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Nunes da Rocha, U.

Publications and source records attributed to Nunes da Rocha, U..

13 recordsLinked to original sources

BioAutoML-FAST: an automated machine-learning platform for reusable and benchmarked biological sequence models

The prediction of biological sequence properties has traditionally relied on alignment-based methods that assume evolutionary homology and depend on curated reference databases. This, in turn, limits scalability and sensitivity for large or heterogeneous datasets, remote homologs, short sequences, and rapidly evolving genomic regions. Although Machine-Learning (ML) approaches offer alignment-free alternatives, their broader adoption is limited by: (i) the lack of standardized, externally validated benchmark models across diverse datasets, and (ii) the technical expertise required for feature engineering, model selection, and evaluation. Automated machine learning (AutoML) alleviates these challenges by systematically optimizing representations and models with minimal user intervention. However, most existing frameworks prioritize task-specific model construction and lack mechanisms for preserving trained models as persistent, comparable benchmarks. We introduce BioAutoML-FAST, an end-to-end web platform for automated ML analysis of nucleotide and amino acid sequences. It supports both classification and regression tasks and automates feature extraction, model training, and evaluation without requiring prior user expertise. Uniquely, it serves as a community benchmarking resource, hosting a continuously expanding repository of reusable, standardized models (currently 60) for genomic, transcriptomic, and proteomic applications. Extensive validation on independent datasets demonstrates performance comparable to or exceeding that of state-of-the-art methods, including protein language models such as ESM-2. BioAutoMLFAST is available at https://bioautoml.icmc.usp.br/. This website is free and open to all users, and there is no login requirement.

bioinformatics↗

BioPrediction-PPI: Simplifying the Prediction of Protein-Protein Interactions through Artificial Intelligence

Proteins are essential in biological processes, primarily through their interactions with other molecules, including proteins. These interactions are crucial for cellular functions and maintaining life. Predicting Protein-Protein Interactions (PPIs) is very important, although challenging, for understanding cellular functions and diseases. This paper presents BioPrediction-PPI, a new end-to-end Machine Learning (ML) framework for PPI prediction, automating the entire process from feature extraction to interpretability, with no manual intervention required. BioPrediction-PPI stands as one of the few end-to-end models that do not rely on deep learning, enabling the automated use of trained models on new data. It offers interpretability graphs for creating auditable models and has been evaluated through comparative experiments with 30 previous studies, using 15 datasets. Additionally, the interpretability graphs offer valuable insights for model evaluation and experimental design, facilitating informed decision-making. BioPrediction-PPI demonstrates competitive performance across multiple datasets, even without the use of deep learning, and is a transparent, white-box model that can be easily used by biologists and practitioners without a background in computer science. The proposed framework has the potential to accelerate research in biology and related fields by making AI-driven tools more accessible.

bioinformatics↗

Simulation of 69 microbial communities indicates sequencing depth and false positives are major drivers of bias in Prokaryotic metagenome-assembled genome recovery

We hypothesize that sample evenness, sequencing depth and taxonomic relatedness influence the recovery of metagenome-assembled genomes (MAGs). To test this hypothesis, we assessed MAG recovery in three in silico microbial communities composed of 42 species with the same richness but different sample evenness, sequencing depth and taxonomic distribution profiles using three different pipelines for MAG recovery. The pipeline developed by Parks and colleagues (8K) generated the highest number of MAGs and the lowest number of true positives per community profile. The pipeline by Karst and colleagues (DT) showed the most accurate results ([~] 92%), outperforming the 8K and Multi-Metagenome pipeline (MM) developed by Albertsen and collaborators. Sequencing depth influenced the accurate recovery of genomes when using the 8K and MM, even with contrasting patterns: the MM pipeline recovered more MAGs found in the original communities when employing sequencing depths up to 60 million reads, whilst the 8K recovered more true positives in communities sequenced above 60 million reads. DT showed the best species recovery from the same genus, even though close-related species have a low recovery rate in all pipelines. Our results highlight that more bins do not translate to the actual community composition and that sequencing depth plays a role in MAG recovery and increased community resolution. Even low MAG recovery error rates can significantly impact biological inferences. Our data indicates the scientific community should their findings from MAG recovery, especially when asserting novel species or metabolic traits.

bioinformatics↗

Functional redundancy secures resilience of chain elongation communities upon pH shifts in closed bioreactor ecosystems

For anaerobic mixed cultures performing microbial chain elongation, it is unclear how pH alterations affect the abundance of key players, microbial interactions and community functioning in terms of medium-chain carboxylate yields. We explored pH effects on mixed cultures enriched in continuous anaerobic bioreactors representing closed model ecosystems. Increasing the pH from 5.5 to 6.0 caused fluctuations in community composition and yields of n-butyrate, n-caproate and n-caprylate. Further pH increase to 6.5 restored previous yield values while the community entered a new state characterized by lower diversity and evenness but apparently higher richness, indicating the presence of species below the detection threshold in the previous state. We applied Aitchison PCA clustering, linear mixed-effects models and random forest classification on our datasets. Different pH preferences of two key chain elongation species - one Clostridium IV species related to Ruminococcaceae bacterium CPB6, and one Clostridium sensu stricto species related to Clostridium luticellarii - were determined. Based on relative abundances measured by 16S rRNA amplicon sequencing, network analysis revealed positive correlations of Clostridium IV with lactic acid bacteria, which switched from Olsenella to Lactobacillus along the pH increase, illustrating the plasticity of the food web in chain elongation communities. The pH increase induced dramatic shifts in community composition whereas process performance (in terms of product range and yields) returned to the previous state. Despite long-term cultivation in closed systems over the pH shift experiment, the communities retained functional redundancy in fermentation pathways, reflected by the emergence of rare species and concomitant recovery of chain elongation functions.

microbiology↗

MuDoGeR: Multi-Domain Genome Recovery from metagenomes made easy

Several computational frameworks and workflows that recover genomes from prokaryotes, eukaryotes, and viruses from metagenomes exist. However, it is difficult for scientists with little bioinformatics experience to evaluate quality, annotate genes, dereplicate, assign taxonomy and calculate relative abundance and coverage of genomes belonging to different domains. MuDoGeR is a user-friendly tool accessible for non-bioinformaticians that make it easy to recover genomes of prokaryotes, eukaryotes, and viruses from metagenomes, either alone or in combination. We tested MuDoGer using 24 individual-isolated genomes and 574 metagenomes, demonstrating the applicability for a few samples and high throughput. MuDoGeR is open-source software available at https://github.com/mdsufz/MuDoGeR.

bioinformatics↗

Recovery of 447 Eukaryotic bins reveals major challenges for Eukaryote genome reconstruction from metagenomes.

An estimated 8.7 million eukaryotic species exist on our planet. However, recent tools for taxonomic classification of eukaryotes only dispose of 734 reference genomes. As most Eukaryotic genomes are yet to be sequenced, the mechanisms underlying their contribution to different ecosystem processes remain untapped. Although approaches to recover Prokaryotic genomes have become common in genome biology, few studies have tackled the recovery of Eukaryotic genomes from metagenomes. This study assessed the reconstruction of Eukaryotic genomes using 215 metagenomes from diverse environments using the EukRep pipeline. We obtained 447 eukaryotic bins from 15 classes (e.g., Saccharomycetes, Sordariomycetes, and Mamiellophyceae) and 16 orders (e.g., Mamiellales, Saccharomycetales, and Hypocreales). More than 73% of the obtained eukaryotic bins were recovered from samples whose biomes were classified as host-associated, aquatic and anthropogenic terrestrial. However, only 93 bins showed taxonomic classification to (9 unique) genera and 17 bins to (6 unique) species. A total of 193 bins contained completeness and contamination measures. Average completeness and contamination were 44.64% ({sigma}=27.41%) and 3.97% ({sigma}=6.53%), respectively. Micromonas commoda was the most frequent taxa found while Saccharomyces cerevisiae presented the highest completeness, possibly resulting from a more significant number of reference genomes. However, mapping eukaryotic bins to the chromosomes of the reference genomes suggests that completeness measures should consider both single-copy genes and chromosome coverage. Recovering eukaryotic genomes will benefit significantly from long-read sequencing, intron removal after assembly, and improved reference genomes databases.

bioinformatics↗

Stabilising microbial communities by looped mass transfer

Creating structurally and functionally stable microbiomes would be greatly beneficial to biotechnology and human health but so far has proven challenging. Here, we propose a looped mass transfer design that keeps microbiomes constant over long periods of time. The effluent of five parallel reactors that began with the same inoculum, was mixed in a reactor that represented a regional pool. Part of this pool was transferred back to the five reactors. Community dynamics were monitored and visualized by quantitative microbial flow cytometry and selected taxonomic sequencing of whole communities and sorted subcommunities. The rescue effect, known from metacommunity theory, was the main stabilizing mechanism that led to the survival of subcommunities with zero netgrowth, especially at high mass transfer rates. The looped mass transfer approach promises to overcome notorious stochastic structural fluctuations in bioreactors and has the potential to design and stabilize communities that can perform desired functions.

microbiology↗

OrtSuite - from genomes to prediction of microbial interactions within targeted ecosystem processes

The high complexity found in microbial communities makes the identification of microbial interactions challenging. To address this challenge, we present OrtSuite, a flexible workflow to predict putative microbial interactions based on genomic content of microbial communities and targeted to specific ecosystem processes. The pipeline is composed of three user-friendly bash commands. OrtSuite combines ortholog clustering with genome annotation strategies limited to user-defined sets of functions allowing for hypothesis-driven data analysis such as assessing microbial interactions in specific ecosystems. OrtSuite matched, on average, 96 % of experimentally verified KEGG orthologs involved in benzoate degradation in a known group of benzoate degraders. Identification of putative synergistic species interactions was evaluated using the sequenced genomes of an independent study which had previously proposed potential species interactions in benzoate degradation. OrtSuite is an easy to use workflow that allows for rapid functional annotation based on a user curated database and can easily be extended to ecosystem processes where connections between genes and reactions are known. OrtSuite is an open-source software available at https://github.com/mdsufz/OrtSuite.

bioinformatics↗

PredicTF: a tool to predict bacterial transcription factors in complex microbial communities.

Transcription Factors (TFs) are proteins that control the flow of genetic information by regulating cellular gene expression. Here we describe PredicTF, a first platform supporting the prediction and classification of novel bacterial TF in complex microbial communities. We evaluated PredicTF using a two-step approach. First, we tested PredictTFs ability to predict TFs for the genome of an environmental isolate. In the second evaluation step, PredicTF was used to predict TFs in a metagenome and 11 metatranscriptomes recovered from a community performing anaerobic ammonium oxidation (anammox) in a bioreactor. PredicTF is open source pipeline available at https://github.com/mdsufz/PredicTF.

bioinformatics↗

Community RNA-Seq: Multi-kingdom responses to living versus decaying root inputs in soil

Roots are the primary source of organic carbon inputs to most soils. Decomposition is a multi-trophic process involving multiple kingdoms of microbial life, but typically microbial ecology studies focus on one or two major lineages in isolation. We used Illumina shotgun RNA sequencing to conduct PCR-independent SSU rRNA community analysis ("community RNA-Seq") to simultaneously study the bacteria, archaea, fungi, and microfauna surrounding both living and decomposing roots of the annual grass, Avena fatua. Plants were grown in 13CO2-labeled microcosms amended with 15N-root litter. We identified rhizosphere substrate preferences for 13C-exudates versus 15N-litter using NanoSIMS microarray imaging (Chip-SIP). When litter was available, rhizosphere and bulk soil had significantly more Amoebozoa, which are potentially important yet often overlooked top-down drivers of detritusphere community dynamics and nutrient cycling. Bulk soil containing litter was depleted in Actinobacteria but had significantly more Bacteroidetes and Proteobacteria. While Actinobacteria were abundant in the rhizosphere, Chip-SIP showed Actinobacteria preferentially incorporated litter relative to root exudates, indicating this groups more prominent role in detritus elemental cycling in the rhizosphere. Our results emphasize that decomposition is a multi-trophic process involving cross-kingdom interactions, and the trajectory of carbon through this soil food web likely impacts the fate of carbon in soil.

microbiology↗

Biodiversity and niche partitioning in an anaerobic benzene degrading culture

A key question in microbial ecology is what the driving forces behind the persistence of large biodiversity in natural environments are. We studied a microbial community with more than 100 different types of species which evolved in a 15-years old bioreactor with benzene as the main carbon and free energy source and nitrate as the electron acceptor. We demonstrate that only a few community members are able to degrade benzene, and that most of the others feed on the metabolic left-overs or on the contents of dead cells making up a food web with different trophic levels. As a result of niche partitioning, a high species richness is maintained and the complexity of a natural community is stabilized in a relatively simple environment. This view highlights the importance of species interactions and interdependencies, which drive microbial community structure and function. These mechanisms may well be conserved across ecosystems.

ecology↗

Potential soil transmission of a novel Candidatus Liberibacter strain detected in citrus seedlings grown in soil from a huanglongbing infested citrus grove

Candidatus Liberibacter spp. are Alphaproteobacteria associated with plants and psyllid vectors. Most cause plant diseases, including Ca Liberibacter asiaticus (Las) associated with citrus huanglongbing (HLB). Replacing HLB-infected by Las-free citrus trees results in fast re-infection despite psyllid control. To check if HLB could be soil-borne, we performed an insect-free greenhouse-experiment with 130 mandarin seedlings in two citrus-grove soils (A and B), non-autoclaved or autoclaved. Liberibacter-specific 16S-rDNA PCR primers to detect Las were used to search for Ca. Liberibacter spp. in mandarin leaves. Seven plants grown in non-autoclaved soil B showed HLB-like symptoms and tested positive after 2.5 and 8.5 months using three different primer systems: two based on the 16S-rDNA gene (primers HLBas/HLBr and OI2c/OI1) and one based on the rplA/rplJ gene (primers LAA2/LAJ5). DNA segments from these plants amplified by primers OI2c/OI1 were cloned and sequenced; they were 95.9 % similar to Las and 94.8% to Ca. Liberibacter africanus (Laf). The DNA product from Liberibacter-group specific PCR primers for the rplA/rplJ gene was 87.6% similar to that of Las and 78.2% of Laf. As the strain obtained originated from soil and was different from existing Ca. Liberibacter species, this strain may be a new species.

ecology↗

TerrestrialMetagenomeDB: a public repository of curated and standardized metadata for terrestrial metagenomes

Microbiome studies focused on the genetic potential of microbial communities (metagenomics) became standard within microbial ecology. MG-RAST and the Sequence Read Archive (SRA), the two main metagenome repositories, contain over 202 858 public available metagenomes and this number has increased exponentially. However, mining databases can be challenging due to misannotated, misleading and decentralized data. The main goal of TerrestrialMetagenomeDB is to make it easier for scientists to find terrestrial metagenomes of interest that could be compared with novel datasets in meta-analyses. We defined terrestrial metagenomes as those that do not belong to marine environments. Further, we curated the database using text mining to assign potential descriptive keywords that better contextualize environmental aspects of terrestrial metagenomes, such as biomes and materials. TerrestrialMetagenomeDB release 1.0 includes 15 194 terrestrial metagenomes from SRA and MG-RAST. Together, the downloadable data amounts to 68 Tbp. In total, 199 terrestrial terms were divided into 14 categories. These metagenomes span 84 countries, 31 biomes and 7 main source materials. The TerrestrialMetagenomeDB is publicly available at https://webapp.ufz.de/tmdb.

bioinformatics↗