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2,633 result(s) for "spike mutations"
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Genomic Surveillance of SARS-CoV-2 in the Southern Province of Zambia: Detection and Characterization of Alpha, Beta, Delta, and Omicron Variants of Concern
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) have significantly impacted the global epidemiology of the pandemic. From December 2020 to April 2022, we conducted genomic surveillance of SARS-CoV-2 in the Southern Province of Zambia, a region that shares international borders with Botswana, Namibia, and Zimbabwe and is a major tourist destination. Genetic analysis of 40 SARS-CoV-2 whole genomes revealed the circulation of Alpha (B.1.1.7), Beta (B.1.351), Delta (AY.116), and multiple Omicron subvariants with the BA.1 subvariant being predominant. Whereas Beta, Delta, and Omicron variants were associated with the second, third, and fourth pandemic waves, respectively, the Alpha variant was not associated with any wave in the country. Phylogenetic analysis showed evidence of local transmission and possible multiple introductions of SARS-CoV-2 VOCs in Zambia from different European and African countries. Across the 40 genomes analysed, a total of 292 mutations were observed, including 182 missense mutations, 66 synonymous mutations, 23 deletions, 9 insertions, 1 stop codon, and 11 mutations in the non-coding region. This study stresses the need for the continued monitoring of SARS-CoV-2 circulation in Zambia, particularly in strategically positioned regions such as the Southern Province which could be at increased risk of introduction of novel VOCs.
Attenuated SARS-CoV-2 variants with deletions at the S1/S2 junction
The emergence of SARS-CoV-2 has led to the current global coronavirus pandemic and more than one million infections since December 2019. The exact origin of SARS-CoV-2 remains elusive, but the presence of a distinct motif in the S1/S2 junction region suggests the possible acquisition of cleavage site(s) in the spike protein that promoted cross-species transmission. Through plaque purification of Vero-E6 cultured SARS-CoV-2, we found a series of variants which contain 15-30-bp deletions (Del-mut) or point mutations respectively at the S1/S2 junction. Examination of the original clinical specimen from which the isolate was derived, and 26 additional SARS-CoV-2 positive clinical specimens, failed to detect these variants. Infection of hamsters shows that one of the variants (Del-mut-1) which carries deletion of 10 amino acids (30bp) does not cause the body weight loss or more severe pathological changes in the lungs that is associated with wild type virus infection. We suggest that the unique cleavage motif promoting SARS-CoV-2 infection in humans may be under strong selective pressure, given that replication in permissive Vero-E6 cells leads to the loss of this adaptive function. It would be important to screen the prevalence of these variants in asymptomatic infected cases. The potential of the Del-mut variants as an attenuated vaccine or laboratory tool should be evaluated.
Inactivation of Pseudovirus Expressing the D614G Spike Protein Mutation using Nitric Oxide‐Plasma Activated Water
Variants of concern (VOCs) of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) exhibit high infectivity due to mutations, particularly in the spike protein, that facilitate enhanced binding of virus to human angiotensin‐converting enzyme 2 (hACE2). The D614G mutation, situated in S1‐domain, promotes the open conformation of spike protein, augmenting its interaction with hACE2. Activated water neutralizes pathogens by damaging biological molecules; however, its effect on mutated SARS‐CoV‐2 or VOCs requires further exploration. Here, the efficacy of nitric oxide (NOx)‐plasma activated water (PAW) in inhibiting infections by SARS‐CoV‐2 pseudovirus expressing D614G‐mutated spike protein is investigated, which serves as a model for mutated SARS‐CoV‐2. Results demonstrated high prevalence of D614G mutation in SARS‐CoV‐2 and its VOCs. NOx‐PAW is non‐toxic to cells at high concentration, inhibiting infection by 71%. Moreover, NOx‐PAW induced structural changes in S1‐domain of spike protein, reducing its binding affinity and lowering clathrin‐mediated endocytosis‐related gene expression. Additionally, in silico analysis revealed NOx species in NOx‐PAW played key role in impairing S1‐domain function of the mutated SARS‐CoV‐2 pseudovirus by interacting directly with it. Collectively, these findings reveal the potent inactivation ability of PAW against mutated SARS‐CoV‐2 and suggest its potential application in combating emerging variants of SARS‐CoV‐2 and other viral threats. SARS‐CoV‐2 mutants are of concern. The inactivation of mutated viruses by plasma‐activated water remains unclear. In this study, NOx‐PAW demonstrates inactivation of SARS‐CoV‐2 pseudovirus with D614G mutation by interacting with the amino acids in S1‐domain of mutated spike protein. Furthermore, RNS destabilizes S1‐domain leading to loss of bio‐functionality. This hinders the entry of viruses in host cells through CME pathway.
SARS-CoV-2 journey: from alpha variant to omicron and its sub-variants
The COVID-19 pandemic has affected hundreds of millions of individuals and caused more than six million deaths. The prolonged pandemic duration and the continual inter-individual transmissibility have contributed to the emergence of a wide variety of SARS-CoV-2 variants. Genomic surveillance and phylogenetic studies have shown that substantial mutations in crucial supersites of spike glycoprotein modulate the binding affinity of the evolved SARS-COV-2 lineages to ACE2 receptors and modify the binding of spike protein with neutralizing antibodies. The immunological spike mutations have been associated with differential transmissibility, infectivity, and therapeutic efficacy of the vaccines and the immunological therapies among the new variants. This review highlights the diverse genetic mutations assimilated in various SARS-CoV-2 variants. The implications of the acquired mutations related to viral transmission, infectivity, and COVID-19 severity are discussed. This review also addresses the effectiveness of human neutralizing antibodies induced by SARS-CoV-2 infection or immunization and the therapeutic antibodies against the ascended variants.
SARS-CoV-2 spike mutations alter structure and energetics to modulate ACE2 binding immune evasion and viral adaptation
The persistent evolution of SARS-CoV-2 is driven by mutations in the spike protein that modulate receptor binding, immune evasion, and structural stability. In this study, we deciphered the complex host-virus protein-protein interactions using an integrated molecular dynamics (MD) approach to assess the biophysical impacts of key spike mutations, including T478K, T478A, T478E, E484K, G496S, F490S, Q493E, and Y369C. Our findings reveal that viral adaptation hinges on trade-offs between transmissibility and immune escape. For instance, T478K enhances ACE2 binding through structural rigidification and salt bridge formation (e.g., K478-D30), favoring Omicron’s increased transmissibility. In contrast, T478A introduces polarity loss and interface relaxation, while T478E leads to electrostatic repulsion and weakened binding, both of which compromise interface stability. E484K balances antibody evasion (e.g., against LY-CoV555) with receptor stabilization via compensatory interactions (e.g., K484-D38). In vivo studies support these findings, showing that T478K and E484K enhance viral fitness and immune evasion in animal models. Mutations like G496S and F490S act as stealth adaptations, subtly destabilizing ACE2 or introducing metastability without fully disrupting binding. The high-risk Y369C mutation collapses the N-terminal domain supersite, enhancing immune evasion but requiring compensatory mutations (e.g., G142D) to maintain viability. Evolutionary strategies favor co-mutations (e.g., T478K + Q498R) that distribute fitness costs across residues. Notably, functionally conserved energetic hotspots such as T430, L390, V382, K386, F486, Q493 (RBD), and Q102, R192 (ACE2) consistently contributed to ACE2 engagement across all variants, representing potential targets for broad-spectrum therapeutics. Our work provides the importance of real-time surveillance for mutations that exploit conformational flexibility or compensatory networks, informing the design of durable vaccines and multi-specific antibodies. These insights bridge molecular mechanisms with evolutionary dynamics, offering a framework to anticipate and counter emerging variants.
Structural Evaluation of the Spike Glycoprotein Variants on SARS-CoV-2 Transmission and Immune Evasion
The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presents significant social, economic and political challenges worldwide. SARS-CoV-2 has caused over 3.5 million deaths since late 2019. Mutations in the spike (S) glycoprotein are of particular concern because it harbours the domain which recognises the angiotensin-converting enzyme 2 (ACE2) receptor and is the target for neutralising antibodies. Mutations in the S protein may induce alterations in the surface spike structures, changing the conformational B-cell epitopes and leading to a potential reduction in vaccine efficacy. Here, we summarise how the more important variants of SARS-CoV-2, which include cluster 5, lineages B.1.1.7 (Alpha variant), B.1.351 (Beta), P.1 (B.1.1.28/Gamma), B.1.427/B.1.429 (Epsilon), B.1.526 (Iota) and B.1.617.2 (Delta) confer mutations in their respective spike proteins which enhance viral fitness by improving binding affinity to the ACE2 receptor and lead to an increase in infectivity and transmission. We further discuss how these spike protein mutations provide resistance against immune responses, either acquired naturally or induced by vaccination. This information will be valuable in guiding the development of vaccines and other therapeutics for protection against the ongoing coronavirus disease 2019 (COVID-19) pandemic.
SARS-CoV-2 variants and effectiveness of vaccines: a review of current evidence
The SARS-CoV-2 virus is rapidly evolving via mutagenesis, lengthening the pandemic, and threatening the public health. Until August 2021, 12 variants of SARS-CoV-2 named as variants of concern (VOC; Alpha to Delta) or variants of interest (VOI; Epsilon to Mu), with significant impact on transmissibility, morbidity, possible reinfection and mortality, have been identified. The VOC Delta (B.1.617.2) of Indian origin is now the dominant and the most contagious variant worldwide as it provokes a strong binding to the human ACE2 receptor, increases transmissibility and manifests considerable immune escape strategies after natural infection or vaccination. Although the development and administration of SARS-CoV-2 vaccines, based on different technologies (mRNA, adenovirus carrier, recombinant protein, etc.), are very promising for the control of the pandemic, their effectiveness and neutralizing activity against VOCs varies significantly. In this review, we describe the most significant circulating variants of SARS-CoV-2, and the known effectiveness of currently available vaccines against them.
SARS-CoV-2 variants - Evolution, spike protein, and vaccines
Despite the rising natural and vaccines mediated immunity, several countries have experienced a resurgence of the Coronavirus disease of 2019 (COVID-19) due to the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. From Alpha to Omicron, the variants of concern (VOC) have evolved several spike protein mutations that may have an impact on virus characteristics, such as transmissibility and antigenicity. In this review, we describe the evolution of SARS-CoV-2, summarize current knowledge of epidemiological and clinical features of the variants, and discuss the response strategies in terms of vaccines to reduce the burden of COVID-19.
The emerging SARS-CoV-2 variants of concern
Since emerging from Wuhan, China, in December of 2019, the coronavirus (SARS-CoV-2) has been causing devastating severe respiratory infections in humans worldwide. With the disease spreading faster than the medical community could contain it, death tolls increased at an alarming rate worldwide, causing the World Health Organization to officially sanction the SARS-CoV-2 outbreak as a pandemic, leading to a state of worldwide lockdown for the majority of the year 2020. There have been reports of new strains of the virus emerging in various parts of the world, with some strains displaying even greater infectivity and transmissibility. Areas of the emerging variant of concern arise from countries like the United Kingdom, South Africa, Brazil, and India. These mutations carry a lineage from N501Y, D614G, N439K, Y453F, and others, which are globally dominated by clades 20A, 20B, and 20C. This literature review intends to identify and report SARS-CoV-2 variants that are currently evolving and their disease implications.
Using In Silico Bioinformatics Algorithms for the Accurate Prediction of the Impact of Spike Protein Mutations on the Pathogenicity, Stability, and Functionality of the SARS-CoV-2 Virus and Analysis of Potential Therapeutic Targets
Coronavirus disease 2019 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We have used bioinformatics to investigate seventeen mutations in the spike protein of SARS-CoV-2, as this mediates infection of human cells and is the target of most vaccine strategies and antibody-based therapies. Two mutations, H146Y and S221W, were identified as being most pathogenic. Mutations at positions D614G, A829T, and P1263L might also have deleterious effects on protein function. We hypothesized that candidate small molecules may be repurposed to combat viral infection. We investigated changes in binding energies of the ligands and the mutant proteins by assessing molecular docking. For an understanding of cellular function and organization, protein–protein interactions are also critical. Protein–protein docking for naïve and mutated structures of SARS-CoV-2 S protein was evaluated for their binding energy with the angiotensin-converting enzyme 2 (ACE2). These interactions might limit the binding of the SARS-CoV-2 spike protein to the ACE2 receptor or may have a deleterious effect on protein function that may limit infection. These results may have important implications for the transmission of SARS-CoV-2, its pathogenesis, and the potential for drug repurposing and immune therapies.