Genomic Surveillance of SARS-CoV-2 in Healthcare Workers: A Critical Sentinel Group for Monitoring the SARS-CoV-2 Variant Shift.

SARS-CoV-2 genome surveillance is important for monitoring risk groups and health workers as well as data on new cases and mortality rate due to COVID-19. We characterized the circulation of SARS-CoV-2 variants from May 2021 to April 2022 in the state of Santa Catarina, southern Brazil, and evaluated the similarity between variants present in the population and healthcare workers (HCW). A total of 5291 sequenced genomes demonstrated the circulation of 55 strains and four variants of concern (Alpha, Delta, Gamma and Omicron-sublineages BA.1 and BA.2). The number of cases was relatively low in May 2021, but the number of deaths was higher with the Gamma variant. There was a significant increase in both numbers between December 2021 and February 2022, peaking in mid-January 2022, when the Omicron variant dominated. After May 2021, two distinct variant groups (Delta and Omicron) were observed, equally distributed among the five Santa Catarina mesoregions. Moreover, from November 2021 to February 2022, similar variant profiles between HCW and the general population were observed, and a quicker shift from Delta to Omicron in HCW than in the general population. This demonstrates the importance of HCW as a sentinel group for monitoring disease trends in the general population.

First record of Trypanosoma evansi DNA in Dichelacera alcicornis and Dichelacera januarii (Diptera: Tabanidae) flies in South America.

BACKGROUND: Trypanosoma evansi infects a large number of wild and domestic animals and causes a spoliative disease known as surra. It is mechanically transmitted, mainly by biting flies of the genera Tabanus and Stomoxys. The detection of T. evansi DNA in the feeding apparatus of Dichelacera alcicornis and Dichelacera januarii from South America is reported, to the best of our knowledge, for the first time. METHODS: Tabanids were collected weekly from February 2018 to February 2019 from two sites. The feeding apparatus was removed and DNA extraction, polymerase chain reaction and sequencing were performed. RESULTS: A 205-base pair fragment of the variant surface protein RoTat 1.2 gene, confirmed by DNA sequencing, was amplified from the feeding apparatus of D. alcicornis and D. januarii. CONCLUSIONS: This is, to the best of our knowledge, the first record of T. evansi DNA in South American tabanids.

Trypanosoma evansi secretome carries potential biomarkers for Surra diagnosis.

Trypanosoma evansi is a parasite that is phylogenetically close to Trypanosoma brucei and is the causative agent of a disease known as surra. Surra is responsible for a high mortality rate in livestock and large economic losses in the Americas, Africa, and Asia. This work aimed to analyze in vitro secreted proteins from T. evansi and identify potential treatment and diagnostic biomarkers for surra diagnosis. Two groups were used. In one group the parasites were purified using a DEAE-Cellulose column and maintained in a secretion medium while in the other group the parasites were not purified. Each group was further divided to be maintained at either 37 °C or 27 °C. We identified 246 proteins through mass spectrometry and found that the temperature appears to modulate protein secretion. We found minimal variations in the protein pools from pure and non-purified sets. We observed an emphasis on proteins associated to vesicles, glycolysis, and cellular homeostasis through the enrichment of GO. Also, we found that most secretome proteins share homologous proteins with T. b. brucei, T. b. gambiense, T. vivax, T. equiperdum, and T. b. rhodesiense secretome but unique T. evansi epitopes with potential biomarkers for surra diagnosis were detected. SIGNIFICANCE: Trypanosoma evansi is a parasite of African origin that is phylogenetically close to Trypanosoma brucei. As with other trypanosomatids and blood parasites, its infection causes non-pathognomonic symptoms, which makes its diagnosis difficult. One great problem is the fact that no diagnostic test differentiates between Trypanosoma equiperdum and T. evansi, which is a problem in South America and Asia, and Africa. Thus, it is urgent to study the biochemistry of the parasite to discover proteins that can be used for differential diagnosis or be possible therapeutic targets. In addition, the study of the secretome can point out proteins that are used by the parasite in its interactions with the host, helping to understand the progression of the disease.

AnnotaPipeline: An integrated tool to annotate eukaryotic proteins using multi-omics data.

Assignment of gene function has been a crucial, laborious, and time-consuming step in genomics. Due to a variety of sequencing platforms that generates increasing amounts of data, manual annotation is no longer feasible. Thus, the need for an integrated, automated pipeline allowing the use of experimental data towards validation of in silico prediction of gene function is of utmost relevance. Here, we present a computational workflow named AnnotaPipeline that integrates distinct software and data types on a proteogenomic approach to annotate and validate predicted features in genomic sequences. Based on FASTA (i) nucleotide or (ii) protein sequences or (iii) structural annotation files (GFF3), users can input FASTQ RNA-seq data, MS/MS data from mzXML or similar formats, as the pipeline uses both transcriptomic and proteomic information to corroborate annotations and validate gene prediction, providing transcription and expression evidence for functional annotation. Reannotation of the available Arabidopsis thaliana, Caenorhabditis elegans, Candida albicans, Trypanosoma cruzi, and Trypanosoma rangeli genomes was performed using the AnnotaPipeline, resulting in a higher proportion of annotated proteins and a reduced proportion of hypothetical proteins when compared to the annotations publicly available for these organisms. AnnotaPipeline is a Unix-based pipeline developed using Python and is available at: https://github.com/bioinformatics-ufsc/AnnotaPipeline.

EpiBuilder: A Tool for Assembling, Searching, and Classifying B-Cell Epitopes.

Epitopes are portions of a protein that are recognized by antibodies. These small amino acid sequences represent a significant breakthrough in a branch of bioinformatics called immunoinformatics. Various software are available for linear B-cell epitope (BCE) prediction such as ABCPred, SVMTrip, EpiDope, and EpitopeVec; a well-known BCE predictor is BepiPred-2.0. However, despite the prediction, there are several essential steps, such as epitope assembly, evaluation, and searching for epitopes in other proteomes. Here, we present EpiBuilder (https://epibuilder.sourceforge.io), a user friendly software that assists in epitope assembly, classifying and searching using input results of BepiPred-2.0. EpiBuilder generates several output results from these data and supports a proteome-wide processing approach. In addition, this software provides the following features: Chou & Fasman beta-turn prediction, Emini surface accessibility prediction, Karplus and Schulz flexibility prediction, Kolaskar and Tongaonkar antigenicity, Parker hydrophilicity prediction, N-glycosylation domains, and hydropathy. These information generate a unique topology for each epitope, visually demonstrating its characteristics. The software can search the entire epitope sequence in various FASTA files, and it allows to use BLASTP to identify epitopes that eventually have sequence variations. As an EpiBuilder application, we developed a epitope dataset from the protozoan Trypanosoma brucei gambiense, the gram-positive bacterium Clostridioides difficile, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Emergence of Two Distinct SARS-CoV-2 Gamma Variants and the Rapid Spread of P.1-like-II SARS-CoV-2 during the Second Wave of COVID-19 in Santa Catarina, Southern Brazil.

The western mesoregion of the state of Santa Catarina (SC), Southern Brazil, was heavily affected as a whole by the COVID-19 pandemic in early 2021. This study aimed to evaluate the dynamics of the SARS-CoV-2 virus spreading patterns in the SC state from March 2020 to April 2021 using genomic surveillance. During this period, there were 23 distinct variants, including Beta and Gamma, among which the Gamma and related lineages were predominant in the second pandemic wave within SC. A regionalization of P.1-like-II in the Western SC region was observed, concomitant to the increase in cases, mortality, and the case fatality rate (CFR) index. This is the first evidence of the regionalization of the SARS-CoV-2 transmission in SC and it highlights the importance of tracking the variants, dispersion, and impact of SARS-CoV-2 on the public health systems.

Exoproteomic analysis of two MLST clade 2 strains of Clostridioides difficile from Latin America reveal close similarities.

Clostridioides difficile BI/NAP1/ribotype 027 is an epidemic hypervirulent strain found worldwide, including in Latin America. We examined the genomes and exoproteomes of two multilocus sequence type (MLST) clade 2 C. difficile strains considered hypervirulent: ICC-45 (ribotype SLO231/UK[CE]821), isolated in Brazil, and NAP1/027/ST01 (LIBA5756), isolated during a 2010 outbreak in Costa Rica. C. difficile isolates were cultured and extracellular proteins were analyzed using high-performance liquid chromatography-tandem mass spectrometry. Genomic analysis revealed that these isolates shared most of the gene composition. Only 83 and 290 NAP1/027 genes were considered singletons in ICC-45 and NAP1/027, respectively. Exoproteome analysis revealed 197 proteins, of which 192 were similar in both strains. Only five proteins were exclusive to the ICC-45 strain. These proteins were involved with catalytic and binding functions and indirectly interacted with proteins related to pathogenicity. Most proteins, including TcdA, TcdB, flagellin subunit, and cell surface protein, were overrepresented in the ICC-45 strain; 14 proteins, including mature S-layer protein, were present in higher proportions in LIBA5756. Data are available via ProteomeXchange with identifier PXD026218. These data show close similarity between the genome and proteins in the supernatant of two strains with hypervirulent features isolated in Latin America and underscore the importance of epidemiological surveillance of the transmission and emergence of new strains.

Serum proteomic signature of Trypanosoma evansi -infected mice for identification of potential biomarkers.

Trypanosoma evansi is the agent of "surra," a trypanosomosis endemic in many areas worldwide. Trypanosoma proteins released/secreted during infection are attractive biomarkers for disease detection and monitoring. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), we performed a comprehensive analysis of the serum proteome of mice infected with T.evansi and detected changes in the abundance of parasite and host serum proteins during infection. Following bioinformatics analysis, 30 T. evansi proteins were identified in the mice serum including known targets such as pyruvate kinase 1, ß-tubulin, actin A, heat shock protein 70, and cyclophilin A. We also identified two exclusive VSG epitopes which are novel putative biomarker targets. In addition, upregulation of 31 mouse proteins, including chitinase-like protein 3 and monocyte differentiation antigen CD14, were observed. Identification of parasite-specific biomarkers in the host serum is critical for the development of reliable serological/ assays for differential diagnosis.

Extremophile Microbial Communities and Enzymes for Bioenergetic Application Based on Multi-Omics Tools.

Genomic and proteomic advances in extremophile microorganism studies are increasingly demonstrating their ability to produce a variety of enzymes capable of converting biomass into bioenergy. Such microorganisms are found in environments with nutritional restrictions, anaerobic environments, high salinity, varying pH conditions and extreme natural environments such as hydrothermal vents, soda lakes, and Antarctic sediments. As extremophile microorganisms and their enzymes are found in widely disparate locations, they generate new possibilities and opportunities to explore biotechnological prospecting, including biofuels (biogas, hydrogen and ethanol) with an aim toward using multi-omics tools that shed light on biotechnological breakthroughs.