Biology subjects

Pedrosa-Silva, F.

Publications and source records attributed to Pedrosa-Silva, F..

10 recordsLinked to original sources

bioRxiv2025

Genomic insights into the genus Pantoea: biotechnological potential and lifestyle diversity

Pantoea is a genus of Gram-negative bacteria isolated from diverse environments. Over time, it has drawn considerable attention for its potential to promote plant growth. However, its biotechnological application is complicated by high genomic plasticity, which underlies both its beneficial traits and its ability to cause disease in a wide range of plants, as well as occasional opportunistic infections in humans, raising biosafety concerns. In this study, we conducted a comparative genomic analysis of all publicly available Pantoea genomes. Our goals were to refine taxonomic classifications and to identify genes linked to biotechnological potential, virulence, and antibiotic resistance, thereby clarifying lifestyle strategies within the genus. We found that plant growth-promoting genes are widely conserved, particularly those involved in phosphate solubilization, phytohormone biosynthesis, and siderophore production. In contrast, traits such as nitrogen fixation and ACC deaminase activity were restricted to specific species. The resistome analysis revealed intrinsic resistance mechanisms conserved across the genus, primarily involving diverse efflux pump families and {beta}-lactamases conferring resistance to cephalosporins. In parallel, the pan-GWAS highlighted lifestyle-defining genetic markers, including the hrp/hrc genes encoding type III secretion system components, pepM (phosphoenolpyruvate mutase) associated with the production of a phytotoxin, and ibeB, an invasin linked to clinical infections. Together, our findings underscore both the biotechnological potential of Pantoea and the importance of genetic markers for distinguishing beneficial from pathogenic lifestyles, supporting the safe application of selected strains in biotechnology.

microbiology↗

bioRxiv2024

Cannabis Expression Atlas: a comprehensive resource for integrative analysis of Cannabis sativa L. gene expression

Cannabis sativa L., a plant originating from Central Asia, is a versatile crop with applications spanning textiles, construction, pharmaceuticals, and food products. This study aimed to compile and analyze publicly available Cannabis RNA-Seq data and develop an integrated database tool to help advance Cannabis research in various topics such as fiber production, cannabinoid biosynthesis, sex determination, and plant development. We identified 515 publicly available RNA-Seq samples that, after stringent quality control, resulted in a high-quality dataset of 394 samples. Utilizing the Jamaican Lion genome as reference, we constructed a comprehensive database and developed the Cannabis Expression Atlas (https://cannatlas.venanciogroup.uenf.br/), a web application for visualization of gene expression, annotation, and functional classification. Key findings include the quantification of 27,640 Cannabis genes and their classification into seven expression categories: not-expressed, low-expressed, housekeeping, tissue-specific, group-enriched, mixed, and expressed-in-all tissues. The study revealed substantial variability and coherence in gene expression across different tissues and chemotypes. We found 2,382 tissue-specific genes, including 177 transcription factors.. The Cannabis Expression Atlas constitutes a valuable tool for exploring gene expression patterns and offers insights into Cannabis biology, supporting research in plant breeding, genetic engineering, biochemistry, and functional genomics.

plant biology↗

bioRxiv2024

Comparative metagenomic profiling of seed-borne microbiomes in a landrace and a hybrid maize variety

The plant seed-borne microbiome comprises microorganisms vertically inherited from the mother plant. This microbiome is often linked to early-life protection and seedling growth promotion. Here, we compare the seed-borne bacteriomes of a commercial hybrid and a landrace maize variety. The landrace variety displays a more diverse seed-borne microbiome, featuring a variety of taxa across samples. In contrast, the microbiome of the hybrid variety is less diverse and more uniform across samples. Although both microbiomes lack a functional nitrogen fixation apparatus, we found a remarkably distinct presence of genes associated with phytohormone production and phosphate solubilization, particularly in the landrace variety. In addition, we recovered 18 metagenome-assembled genomes (MAGs), including four from potentially novel species. Collectively, our results allow a better understanding of the contrasting diversity between maize varieties and open important perspectives for designing synthetic microbial communities for agroecosystems.

plant biology↗

bioRxiv2023

The Soybean Expression Atlas v2: a comprehensive database of over 5000 RNA-seq samples

Soybean is a crucial crop worldwide, used as a source of food, feed, and industrial products due to its high protein and oil content. Previously, the rapid accumulation of soybean RNA-seq data in public databases and the computational challenges of processing raw RNA-seq data motivated us to develop the Soybean Expression Atlas, a gene expression database of over a thousand RNA-seq samples. Over the past few years, our database has allowed researchers to explore the expression profiles of important gene families, discover genes associated with agronomic traits, and understand the transcriptional dynamic of cellular processes. Here, we present the Soybean Expression Atlas v2, an updated version of our database with a 4-fold increase in the number of samples, featuring transcript- and gene-level transcript abundance matrices for 5481 publicly available RNA-seq samples. New features in our database include the availability of transcript-level abundance estimates and equivalence classes to explore differential transcript usage, abundance estimates in bias-corrected counts to increase the accuracy of differential gene expression analyses, a new web interface with improved data visualization and user experience, and a reproducible and scalable pipeline available as an R package. The Soybean Expression Atlas v2 is available at https://soyatlas.venanciogroup.uenf.br/, and it will accelerate soybean research, empowering researchers with high-quality and easily accessible gene expression data.

plant biology↗

bioRxiv2021

Genome sequencing of the vermicompost strain Stenotrophomonas maltophilia UENF-4GII and population structure analysis of the S. maltophilia Sm3 genogroup

The Stenotrophomonas maltophilia complex (Smc) is a cosmopolitan bacterial group that has been proposed an emergent multidrug-resistant pathogen. Taxonomic studies support the genomic heterogeneity of Smc, which comprises genogroups exhibiting a range of phenotypically distinct strains from different sources. Here, we report the genome sequencing and in-depth analysis of S. maltophilia UENF-4GII, isolated from vermicompost. This genome harbors a unique region encoding a penicillin-binding protein (pbpX) that was carried by a transposon, as well as horizontally-transferred genomic islands involved in anti-phage defense via DNA modification, and pili glycosylation. We also analyzed all available Smc genomes to investigate genes associated with resistance and virulence, niche occupation, and population structure. S. maltophilia UENF-4GII belongs to genogroup 3 (Sm3), which comprises three phylogenetic clusters (PC). Pan-GWAS analysis uncovered 471 environment-associated and 791 PC-associated genes, including antimicrobial resistance (e.g. blaL1 and blaR1) and virulence determinants (e.g. treS and katG) that provide insights on the resistance and virulence potential of Sm3 strains. Together, the results presented here provide the grounds for more detailed clinical and ecological investigations of S. maltophilia.

microbiology↗

bioRxiv2021

Integrating omics approaches to discover and prioritize candidate genes involved in oil biosynthesis in soybean

Soybean is one of the major sources of edible protein and oil. Oil content is a quantitative trait that is significantly determined by genetic and environmental factors. Over the past 30 years, a large volume of soybean genetic, genomic, and transcriptomic data have been accumulated. Nevertheless, integrative analyses of such data remain scarce, in spite of their importance for crop improvement. We hypothesized that the co-occurrence of genomic regions for oil-related traits in different studies may reveal more stable regions encompassing important genetic determinants of oil content and quality in soybean. We integrated publicly available data, obtained with distinct techniques, to discover and prioritize candidate genes involved in oil biosynthesis and regulation in soybean. We detected key fatty acid biosynthesis genes (e.g., BCCP and ACCase, FADs, KAS family proteins) and several transcripton factors, which are likely regulators of oil biosynthesis. In addition, we identified new candidates for seed oil accumulation and quality, such as Glyma.03G213300 and Glyma.19G160700, which encode a translocator protein and a histone acetyltransferase, respectively. Further, oil and protein genomic hotspots are strongly associated with breeding and not with domestication, suggesting that soybean domestication prioritized other traits. The genes identified here are promising targets for breeding programs and for the development of soybean lines with increased oil content and quality.

plant biology↗

bioRxiv2021

Characterization of cellular, biochemical and genomic features of the diazotrophic plant growth-promoting bacterium Azospirillum sp. UENF-412522, a novel member of the Azospirillum genus

Given their remarkable beneficial effects on plant growth, several Azospirillum isolates currently integrate the formulations of various commercial inoculants. Our research group isolated a new strain, Azospirillum sp. UENF-412522, from passion fruit rhizoplane. This isolate uses carbon sources that are partially distinct from closely-related Azospirillum isolates. Scanning electron microscopy analysis and population counts demonstrate the ability of Azospirillum sp. UENF-412522 to colonize the surface of passion fruit roots. In vitro assays demonstrate the ability of Azospirillum sp. UENF-412522 to fix atmospheric nitrogen, to solubilize phosphate and to produce indole-acetic acid. Passion fruit plantlets inoculated with Azospirillum sp. UENF-41255 showed increased shoot and root fresh matter, as well as root dry matter, further highlighting its biotechnological potential for agriculture. We sequenced the genome of Azospirillum sp. UENF-412522 to investigate the genetic basis of its plant-growth promotion properties. We identified the key nif genes for nitrogen fixation, the complete PQQ operon for phosphate solubilization, the acdS gene that alleviates ethylene effects on plant growth, and the napCAB operon, which produces nitrite under anoxic conditions. We also found several genes conferring resistance to common soil antibiotics, which are critical for Azospirillum sp. UENF-412522 survival in the rhizosphere. Finally, we also assessed the Azospirillum pangenome and highlighted key genes involved in plant growth promotion. A phylogenetic reconstruction of the genus was also conducted. Our results support Azospirillum sp. UENF-412522 as a good candidate for bioinoculant formulations focused on plant growth promotion in sustainable systems.

microbiology↗

bioRxiv2019

Systematic analysis of 1,298 RNA-Seq samples and construction of a comprehensive soybean (Glycine max) expression atlas

Soybean (Glycine max [L.] Merr.) is a major crop in animal feed and human nutrition, mainly for its rich protein and oil contents. The remarkable rise in soybean transcriptome studies over the past five years generated an enormous amount of RNA-seq data, encompassing various tissues, developmental conditions, and genotypes. In this study, we have collected data from 1,298 publicly available soybean transcriptome samples, processed the raw sequencing reads, and mapped them to the soybean reference genome in a systematic fashion. We found that 94% of the annotated genes (52,737/56,044) had detectable expression in at least one sample. Unsupervised clustering revealed three major groups, comprising samples from aerial, underground, and seed/seed-related parts. We found 452 genes with uniform and constant expression levels, supporting their roles as housekeeping genes. On the other hand, 1,349 genes showed heavily biased expression patterns towards particular tissues. A transcript-level analysis revealed that 95% (70,963/74,490) of the known transcripts overlap with those reported here, whereas 3,256 assembled transcripts represent potentially novel splicing isoforms. The dataset compiled here constitute a new resource for the community, which can be downloaded or accessed through a user-friendly web interface at http://venanciogroup.uenf.br/resources/. This comprehensive transcriptome atlas will likely accelerate research on soybean genetics and genomics.

plant biology↗

bioRxiv2019

Population structure and pangenome analysis of Enterobacter bugandensis uncover the presence of blaCTX-M-55, blaNDM-5 and blaIMI-1, along with sophisticated iron acquisition strategies

Enterobacter bugandensis is a recently described species that has been largely associated with nosocomial infections. Here, we report the genome of a non-clinical E. bugandensis strain. We used this and other several publicly available E. bugandensis genomes to obtain the species pangenome, investigate the conservation of important genes, and elucidate general population structure features of the species. Core- and whole-genome multilocus sequence typing (cgMLST and wgMLST, respectively) allowed the detection of five E. bugandensis phylogroups (PG-A to E). We found important antimicrobial resistance and virulence determinants associated with specific PGs, notably PG-A and PG-E. IncFII was the most prevalent plasmid replicon type in this species. We uncovered several extended-spectrum {beta}-lactamases, including blaCTX-M-55 and blaNDM-5, present in an IncX replicon type plasmid, described here for the first time in E. bugandensis. Genetic context analysis of blaNDM-5 revealed the resemblance of this plasmid with other IncX plasmids isolated from other bacteria from the same country. Further, three distinctive siderophore producing operons were found in the E. bugandensis pangenome: enterobactin (ent), aerobactin (iuc/iut), and salmochelin (iro). The latter operon is conserved in all PG-E isolates. Collectively, our findings provide novel insights on the lifestyle, physiology, antimicrobial, and virulence profiles of E. bugandensis.

genomics↗

bioRxiv2019

Genomic analysis unveils important aspects of population structure, virulence, and antimicrobial resistance in Klebsiella aerogenes

Klebsiella aerogenes is an important pathogen in healthcare-associated infections. Nevertheless, in comparison to other clinically important pathogens, K. aerogenes population structure, genetic diversity, and pathogenicity remain poorly understood. Here, we elucidate K. aerogenes clonal complexes (CCs) and genomic features associated with resistance and virulence. We present a detailed description of the population structure of K. aerogenes based on 97 publicly available genomes by using both, multilocus sequence typing and single nucleotide polymorphisms extracted from core genome. We also assessed virulence and resistance profiles using VFDB and CARD, respectively. We show that K. aerogenes has an open pangenome and a large effective population size, which account for its high genomic diversity and support that negative selection prevents fixation of most deleterious alleles. The population is structured in at least ten CCs, including two novel ones identified here, CC9 and CC10. The repertoires of resistance genes comprise a high number of antibiotic efflux proteins as well as narrow and extended spectrum {beta}-lactamases. Regarding the population structure, we identified two clusters based on virulence profile due to the presence of the toxin-encoding clb operon and the siderophore production genes, irp and ybt. Notably, CC3 comprises the majority of K. aerogenes isolates associated with hospital outbreaks, emphasizing the importance of its constant monitoring. Collectively, our results can be useful in the development of new therapeutic and surveillance strategies worldwide.

genomics↗