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Santos FRDS, de Azevedo MSP, Bielavsky M, da Costa HHM, Ribeiro DG, Nascimento GGD, Marcondes GMP, de Castro BP, de Lima Neto DF, Prudencio CR. Mutational profile confers increased stability of SARS-CoV-2 spike protein in Brazilian isolates. J Biomol Struct Dyn 2022; 40:13184-13189. [PMID: 34633892 DOI: 10.1080/07391102.2021.1982775] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Spike (S) protein has been recognized as a promising molecular target for diagnostic, vaccines and antiviral drugs development for COVID-19. In this study, we analyzed the most predominant mutations in the S protein of Brazilian isolates and predicted the effect of these amino acid alterations to protein conformation. A total of 25,924 sequences were obtained from GISAID for five regions of Brazilian territory (Midwest, North, Northeast, South, and Southeast), according to exclusion criteria. Most of the SARS-CoV-2 isolates belongs to the G clade and showed a large occurrence of D614G, N501Y and L18F substitutions. Prediction effects of these amino acid substitutions on the structure dynamics of the spike protein indicated a positive ΔΔG values and negative ΔΔSVib in most cases which is associated to structural stabilization and flexibility reduction of the S protein. Mutations E484K, N501Y and K417N belong to several SARS-CoV-2 variants of concern such as Alpha, Beta, Gamma and Delta, and showed high incidence among Brazilian isolates. These mutations have been described to increase RBD affinity to ACE-2 host and abolishment of RBD affinity to potent neutralizing ant-RBD. The increase in rates of infection and reinfection requires continuous genomic surveillance studies in order to characterize emerging mutations and monitor vaccine efficacy, and thus consideration structural data and dynamics in the observed phenotypes.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
| | | | - Monica Bielavsky
- Laboratory of Immunotechnology, Center of Immunology, Adolfo Lutz Institute, São Paulo, SP, Brazil
| | | | - Daniela Gomes Ribeiro
- Laboratory of Immunotechnology, Center of Immunology, Adolfo Lutz Institute, São Paulo, SP, Brazil
| | | | | | | | - Daniel Ferreira de Lima Neto
- Coordenação-Geral de Laboratórios de Saúde Pública, Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasília, Distrito Federal, Brazil.,Laboratório de Termodinâmica de Proteínas, Departamento de Bioquímica, Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Carlos Roberto Prudencio
- Laboratory of Immunotechnology, Center of Immunology, Adolfo Lutz Institute, São Paulo, SP, Brazil
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Abstract
Cassava rootstocks of varieties UnB 201 and UnB 122 grafted with scions of Manihot fortalezensis were prepared for anatomic study. The roots were cut, stained with safranin and alcian blue, and examined microscopically, comparing them with sections taken from ungrafted roots. There was a significant decrease in number of pericyclic fibers, vascular vessels and tyloses in rootstocks. They exhibited significant larger vessels. These changes in anatomic structure are a consequence of genetic effects caused by transference of genetic material from scion to rootstock. The same ungrafted species was compared. This is the first report on anatomic changes due to grafting in cassava.
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Affiliation(s)
- N Bomfim
- Departamento de Botânica, Universidade de Brasília, Brasília, DF, Brasil
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Abstract
A molecular, anatomical and cytogenetic study of an interspecific hybrid between Manihot esculenta (cassava) and the wild species M. oligantha was carried out. Cytogenetics revealed relatively complete chromosome pairing and high viability of the pollen grains. Ovule structure examined by the clearing method showed polyembryony in 2.7% of the ovules. Doubling of the chromosome number resulted in an increase in polyembryony of up to 18% and a reduction in pollen viability. Multivalent formation was also observed. An anatomical study of stems of diploid and tetraploid hybrids showed a larger number of vascular bundles in the tetraploid type.
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Affiliation(s)
- N M A Nassar
- Departamento de Genética e Morfologia, Universidade de Brasília, Campus Darcy Ribeiro, Brasília, DF, Brasil.
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Stolf NA, Armelin E, Barretto AC, Mady C, Ribeiro DG, Macruz R, Pillegi F, Bittencourt D, Zerbini EJ. [Endomyocardial biopsy of the right ventricle-technic and preliminary results]. Arq Bras Cardiol 1979; 32:221-5. [PMID: 508103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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