Emerging mutations in spike and other structural proteins of SARS-CoV-2

The structural proteins, spike (S), nucleocapsid (N), membrane (M), and envelope (E), of severe acute respiratory syndrome (SARS-CoV-2) play a critical role from attachment to replication and virulency. Recently a bulk of genomes have been sequenced from different geographical regions with significant number of variations. Therefore, the current study was aimed to find variations in the structural proteins. This is the first comprehensive study in which we screened 2,95,000 complete genomes in global initiative on sharing all influenza data (GISAID), submitted from December 2019 to December 2020. We detected 4725 non-synonymous mutations in S, 627 in M, 259 in E, and 1631 mutations in N protein, among which the most frequently occurring mutations in S protein are D614G (n=2,66,513), A222V (n=59,697), L18F (n=28,015) and that of M protein are; T175M (n=1286), D3G (n=968), L17I (n=621), A2V (n=463), and A2S (n=460). The most commonly circulating variants in E includes, S68F (n=419), P71S (n=264), and L73F (n=218). Similarly, the N protein also harbored the most common variants which include; R203K (n=82,570), G204R (n=81,858), and A220V (n=39,729). The frequency of N501Y (n=4362) in S is determining a tight interaction of CoV-2 RBD with ACE2. These wide range of mutations in structural proteins may not only affect the therapeutic efforts but also the vaccines efficacy and diagnostics specificity. We suggest that geographically strain specific variations should be investigated for effective drugs, vaccine, and the antibodies combinations. Alternatively, immune boosting compounds might be very useful for successful eradication of CoV-2 infections.

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Structure-function investigation of a new VUI-202012/01 SARS-CoV-2 variant

10.1101/2021.01.01.425028 ◽

2021 ◽

Author(s):

Jasdeep Singh ◽

Nasreen Z. Ehtesham ◽

Syed Asad Rahman ◽

Seyed E. Hasnain

Keyword(s):

Central China ◽

Structural Proteins ◽

Structural Function ◽

Upper Respiratory Tract ◽

E Proteins ◽

Gene Target ◽

S Protein ◽

N Protein ◽

Synonymous Mutations ◽

South East England

AbstractThe SARS-CoV-2 (Severe Acute Respiratory Syndrome-Coronavirus) has accumulated multiple mutations during its global circulation. Recently, a new strain of SARS-CoV-2 (VUI 202012/01) had been identified leading to sudden spike in COVID-19 cases in South-East England. The strain has accumulated 23 mutations which have been linked to its immune evasion and higher transmission capabilities. Here, we have highlighted structural-function impact of crucial mutations occurring in spike (S), ORF8 and nucleocapsid (N) protein of SARS-CoV-2. Some of these mutations might confer higher fitness to SARS-CoV-2.SummarySince initial outbreak of COVID-19 in Wuhan city of central China, its causative agent; SARS-CoV-2 virus has claimed more than 1.7 million lives out of 77 million populations and still counting. As a result of global research efforts involving public-private-partnerships, more than 0.2 million complete genome sequences have been made available through Global Initiative on Sharing All Influenza Data (GISAID). Similar to previously characterized coronaviruses (CoVs), the positive-sense single-stranded RNA SARS-CoV-2 genome codes for ORF1ab non-structural proteins (nsp(s)) followed by ten or more structural/nsps [1, 2]. The structural proteins include crucial spike (S), nucleocapsid (N), membrane (M), and envelope (E) proteins. The S protein mediates initial contacts with human hosts while the E and M proteins function in viral assembly and budding. In recent reports on evolution of SARS-CoV-2, three lineage defining non-synonymous mutations; namely D614G in S protein (Clade G), G251V in ORF3a (Clade V) and L84S in ORF 8 (Clade S) were observed [2–4]. The latest pioneering works by Plante et al and Hou et al have shown that compared to ancestral strain, the ubiquitous D614G variant (clade G) of SARS-CoV-2 exhibits efficient replication in upper respiratory tract epithelial cells and transmission, thereby conferring higher fitness [5, 6]. As per latest WHO reports on COVID-19, a new strain referred as SARS-CoV-2 VUI 202012/01 (Variant Under Investigation, year 2020, month 12, variant 01) had been identified as a part of virological and epidemiological analysis, due to sudden rise in COVID-19 detected cases in South-East England [7]. Preliminary reports from UK suggested higher transmissibility (increase by 40-70%) of this strain, escalating Ro (basic reproduction number) of virus to 1.5-1.7 [7, 8]. This apparent fast spreading variant inculcates 23 mutations; 13 non-synonymous, 6 synonymous and 4 amino acid deletions [7]. In the current scenario, where immunization programs have already commenced in nations highly affected by COVID-19, advent of this new strain variant has raised concerns worldwide on its possible role in disease severity and antibody responses. The mutations also could also have significant impact on diagnostic assays owing to S gene target failures.

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Emerging Mutations in Nsp1 of SARS-CoV-2 and Their Effect on the Structural Stability

Pathogens ◽

10.3390/pathogens10101285 ◽

2021 ◽

Vol 10 (10) ◽

pp. 1285

Author(s):

Kejie Mou ◽

Farwa Mukhtar ◽

Muhammad Tahir Khan ◽

Doaa B. Darwish ◽

Shaoliang Peng ◽

...

Keyword(s):

Drug Targets ◽

Vaccine Development ◽

Innate Immune ◽

Coding Region ◽

Synonymous Mutations ◽

Wide Range ◽

Frequent Mutations ◽

Loop Regions ◽

Genome Accession ◽

Comprehensive Study

The genome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) encodes 16 non-structural (Nsp) and 4 structural proteins. Among the Nsps, Nsp1 inhibits host gene expression and also evades the immune system. This protein has been proposed as a target for vaccine development and also for drug design. Owing to its important role, the current study aimed to identify mutations in Nsp1 and their effect on protein stability and flexibility. This is the first comprehensive study in which 295,000 complete genomes have been screened for mutations after alignment with the Wuhan-Hu-1 reference genome (Accession NC_045512), using the CoVsurver app. The sequences harbored 933 mutations in the entire coding region of Nsp1. The most frequently occurring mutation in the 180-amino-acid Nsp1 protein was R24C (n = 1122), followed by D75E (n = 890), D48G (n = 881), H110Y (n = 860), and D144A (n = 648). Among the 933 non-synonymous mutations, 529 exhibited a destabilizing effect. Similarly, a gain in flexibility was observed in 542 mutations. The majority of the most frequent mutations were detected in the loop regions. These findings imply that Nsp1 mutations might be useful to exploit SARS-CoV-2′s pathogenicity. Genomic sequencing of SARS-CoV-2 on a regular basis will further assist in analyzing variations among the drug targets and to test the diagnostic accuracy. This wide range of mutations and their effect on Nsp1’s stability may have some consequences for the host’s innate immune response to SARS-CoV-2 infection and also for the vaccines’ efficacy. Based on this mutational information, geographically strain-specific drugs, vaccines, and antibody combinations could be a useful strategy against SARS-CoV-2 infection.

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Shooting a Tiger

10.1093/oso/9780199489381.001.0001 ◽

2018 ◽

Author(s):

Vijaya Ramadas Mandala

Keyword(s):

Critical Role ◽

Late Nineteenth Century ◽

Way Of Life ◽

Colonial India ◽

British Raj ◽

Early Colonial ◽

Wide Range ◽

Forest Legislation ◽

Imperial Governance ◽

North And South

The main contention of Shooting a Tiger is that hunting during the colonial period was not merely a recreational activity, but a practice intimately connected with imperial governance. The book positions shikar or hunting at the heart of colonial rule by demonstrating that, for the British in India, it served as a political, practical, and symbolic apparatus in the consolidation of power and rule during the nineteenth and early twentieth centuries. The book analyses early colonial hunting during the Company period, and then surveys different aspects of hunting during the high imperial decades in the later nineteenth and early twentieth centuries. The book draws upon an impressive array of archival material and uses a wide range of evidence to support its contentions. It examines hunting at a variety of social and ethnic levels—military, administrative, elite, princely India, Indian professional hunters, and in terms of Indian auxiliaries and (sometimes) resisters. It also deals with different geographical contexts—the plains, the mountains, north and south India. The exclusive privilege of hunting exercised by the ruling classes, following colonial forest legislation, continued to be extended to the Indian princes who played a critical role in sustaining the lavish hunts that became the hallmark of the late nineteenth-century British Raj. Hunting was also a way of life in colonial India, undertaken by officials and soldiers alike alongside their everyday duties, necessary for their mental sustenance and vital for the smooth operation of the colonial administration. There are also two final chapters on conservation, particularly the last chapter focusing on two British hunter-turned-conservationists, Jim Corbett and Colonel Richard Burton.

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Protease Inhibitors as Antiviral Agents

Clinical Microbiology Reviews ◽

10.1128/cmr.11.4.614 ◽

1998 ◽

Vol 11 (4) ◽

pp. 614-627 ◽

Cited By ~ 118

Author(s):

A. K. Patick ◽

K. E. Potts

Keyword(s):

Protease Inhibitors ◽

Viral Infections ◽

Critical Role ◽

Antiviral Agents ◽

Antiviral Agent ◽

Structural Proteins ◽

Viral Protease ◽

Virus Particles ◽

Viral Proteases ◽

Viral Polyprotein

SUMMARY Currently, there are a number of approved antiviral agents for use in the treatment of viral infections. However, many instances exist in which the use of a second antiviral agent would be beneficial because it would allow the option of either an alternative or a combination therapeutic approach. Accordingly, virus-encoded proteases have emerged as new targets for antiviral intervention. Molecular studies have indicated that viral proteases play a critical role in the life cycle of many viruses by effecting the cleavage of high-molecular-weight viral polyprotein precursors to yield functional products or by catalyzing the processing of the structural proteins necessary for assembly and morphogenesis of virus particles. This review summarizes some of the important general features of virus-encoded proteases and highlights new advances and/or specific challenges that are associated with the research and development of viral protease inhibitors. Specifically, the viral proteases encoded by the herpesvirus, retrovirus, hepatitis C virus, and human rhinovirus families are discussed.

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Structure and Function of Major SARS-CoV-2 and SARS-CoV Proteins

Bioinformatics and Biology Insights ◽

10.1177/11779322211025876 ◽

2021 ◽

Vol 15 ◽

pp. 117793222110258

Author(s):

Ritesh Gorkhali ◽

Prashanna Koirala ◽

Sadikshya Rijal ◽

Ashmita Mainali ◽

Adesh Baral ◽

...

Keyword(s):

Genomic Organization ◽

Membrane Vesicles ◽

Structural Proteins ◽

Host Immune System ◽

Accessory Proteins ◽

Nonstructural Proteins ◽

N Protein ◽

Small Proteins ◽

Methylation Mark ◽

And Function

SARS-CoV-2 virus, the causative agent of COVID-19 pandemic, has a genomic organization consisting of 16 nonstructural proteins (nsps), 4 structural proteins, and 9 accessory proteins. Relative of SARS-CoV-2, SARS-CoV, has genomic organization, which is very similar. In this article, the function and structure of the proteins of SARS-CoV-2 and SARS-CoV are described in great detail. The nsps are expressed as a single or two polyproteins, which are then cleaved into individual proteins using two proteases of the virus, a chymotrypsin-like protease and a papain-like protease. The released proteins serve as centers of virus replication and transcription. Some of these nsps modulate the host’s translation and immune systems, while others help the virus evade the host immune system. Some of the nsps help form replication-transcription complex at double-membrane vesicles. Others, including one RNA-dependent RNA polymerase and one exonuclease, help in the polymerization of newly synthesized RNA of the virus and help minimize the mutation rate by proofreading. After synthesis of the viral RNA, it gets capped. The capping consists of adding GMP and a methylation mark, called cap 0 and additionally adding a methyl group to the terminal ribose called cap1. Capping is accomplished with the help of a helicase, which also helps remove a phosphate, two methyltransferases, and a scaffolding factor. Among the structural proteins, S protein forms the receptor of the virus, which latches on the angiotensin-converting enzyme 2 receptor of the host and N protein binds and protects the genomic RNA of the virus. The accessory proteins found in these viruses are small proteins with immune modulatory roles. Besides functions of these proteins, solved X-ray and cryogenic electron microscopy structures related to the function of the proteins along with comparisons to other coronavirus homologs have been described in the article. Finally, the rate of mutation of SARS-CoV-2 residues of the proteome during the 2020 pandemic has been described. Some proteins are mutated more often than other proteins, but the significance of these mutation rates is not fully understood.

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Pseudomonas aeruginosa PA80 is a cystic fibrosis isolate deficient in RhlRI quorum sensing

Scientific Reports ◽

10.1038/s41598-021-85100-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Syed A. K. Shifat Ahmed ◽

Michelle Rudden ◽

Sabrina M. Elias ◽

Thomas J. Smyth ◽

Roger Marchant ◽

...

Keyword(s):

Cystic Fibrosis ◽

Pseudomonas Aeruginosa ◽

Quorum Sensing ◽

Virulence Factors ◽

Genomic Islands ◽

Clinical Strain ◽

Whole Genome ◽

Synonymous Mutations ◽

Wide Range

AbstractPseudomonas aeruginosa uses quorum sensing (QS) to modulate the expression of several virulence factors that enable it to establish severe infections. The QS system in P. aeruginosa is complex, intricate and is dominated by two main N-acyl-homoserine lactone circuits, LasRI and RhlRI. These two QS systems work in a hierarchical fashion with LasRI at the top, directly regulating RhlRI. Together these QS circuits regulate several virulence associated genes, metabolites, and enzymes in P. aeruginosa. Paradoxically, LasR mutants are frequently isolated from chronic P. aeruginosa infections, typically among cystic fibrosis (CF) patients. This suggests P. aeruginosa can undergo significant evolutionary pathoadaptation to persist in long term chronic infections. In contrast, mutations in the RhlRI system are less common. Here, we have isolated a clinical strain of P. aeruginosa from a CF patient that has deleted the transcriptional regulator RhlR entirely. Whole genome sequencing shows the rhlR locus is deleted in PA80 alongside a few non-synonymous mutations in virulence factors including protease lasA and rhamnolipid rhlA, rhlB, rhlC. Importantly we did not observe any mutations in the LasRI QS system. PA80 does not appear to have an accumulation of mutations typically associated with several hallmark pathoadaptive genes (i.e., mexT, mucA, algR, rpoN, exsS, ampR). Whole genome comparisons show that P. aeruginosa strain PA80 is closely related to the hypervirulent Liverpool epidemic strain (LES) LESB58. PA80 also contains several genomic islands (GI’s) encoding virulence and/or resistance determinants homologous to LESB58. To further understand the effect of these mutations in PA80 QS regulatory and virulence associated genes, we compared transcriptional expression of genes and phenotypic effects with isogenic mutants in the genetic reference strain PAO1. In PAO1, we show that deletion of rhlR has a much more significant impact on the expression of a wide range of virulence associated factors rather than deletion of lasR. In PA80, no QS regulatory genes were expressed, which we attribute to the inactivation of the RhlRI QS system by deletion of rhlR and mutation of rhlI. This study demonstrates that inactivation of the LasRI system does not impact RhlRI regulated virulence factors. PA80 has bypassed the common pathoadaptive mutations observed in LasR by targeting the RhlRI system. This suggests that RhlRI is a significant target for the long-term persistence of P. aeruginosa in chronic CF patients. This raises important questions in targeting QS systems for therapeutic interventions.

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Controlling Teleportation-Based Locomotion in Virtual Reality with Hand Gestures: A Comparative Evaluation of Two-Handed and One-Handed Techniques

Electronics ◽

10.3390/electronics10060715 ◽

2021 ◽

Vol 10 (6) ◽

pp. 715

Author(s):

Alexander Schäfer ◽

Gerd Reis ◽

Didier Stricker

Keyword(s):

Virtual Reality ◽

Virtual Worlds ◽

User Preferences ◽

Interaction Techniques ◽

Hand Gestures ◽

Wide Range ◽

Effectiveness And Efficiency ◽

High Degree ◽

Additional Hardware ◽

Comprehensive Study

Virtual Reality (VR) technology offers users the possibility to immerse and freely navigate through virtual worlds. An important component for achieving a high degree of immersion in VR is locomotion. Often discussed in the literature, a natural and effective way of controlling locomotion is still a general problem which needs to be solved. Recently, VR headset manufacturers have been integrating more sensors, allowing hand or eye tracking without any additional required equipment. This enables a wide range of application scenarios with natural freehand interaction techniques where no additional hardware is required. This paper focuses on techniques to control teleportation-based locomotion with hand gestures, where users are able to move around in VR using their hands only. With the help of a comprehensive study involving 21 participants, four different techniques are evaluated. The effectiveness and efficiency as well as user preferences of the presented techniques are determined. Two two-handed and two one-handed techniques are evaluated, revealing that it is possible to move comfortable and effectively through virtual worlds with a single hand only.

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Proteomic Analysis of Zeb1 Interactome in Breast Carcinoma Cells

Molecules ◽

10.3390/molecules26113143 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3143

Author(s):

Sergey E. Parfenyev ◽

Sergey V. Shabelnikov ◽

Danila Y. Pozdnyakov ◽

Olga O. Gnedina ◽

Leonid S. Adonin ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Epithelial To Mesenchymal Transition ◽

Critical Role ◽

Malignant Neoplasm ◽

Malignant Neoplasms ◽

Breast Cancer Patients ◽

Survival Prognosis ◽

Mesenchymal Transition ◽

Wide Range

Breast cancer is the most frequently diagnosed malignant neoplasm and the second leading cause of cancer death among women. Epithelial-to-mesenchymal Transition (EMT) plays a critical role in the organism development, providing cell migration and tissue formation. However, its erroneous activation in malignancies can serve as the basis for the dissemination of cancer cells and metastasis. The Zeb1 transcription factor, which regulates the EMT activation, has been shown to play an essential role in malignant transformation. This factor is involved in many signaling pathways that influence a wide range of cellular functions via interacting with many proteins that affect its transcriptional functions. Importantly, the interactome of Zeb1 depends on the cellular context. Here, using the inducible expression of Zeb1 in epithelial breast cancer cells, we identified a substantial list of novel potential Zeb1 interaction partners, including proteins involved in the formation of malignant neoplasms, such as ATP-dependent RNA helicase DDX17and a component of the NURD repressor complex, CTBP2. We confirmed the presence of the selected interactors by immunoblotting with specific antibodies. Further, we demonstrated that co-expression of Zeb1 and CTBP2 in breast cancer patients correlated with the poor survival prognosis, thus signifying the functionality of the Zeb1–CTBP2 interaction.

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Development of cancer metabolism as a therapeutic target: new pathways, patient studies, stratification and combination therapy

British Journal of Cancer ◽

10.1038/s41416-019-0666-4 ◽

2019 ◽

Vol 122 (1) ◽

pp. 1-3 ◽

Cited By ~ 4

Author(s):

Adrian L. Harris

Keyword(s):

Metabolic Pathways ◽

Trial Design ◽

Cancer Metabolism ◽

Aerobic Glycolysis ◽

Critical Role ◽

Therapeutic Approaches ◽

Preclinical Models ◽

Wide Range ◽

Patient Studies

AbstractCancer metabolism has undergone a resurgence in the last decade, 70 years after Warburg described aerobic glycolysis as a feature of cancer cells. A wide range of techniques have elucidated the complexity and heterogeneity in preclinical models and clinical studies. What emerges are the large differences between tissues, tumour types and intratumour heterogeneity. However, synergies with inhibition of metabolic pathways have been found for many drugs and therapeutic approaches, and a critical role of window studies and translational trial design is key to success.

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Determinants of vitamin D status in Kenyan calves

Scientific Reports ◽

10.1038/s41598-020-77209-5 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Rebecca Callaby ◽

Emma Hurst ◽

Ian Handel ◽

Phil Toye ◽

Barend M. de C. Bronsvoort ◽

...

Keyword(s):

Infectious Disease ◽

Vitamin D ◽

Health Outcomes ◽

Critical Role ◽

Subsequent Development ◽

Vitamin D Metabolites ◽

Vitamin D Status ◽

Skeletal Health ◽

A Genome ◽

Wide Range

AbstractVitamin D plays a critical role in calcium homeostasis and in the maintenance and development of skeletal health. Vitamin D status has increasingly been linked to non-skeletal health outcomes such as all-cause mortality, infectious diseases and reproductive outcomes in both humans and veterinary species. We have previously demonstrated a relationship between vitamin D status, assessed by the measurement of serum concentrations of the major vitamin D metabolite 25 hydroxyvitamin D (25(OH)D), and a wide range of non-skeletal health outcomes in companion and wild animals. The aims of this study were to define the host and environmental factors associated with vitamin D status in a cohort of 527 calves from Western Kenya which were part of the Infectious Disease of East African Livestock (IDEAL) cohort. A secondary aim was to explore the relationship between serum 25(OH)D concentrations measured in 7-day old calves and subsequent health outcomes over the following 12 months. A genome wide association study demonstrated that both dietary and endogenously produced vitamin D metabolites were under polygenic control in African calves. In addition, we found that neonatal vitamin D status was not predictive of the subsequent development of an infectious disease event or mortality over the 12 month follow up period.

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