ABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new member of the Coronaviridae family, triggering more than 190 million cases and more than two million deaths in European societies. Emerging the new variants due to mutations in genomic regions is foremost responsible for influencing the infectivity and mortality potential of such a virus. In the current study, we considered mutations among spike (S), envelope (E), membrane (M), and nucleocapsid (N) proteins of SARS-CoV-2 in the Europe continent by exploring the frequencies of mutations and the timeline of emerging them. For this purpose, Amino-acid sequences (AASs) were gathered from the GISAID database, and Mutation tracking was performed by detecting any difference between samples and a reference sequence; Wuhan-2019. In the next step, we compared the achieved results with worldwide sequences. 8.6%, 63.6%, 24.7%, and 1.7% of S, E, M, and N samples did not demonstrate any mutation among European countries. Also, the regions of 508 to 635 AA, 7 to 14 AA, 66 to 88 AA, and 164 to 205 AA in S, E, M, and N samples contained the most mutations relative to the total AASs in both Europe AASs and worldwide samples. D614G, A222V, S477N, and L18F were the first to fifth frequent mutations in S AASs among European samples, and T9I, I82T, and R203M were the first frequent mutations among E, M, and S AASs of the Europe continent. Investigating the mutations among structural proteins of SARS-CoV-2 can improve the strength of therapeutic and diagnostic strategies to efficient combat the virus and even maybe efficient in predicting new emerging variants of concern.
ABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a role in the mortality of more than 6 million people worldwide. This virus owns the genome, which contains four structural proteins, including spike (S), envelope (E), membrane (M), and nucleocapsid (N). The occurrence of structural mutations can induce the emergence of new variants. Depending on the mutations, the variants may display different patterns of infectivity, mortality, and sensitivity toward drugs and vaccines. In this study, we analyzed samples of amino-acid sequences (AASs) for structural proteins from the coronavirus 2019 (COVID-19) declaration as a pandemic to April 2022 among American countries. The analysis process included considering mutations frequencies, locations, and evolutionary trends utilizing sequence alignment to the reference sequence. In the following, the results were compared with the same analyses among the samples of the entire world. Results displayed that despite samples of North America and international countries that own the region of 508 to 635 with the highest mutation frequency among S AASs, the region with the same characteristic was concluded as 1 to 127 in South America. Besides, the most frequent mutations in S, E, M, and N proteins from North America and worldwide samples were concluded as D614G, T9I, I82T, and R203M. In comparison, R203K was the first frequent mutation in N samples in South America. Widely comparing mutations between North America and South America and between the Americas and the world can help scientists introduce better drug and vaccine development strategies.
