country have been diagnosed with the disease. In this study, 62 viral sequences from Turkey, which have been uploaded to GISAID database, were analyzed by means of their nucleotide substitutions in comparison to the reference SARS-CoV-2 genome from Wuhan. Our results indicate that the viral isolates from Turkey harbor some common mutations with the viral strains from Europe, Oceania, North America and Asia. When the mutations were evaluated, C3037T, C14408T and A23403G were found to be the most common nucleotide substitutions among the viral isolates in Turkey, which are mostly seen as linked mutations and are part of a haplotype observed high in Europe.

5.
J Infect ; 81(1): e24-e27, 2020 07.
Article in English | MEDLINE | ID: covidwho-47836

ABSTRACT

BACKGROUND: SARS-CoV-2 is a new coronavirus that has spread globally, infecting more than 150000 people, and being declared pandemic by the WHO. We provide here bio-informatic, evolutionary analysis of 351 available sequences of its genome with the aim of mapping genome structural variations and the patterns of selection. METHODS: A Maximum likelihood tree has been built and selective pressure has been investigated in order to find any mutation developed during the SARS-CoV-2 epidemic that could potentially affect clinical evolution of the infection. FINDING: We have found in more recent isolates the presence of two mutations affecting the Non-Structural Protein 6 (NSP6) and the Open Reding Frame10 (ORF 10) adjacent regions. Amino acidic change stability analysis suggests both mutations could confer lower stability of the protein structures. INTERPRETATION: One of the two mutations, likely developed within the genome during virus spread, could affect virus intracellular survival. Genome follow-up of SARS-CoV-2 spread is urgently needed in order to identify mutations that could significantly modify virus pathogenicity.


Subject(s)
Betacoronavirus/genetics , Capsid Proteins/genetics , Coronavirus Infections/virology , Mutation , Pneumonia, Viral/virology , Autophagy , Evolution, Molecular , Gene Expression Regulation, Viral , Genome, Viral , Humans , Likelihood Functions , Models, Molecular , Open Reading Frames , Pandemics , Protein Conformation
7.
Chemotherapy ; : 1-9, 2020 Apr 07.
Article in English | MEDLINE | ID: covidwho-38684

ABSTRACT

BACKGROUND: In late December 2019, Chinese health authorities reported an outbreak of pneumonia of unknown origin in Wuhan, Hubei Province. SUMMARY: A few days later, the genome of a novel coronavirus was released (http://viro-logical.org/t/novel-2019-coronavirus-genome/319; Wuhan-Hu-1, GenBank accession No. MN908947) and made publicly available to the scientific community. This novel coronavirus was provisionally named 2019-nCoV, now SARS-CoV-2 according to the Coronavirus Study Group of the International Committee on Taxonomy of Viruses. SARS-CoV-2 belongs to the Coronaviridae family, Betacoronavirus genus, subgenus Sarbecovirus. Since its discovery, the virus has spread globally, causing thousands of deaths and having an enormous impact on our health systems and economies. In this review, we summarize the current knowledge about the epidemiology, phylogenesis, homology modeling, and molecular diagnostics of SARS-CoV-2. Key Messages: Phylogenetic analysis is essential to understand viral evolution, whereas homology modeling is important for vaccine strategies and therapies. Highly sensitive and specific diagnostic assays are key to case identification, contact tracing, identification of the animal source, and implementation of control measures.

9.
J Med Virol ; 2020 Mar 19.
Article in English | MEDLINE | ID: covidwho-10309

ABSTRACT

The emergence of the novel betacoronavirus, recently renamed as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has raised serious concerns due to the virus's rapid dissemination worldwide. Nevertheless, there is limited information about the genomic epidemiology of SARS-CoV-2 circulating in Italy from surveillance studies. The shortage of complete genomic sequences available impairs our understanding of the SARS-CoV-2 introduction and establishment in the country. To better understand its dynamics in Italy, we analyzed complete genomes of SARS-CoV-2 isolates, obtained directly from clinical samples. Our phylogenetic reconstructions suggest possible multiple introduction of SARS-CoV-2. Continued genomic surveillance strategies are needed to improve monitoring and understanding of the current SARS-CoV-2 epidemics, which might help to attenuate public health impact of infectious diseases.

10.
Data Brief ; (29)20200401.
Article in English | ELSEVIER | ID: covidwho-2363

ABSTRACT

Coronavirus disease 2019 (COVID-2019) has been recognized as a global threat, and several studies are being conducted using various mathematical models to predict the probable evolution of this epidemic. These mathematical models based on various factors and analyses are subject to potential bias. Here, we propose a simple econometric model that could be useful to predict the spread of COVID-2019. We performed Auto Regressive Integrated Moving Average (ARIMA) model prediction on the Johns Hopkins epidemiological data to predict the epidemiological trend of the prevalence and incidence of COVID-2019. For further comparison or for future perspective, case definition and data collection have to be maintained in real time.

11.
J Med Virol ; 92(4): 455-459, 2020 04.
Article in English | MEDLINE | ID: covidwho-2364

ABSTRACT

There is a worldwide concern about the new coronavirus 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 sequences of 2019-nCoV, 12 whole genome sequences of 2019-nCoV, and 12 highly similar whole genome sequences available in gene bank (five from the severe acute respiratory syndrome, two from Middle East respiratory syndrome, and five from bat SARS-like coronavirus). Fast unconstrained Bayesian approximation analysis shows that the nucleocapsid and the spike glycoprotein have some sites under positive pressure, whereas homology modeling revealed 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 Spike Glycoprotein and nucleocapsid protein. From these results, the new 2019-nCoV is distinct from SARS virus, probably trasmitted from bats after mutation conferring ability to infect humans.


Subject(s)
Chiroptera , Coronavirus Infections , Coronavirus , SARS Virus , Animals , Bayes Theorem , Betacoronavirus , Evolution, Molecular , Humans , Phylogeny , Spike Glycoprotein, Coronavirus/genetics
12.
J Med Virol ; 92(4): 455-459, 2020 04.
Article in English | MEDLINE | ID: covidwho-1331

ABSTRACT

There is a worldwide concern about the new coronavirus 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 sequences of 2019-nCoV, 12 whole genome sequences of 2019-nCoV, and 12 highly similar whole genome sequences available in gene bank (five from the severe acute respiratory syndrome, two from Middle East respiratory syndrome, and five from bat SARS-like coronavirus). Fast unconstrained Bayesian approximation analysis shows that the nucleocapsid and the spike glycoprotein have some sites under positive pressure, whereas homology modeling revealed 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 Spike Glycoprotein and nucleocapsid protein. From these results, the new 2019-nCoV is distinct from SARS virus, probably trasmitted from bats after mutation conferring ability to infect humans.


Subject(s)
Chiroptera , Coronavirus Infections , Coronavirus , SARS Virus , Animals , Bayes Theorem , Betacoronavirus , Evolution, Molecular , Humans , Phylogeny , Spike Glycoprotein, Coronavirus/genetics
13.
Pathog Glob Health ; 114(2): 64-67, 2020 03.
Article in English | MEDLINE | ID: covidwho-795

ABSTRACT

The global spread of the 2019-nCoV is continuing and is fast moving, as indicated by the WHO raising the risk assessment to high. In this article, we provide a preliminary phylodynamic and phylogeographic analysis of this new virus. A Maximum Clade Credibility tree has been built using the 29 available whole genome sequences of 2019-nCoV and two whole genome sequences that are highly similar sequences from Bat SARS-like Coronavirus available in GeneBank. We are able to clarify the mechanism of transmission among the countries which have provided the 2019-nCoV sequence isolates from their patients. The Bayesian phylogeographic reconstruction shows that the 2019-2020 nCoV most probably originated from the Bat SARS-like Coronavirus circulating in the Rhinolophus bat family. In agreement with epidemiological observations, the most likely geographic origin of the new outbreak was the city of Wuhan, China, where 2019-nCoV time of the most recent common ancestor emerged, according to molecular clock analysis, around November 25th, 2019. These results, together with previously recorded epidemics, suggest a recurring pattern of periodical epizootic outbreaks due to Betacoronavirus. Moreover, our study describes the same population genetic dynamic underlying the SARS 2003 epidemic, and suggests the urgent need for the development of effective molecular surveillance strategies of Betacoronavirus among animals and Rhinolophus of the bat family.


Subject(s)
Betacoronavirus/genetics , Chiroptera/virology , Coronavirus Infections/genetics , Coronavirus/genetics , Evolution, Molecular , Genome, Viral , Phylogeny , Pneumonia, Viral/genetics , Animals , Bayes Theorem , China/epidemiology , Coronavirus/isolation & purification , Coronavirus Infections/epidemiology , Coronavirus Infections/virology , DNA, Viral/genetics , Disease Outbreaks , Disease Reservoirs/virology , Global Health , Humans , Pandemics , Pneumonia, Viral/epidemiology , Pneumonia, Viral/virology , Sequence Analysis, Protein , Zoonoses/epidemiology , Zoonoses/genetics
14.
J Med Virol ; 92(5): 518-521, 2020 05.
Article in English | MEDLINE | ID: covidwho-321

ABSTRACT

A novel Coronavirus, 2019-nCoV, has been identified as the causal pathogen of an ongoing epidemic, with the first cases reported in Wuhan, China, last December 2019, and has since spread to other countries worldwide, included Europe and very recently Italy. In this short report, phylogenetic reconstruction was used to better understand the transmission dynamics of the virus from its first introduction in China focusing on the more recent evidence of infection in a couple of Chinese tourists arrived in Italy on 23rd January 2020 and labeled as Coronavirus Italian cases. A maximum clade credibility tree has been built using a dataset of 54 genome sequences of 2019-nCoV plus two closely related bat strains (SARS-like CoV) available in GenBank. Bayesian time-scaled phylogenetic analysis was implemented in BEAST 1.10.4. The Bayesian phylogenetic reconstruction showed that 2019-2020 nCoV firstly introduced in Wuhan on 25 November 2019, started epidemic transmission reaching many countries worldwide, including Europe and Italy where the two strains isolated dated back 19 January 2020, the same that the Chinese tourists arrived in Italy. Strains isolated outside China were intermixed with strains isolated in China as evidence of likely imported cases in Rome, Italy, and Europe, as well. In conclusion, this report suggests that further spread of 2019-nCoV epidemic was supported by human mobility and that quarantine of suspected or diagnosed cases is useful to prevent further transmission. Viral genome phylogenetic analysis represents a useful tool for the evaluation of transmission dynamics and preventive action.


Subject(s)
Betacoronavirus/genetics , Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Genome, Viral , Pneumonia, Viral/epidemiology , Pneumonia, Viral/transmission , Animals , Betacoronavirus/isolation & purification , Chiroptera/virology , Humans , Interatrial Block , Italy/epidemiology , Models, Genetic , Mutation Rate , Pandemics , Phylogeny
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