Evolutionary deletions within the SARS-CoV-2 genome as signature trends for virus fitness and adaptation.

Coronaviruses are large RNA viruses that can infect and spread among humans and animals. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for coronavirus disease 2019, has evolved since its first detection in December 2019. Deletions are a common occurrence in SARS-CoV-2 evolution, particularly in specific genomic sites, and may be associated with the emergence of highly competent lineages. While deletions typically have a negative impact on viral fitness, some persist and become fixed in viral populations, indicating that they may confer advantageous benefits for the virus's adaptive evolution. This work presents a literature review and data analysis on structural losses in the SARS-CoV-2 genome and the potential relevance of specific signatures for enhanced viral fitness and spread.

Genomic Analysis of Surfactant-Producing Bacillus vallismortis TIM68: First Glimpse at Species Pangenome and Prediction of New Plipastatin-Like Lipopeptide.

Surfactants are applied in several industrial processes when the modification of interface activity and the stability of colloidal systems are required. Lipopeptides are a class of microbial biosurfactants produced by species of the Bacillus genus. The present study aimed at assembling and analyzing the genome of a new Bacillus vallismortis strain, TIM68, that was shown to produce surfactant lipopeptides. The draft genome was also screened for common virulence factors and antibiotics resistance genes to investigate the strain biosafety. Comparative genomics analyses, i.e., synteny, average nucleotide identity (ANI), and pangenome, were also carried out using strain TIM68 and publicly available B. vallismortis complete and partial genomes. Three peptide synthetase operons were found in TIM68 genome, and they were surfactin A, mojavensin, and a novel plipastatin-like lipopeptide named vallisin. No virulence factors that render pathogenicity to the strain have been identified, but a region of prophage, that may contain unknown pathogenic factors, has been predicted. The pangenome of the species was characterized as closed, with 57% of genes integrating the core genome. The results obtained here on the genetic potential of TIM68 strain should contribute to its exploration in biotechnological applications.

Genomic surveillance: Circulating lineages and genomic variation of SARS-CoV-2 in early pandemic in Ceará state, Northeast Brazil.

In the Northeast of Brazil, Ceará was the second state most impacted by COVID-19 in number of cases and death rate. Despite that, the early dynamics of the pandemic in Ceará was not yet well understood due the low genomic surveillance of SARS-CoV-2 in 2020. In this study, we analyze the circulating lineages and the genomic variation of the virus in Ceará state. Thirty-four genomes were sequenced and combined with sequences available in GISAID database from March 2020 to June 2021 to compose the study dataset. The most prevalent lineages detected were B.1.1.33, in 2020, and P.1, in 2021. Other lineages were found, such as P.2, sublineages of P.1, B.1, B.1.1, B.1.1.28 and B.1.212. Analyzing the mutations, a total of 202 single-nucleotide polymorphisms (SNPs) were identified among the 34 genomes sequenced, of which 127 were missense, 74 synonymous, and one was a nonsense mutation. Among the missense mutations, C14408T, A23403G, T27299C, G28881A G28883C, and T29148C were the most prevalent within the dataset. Although SARS-CoV-2 sequencing data was limited in 2020, our results could provide insights to better understand the genetic diversity of the circulating lineages in Ceará.