Structural Analysis of the SARS-CoV-2 Omicron Variant Proteins

The spread of the latest SARS-CoV-2 variant Omicron is particularly concerning because of the large number of mutations present in its genome and lack of knowledge about how these mutations would affect the current SARS-CoV-2 vaccines and treatments.Here,by performing phylogenetic analysis using the Omicron spike(S)protein sequence,we found that the Omicron S protein presented the longest evolutionary distance in relation to the other SARS-CoV-2 variants.We predicted the structures of S,M,and N proteins of the Omicron variant using AlphaFold2 and investigated how the mutations have affected the S protein and its parts,S1 NTD and RBD,in detail.We found many amino acids on RBD were mutated,which may influence the interactions between the RBD and ACE2,while also showing the S309 antibody could still be capable of neutralizing Omicron RBD.The Omicron S1 NTD structures display significant differences from the original strain,which could lead to reduced recognition by antibodies resulting in potential immune escape and decreased effectiveness of the existing vaccines.However,this study of the Omicron variant was mainly limited to structural predictions,and these findings should be explored and verified by subsequent experiments.This study provided basic data of the Omicron protein structures that lay the groundwork for future studies related to the SARS-CoV-2 Omicron variant.

Structural Comparison and Drug Screening of Spike Proteins of Ten SARS-CoV-2 Variants

SARS-CoV-2(severe acute respiratory syndrome coronavirus 2)has evolved many variants with stronger infectivity and immune evasion than the original strain,including Alpha,Beta,Gamma,Delta,Epsilon,Kappa,lota,Lambda,and 21H strains.Amino acid mutations are enriched in the spike protein of SARS CoV-2.which plays a crucial role in cell infetion.However,the impact of these mutations on protein structure and function is unclear.Understanding the pathophysiology and pandemic feaures of these SARS-CoV-2 variants requires knowledge of the spike protein structures.Here,we obtained the spike protein structures of 10 main globally endemic SARS CoV-2 strains using AlphaFold2.The clustering analysis based on structural similarity revealed the unique features of the mainly pandemic SARS CoV-2 Delta variants.indicating that structural clusters can reflect the current characteristics of the epidemic more accurately than those based on the protein sequence.The analysis of the binding afinities of ACE2-RBD,antibody-NTD,and antibody-RBD complexes in the different variants revealed that the recognition of antibodies against SI NTD and RBD was decreased in the variants,especally the Delta variant compared with the original strain,which may induce the immune evasion of SARS-CoV-2 variants.Furthermore,by virtual screening the ZINC database against a high-accuracy predicted structure of Delta spike protein and experimental validation,we identified multiple compounds that target S1 NTD and RBD,which might contribute towards the development of clinical anti-SARS-CoV-2 medicines.Our findings provided a basic foundation for future in vitro and in vivo investigations that might speed up the development of potential therapies for the SARS-CoV-2 va riants.

Scrutinizing the causal relationship between schizophrenia and vitamin supplementation:a Mendelian randomization study

Objective: Observational studies have reported malnutrition and vitamin deficiency in patients with schizophrenia (SZ), which can lead to serious metabolic syndromes and decrease anti-psychiatric drug outcomes. Whereas, vitamin intake along with psychiatric medication can enhance the medication outcomes. However, it is still unknown if SZ induces vitamin deficiency. Herein, we conduct the Mendelian randomization analysis to explore the causal relationship between schizophrenia and vitamins supplementation.Methods: We retrieved the genome-wide summary statistical data for schizophrenia from recent SZ GWAS data (43,175 cases and 65,166 controls) and vitamins supplementation GWAS data from Neale’s GWAS datasets (more than 337,000 samples from the European population) and performed a two-sample Mendelian randomization analysis to determine the causal association of SZ with vitamin supplementation, in addition, we conduct the sensitivity analysis to obtain reliable results and remove confounding bias.Results: SZ have causal relationships with vitamins A, B, C, D, and E (SZ/vitamin A: β = 0.002, se= 0.001, 95% confidence interval (CI): 0.001 to 0.004,P= 1.41E-05, heterogeneityP= 0.4486;SZ/vitamin B: β= 0.004, se= 0.001, 95% CI: 0.002-0.005,P= 7.0E-05, heterogeneityP= 0.2217;SZ/vitamin C: β= 0.004, se= 0.001, 95% CI: 0.002-0.007,P= 0.001, heterogeneityP= 0.1349;SZ/vitamin D: β= 0.003, se= 0.001, 95% CI: 0.002-0.005,P= 0.001, heterogeneityP= 0.433;SZ/vitamin E: β= 0.003, se= 0.001, 95% CI: 0.002-0.005,P= 5.0E-05, heterogeneityP= 0.1382).Conclusion: Our findings suggest that vitamin levels and supplementation should be carefully controlled in patients with SZ, which in turn may enhance the therapeutic effects of antipsychotic drug treatments.