Publications by authors named "Robson F De Souza"

With the advent of advanced sequencing technologies, new insights into the genomes of pathogens, including those in the genus Curtobacterium, have emerged. This research investigates a newly isolated C. flaccumfaciens strain 208 (Cf208) from Arthrocereus glaziovii, and endemic plant from Iron Quadrangle.

View Article and Find Full Text PDF

Proteases represent common targets in combating infectious diseases, including COVID-19. The 3-chymotrypsin-like protease (3CLpro) is a validated molecular target for COVID-19, and it is key for developing potent and selective inhibitors for inhibiting viral replication of SARS-CoV-2. In this review, we discuss structural relationships and diverse subsites of 3CLpro, shedding light on the pivotal role of dimerization and active site architecture in substrate recognition and catalysis.

View Article and Find Full Text PDF
Article Synopsis
  • Periodontitis is caused by an imbalance in oral bacteria, leading to inflammation and bone loss, which researchers investigated using a murine model.
  • The study assessed the effects of the probiotic LA5 on both bone loss and changes in the oral and gut microbiomes after infection with periodontopathic bacteria.
  • Results showed that LA5 reduced bone loss and countered dysbiosis in the microbiomes, suggesting its potential as a treatment for periodontitis.
View Article and Find Full Text PDF

Herein, we present a novel esterase enzyme, Ade1, isolated from a metagenomic library of Amazonian dark earths soils, demonstrating its broad substrate promiscuity by hydrolyzing ester bonds linked to aliphatic groups. The three-dimensional structure of the enzyme was solved in the presence and absence of substrate (tributyrin), revealing its classification within the α/β-hydrolase superfamily. Despite being a monomeric enzyme, enzymatic assays reveal a cooperative behavior with a sigmoidal profile (initial velocities vs substrate concentrations).

View Article and Find Full Text PDF

Herein, we conducted simulations of trimeric Spike from several SARS-CoV-2 variants of concern (Delta and Omicron sub-variants BA.2, BA.5, and BQ.

View Article and Find Full Text PDF

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron is currently the most prevalent SARS-CoV-2 variant worldwide. Herein, we calculated molecular dynamics simulations of the trimeric spike and Spike for 300 ns. Our results show that Spike has more conformational flexibility than Spike.

View Article and Find Full Text PDF

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is evolving with mutations in the spike protein, especially in the receptor-binding domain (RBD). The failure of public health measures in some countries to contain the spread of the disease has given rise to novel viral variants with increased transmissibility. However, key questions about how quickly the variants can spread remain unclear.

View Article and Find Full Text PDF

Background: Public health research frequently requires the integration of information from different data sources. However, errors in the records and the high computational costs involved make linking large administrative databases using record linkage (RL) methodologies a major challenge.

Methods: We present Tucuxi-BLAST, a versatile tool for probabilistic RL that utilizes a DNA-encoded approach to encrypt, analyze and link massive administrative databases.

View Article and Find Full Text PDF

Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOC) are constantly threatening global public health. With no end date, the pandemic persists with the emergence of novel variants that threaten the effectiveness of diagnostic tests and vaccines. Mutations in the Spike surface protein of the virus are regularly observed in the new variants, potentializing the emergence of novel viruses with different tropism from the current ones, which may change the severity and symptoms of the disease.

View Article and Find Full Text PDF
Article Synopsis
  • Inflammation influences microbial communities, yet its interaction with microorganisms in periodontitis is not well understood, prompting a study on the oral and fecal microbiomes of patients with the disease.
  • The research involved nine patients with stage 3 periodontitis and nine healthy controls, analyzing the composition of their oral biofilms and fecal samples via DNA sequencing, alongside correlating these findings with inflammatory markers in saliva.
  • Results showed significant differences in microbial diversity, with periodontitis patients exhibiting higher levels of harmful bacteria in both oral and fecal samples, and dysbiosis linking specific microbes to inflammatory responses, indicating a complex relationship between immune response and microbial composition in periodontitis.
View Article and Find Full Text PDF

pathogens are the causative agents of several severe crop diseases worldwide, including citrus Huanglongbing and potato zebra chip. These bacteria are endophytic and nonculturable, which makes experimental approaches challenging and highlights the need for bioinformatic analysis in advancing our understanding about pathogenesis. Here, we performed an in-depth comparative phylogenomic analysis of the pathogens and their free-living, nonpathogenic, ancestral species, aiming to identify major genomic changes and determinants associated with their evolutionary transitions in living habitats and pathogenicity.

View Article and Find Full Text PDF

The current outbreak of COVID-19 is leading an unprecedented scientific effort focusing on targeting SARS-CoV-2 proteins critical for its viral replication. Herein, we performed high-throughput virtual screening of more than eleven thousand FDA-approved drugs using backpropagation-based artificial neural networks ( = 0.60, = 0.

View Article and Find Full Text PDF

The SARS-CoV-2 pandemic has already killed more than one million people worldwide. To gain entry, the virus uses its Spike protein to bind to host hACE-2 receptors on the host cell surface and mediate fusion between viral and cell membranes. As initial steps leading to virus entry involve significant changes in protein conformation as well as in the electrostatic environment in the vicinity of the Spike/hACE-2 complex, we explored the sensitivity of the interaction to changes in ionic strength through computational simulations and surface plasmon resonance.

View Article and Find Full Text PDF

is a complex formed by , var. , and . Members of this complex are opportunistic pathogens closely related to , , and , all members of a multidrug-resistant clade.

View Article and Find Full Text PDF
Article Synopsis
  • Type VI secretion systems (T6SSs) enable bacteria like Salmonella to inject toxic proteins, known as effectors, into rival bacteria, impacting their growth and viability.
  • The study focuses on the T6SS effector Tlde1, which disrupts target cells by damaging their cell structure and function, and can be neutralized by its related immunity protein Tldi1.
  • Tlde1 shows enzymatic activity similar to l,d-transpeptidases, suggesting it cleaves essential components of the bacterial cell wall, and its homologs are widely found in various Proteobacteria, indicating a common strategy for bacterial competition.
View Article and Find Full Text PDF

is the main causative agent of zoonotic tuberculosis in humans and frequently devastates livestock and wildlife worldwide. Previous studies suggested the existence of genetic groups of strains based on limited DNA markers (a.k.

View Article and Find Full Text PDF

Background: Sugarcane cultivars are polyploid interspecific hybrids of giant genomes, typically with 10-13 sets of chromosomes from 2 Saccharum species. The ploidy, hybridity, and size of the genome, estimated to have >10 Gb, pose a challenge for sequencing.

Results: Here we present a gene space assembly of SP80-3280, including 373,869 putative genes and their potential regulatory regions.

View Article and Find Full Text PDF

Multidrug-resistant (MDR) (Kp) is a major bacterial pathogen responsible for hospital outbreaks worldwide, mainly via the spread of high-risk clones and epidemic resistance plasmids. In this study, we evaluated the molecular epidemiology and β-lactam resistance mechanisms of MDR-Kp strains isolated in a Brazilian academic care hospital. We used whole-genome sequencing to study drug resistance mechanisms and their relationships with a carbapenemase-producing (KPC) Kp outbreak.

View Article and Find Full Text PDF

Carnivorous rainbow trout exhibit prolonged postprandial hyperglycemia when fed a diet exceeding 20% carbohydrate content. This poor capacity to utilize carbohydrates has led to rainbow trout being classified as "glucose-intolerant" (GI). The metabolic phenotype has spurred research to identify the underlying cellular and molecular mechanisms of glucose intolerance, largely because carbohydrate-rich diets provide economic and ecological advantages over traditionally used fish meal, considered unsustainable for rainbow trout aquaculture operations.

View Article and Find Full Text PDF

The second messenger cyclic diguanylate monophosphate (c-di-GMP) is a central regulator of bacterial lifestyle, controlling several behaviors, including the switch between sessile and motile states. The c-di-GMP levels are controlled by the interplay between diguanylate cyclases (DGCs) and phosphodiesterases, which synthesize and hydrolyze this second messenger, respectively. These enzymes often contain additional domains that regulate activity via binding of small molecules, covalent modification, or protein-protein interactions.

View Article and Find Full Text PDF

causes bovine tuberculosis and is the main organism responsible for zoonotic tuberculosis in humans. We performed the sequencing, assembly and annotation of a Brazilian strain of named SP38, and performed comparative genomics of genomes deposited in GenBank. SP38 has a traditional tuberculous mycobacterium genome of 4,347,648 bp, with 65.

View Article and Find Full Text PDF

Leptospira interrogans serovar Copenhageni is a human pathogen that causes leptospirosis, a worldwide zoonosis. The L. interrogans genome codes for a wide array of potential diguanylate cyclase (DGC) enzymes with characteristic GGDEF domains capable of synthesizing the cyclic dinucleotide c-di-GMP, known to regulate transitions between different cellular behavioral states in bacteria.

View Article and Find Full Text PDF

Intense biological conflicts between prokaryotic genomes and their genomic parasites have resulted in an arms race in terms of the molecular "weaponry" deployed on both sides. Using a recursive computational approach, we uncovered a remarkable class of multidomain proteins with 2 to 15 domains in the same polypeptide deployed by viruses and plasmids in such conflicts. Domain architectures and genomic contexts indicate that they are part of a widespread conflict strategy involving proteins injected into the host cell along with parasite DNA during the earliest phase of infection.

View Article and Find Full Text PDF

The complete plastome sequencing is an efficient option for increasing phylogenetic resolution and evolutionary studies, as well as may greatly facilitate the use of plastid DNA markers in plant population genetic studies. Merostachys and Guadua stand out as the most common and the highest potential utilization bamboos indigenous of Brazil. Here, we sequenced the complete plastome sequences of the Brazilian Guadua chacoensis and Merostachys sp.

View Article and Find Full Text PDF