Publications by authors named "Gustavo B Gregoracci"
Vinasse is a by-product of sugarcane processing which is often used in fertigation; however, the direct use of vinasse harms the environment and reduces soil productivity due to its physicochemical properties. Anaerobic digestion (AD) offers an alternative to mitigate part of the negative effects. Anaerobic high-rate reactors, which mainly rely on sludge granulation, are mostly used in AD of vinasse wastewater.
View Article and Find Full Text PDFEffects of metal contamination with physicochemical properties on the sediment microbial communities in a tropical eutrophic-hypereutrophic urban reservoir in Brazil.
Gabrielle Maria Fonseca Pierangeli Karine Mirelle Rodrigues da Silva Lucia Helena Gomes Coelho Roseli Frederigi Benassi Mercia Regina Domingues Gustavo Bueno Gregoracci
Environ Sci Pollut Res Int
April 2023
Article Synopsis
- The study examined how metals like cadmium, copper, and chromium, along with physicochemical factors, influence microbial communities in the sediments of the Guarapiranga reservoir in Brazil.
- While metals had a minor impact individually, their effects were amplified when combined with sediment characteristics like carbon and sulfur levels, electrical conductivity, and water depth, which are influenced by human activities.
- Certain microbes, especially in metal-contaminated areas, may show resistance to metals and play roles in bioremediation, offering insights into how these communities can potentially help remove metals from polluted freshwater environments.
Spatial Variation and Environmental Parameters Affecting the Abundant and Rare Communities of Bacteria and Archaea in the Sediments of Tropical Urban Reservoirs.
Gabrielle Maria Fonseca Pierangeli Mercia Regina Domingues Rodrigo Brasil Choueri Werner Siegfried Hanisch Gustavo Bueno Gregoracci
Microb Ecol
July 2023
Article Synopsis
- Microbial communities in freshwater sediments are crucial for processing organic matter, affecting nutrient cycles and greenhouse gas emissions, and are influenced by environmental factors and human activities like pollution and damming.
- In a study of tropical urban reservoirs in Brazil, researchers found that the composition of bacterial and archaeal communities varied based on location and water quality, with abundant groups being specific genera from Bacteria and Archaea domains.
- The research identified that changes in microbial communities were driven by spatial variations and specific environmental conditions, highlighting the distinct impacts of pollution indicators such as phosphorus levels and water depth.
Corrigendum: Higher Abundance of Sediment Methanogens and Methanotrophs Do Not Predict the Atmospheric Methane and Carbon Dioxide Flows in Eutrophic Tropical Freshwater Reservoirs.
Gabrielle Maria Fonseca Pierangeli Mercia Regina Domingues Tatiane Araujo de Jesus Lúcia Helena Gomes Coelho Werner Siegfried Hanisch Gustavo Bueno Gregoracci
Front Microbiol
December 2021
Article Synopsis
- The text refers to a correction made to a scientific article previously published, identified by its DOI (Digital Object Identifier) 10.3389/fmicb.2021.647921.
- The correction likely addresses errors or clarifications needed in the original publication.
- Such corrections are important for maintaining the accuracy and credibility of scientific literature.
Article Synopsis
- The southwestern Atlantic rocky reefs are experiencing changes due to the invasion of sun-corals (Tubastraea tagusensis and T. coccinea), particularly at Búzios Island.
- Some colonies of T. tagusensis are showing signs of tissue necrosis, a condition not previously observed in this species or other similar corals.
- Research using next-generation sequencing revealed that corals with tissue necrosis have a more diverse microbiota compared to healthy colonies, allowing the identification of 21 potential pathogens associated with the disease.
Higher Abundance of Sediment Methanogens and Methanotrophs Do Not Predict the Atmospheric Methane and Carbon Dioxide Flows in Eutrophic Tropical Freshwater Reservoirs.
Gabrielle Maria Fonseca Pierangeli Mercia Regina Domingues Tatiane Araujo de Jesus Lúcia Helena Gomes Coelho Werner Siegfried Hanisch Gustavo Bueno Gregoracci
Front Microbiol
March 2021
Article Synopsis
- * The study examined the sediment microbiota in three urban tropical freshwater reservoirs and how different microorganisms influence the production and consumption of these gases across seasons.
- * Findings revealed that deeper waters harbor more methanogenic organisms, which are affected by pollution, while better sanitation reduces gas emissions, highlighting the need for improved wastewater management to combat climate change.
Article Synopsis
- Tubastraea tagusensis, or sun-coral, is an invasive coral species in the Southwestern Atlantic, spreading over 3500 km along Brazil's coast and causing significant ecological changes.* -
- Research using high throughput sequencing shows that its microbial community includes diverse bacterial groups, but the core microbiome of adult corals consists of only eight key genera, with some being passed from adults to larvae.* -
- The microbiome's composition remains consistent across different depths, highlighting that while some bacteria are inherited, others are acquired from the environment, potentially influencing the coral's adaptability and health.*
Article Synopsis
- - Advances in omics-based techniques have transformed our understanding of marine microorganisms, including archaea and bacteria, along with their viruses, by using genomics, metagenomics, and ecogenomics to study their ecology.
- - The review highlights three key areas: the unique roles of microbes in ecosystems, interactions between viruses and their hosts, and the relationships between microeukaryotes and other microorganisms.
- - The paper also touches on the discovery of new marine taxa, the need for a solid classification system for prokaryotes, progress in understanding cyanobacteria diversity, and improvements in ecological modeling, while also noting existing challenges and future research directions.
Article Synopsis
- - Marine sponges host complex microbial communities that may be responsible for producing secondary metabolites, like bromopyrrole alkaloids, which have notable biological activities.
- - Research on sponge species Agelas spp. and Tedania brasiliensis revealed distinct microbial halogenases, indicating a species-specific presence and a correlation between halogenase encoding bacteria abundance and bromopyrrole production.
- - The study suggests that sponges with numerous CRISPR sequences, like Agelas spp., may protect themselves from phage infections, while phages can facilitate the horizontal transfer of halogenases among holobionts, especially in more adaptable hosts like Tedania spp.
Article Synopsis
- The study focuses on the diversity and structure of virus assemblages in the Amazon River-ocean continuum, highlighting their importance in global carbon and nutrient cycling.
- Researchers collected viral DNA sequences from 12 locations along the river and plume, yielding 29,358 scaffolds and 15 new complete viral genomes, revealing distinct virome characteristics between the river and plume ecosystems.
- Findings indicate that bacteriophages were widespread, while eukaryotic viruses were more prevalent in the river; the study emphasizes the influence of water physical and chemical parameters, especially salinity, on viral distribution and contributes to understanding the role of viruses in the organic matter cycle.
Article Synopsis
- Marine viruses significantly influence host diversity, population dynamics, and biogeochemical cycling, contributing to the transfer of billions of tons of organic matter daily.
- A study presented a dataset of 27,346 marine virome contigs, including 44 complete genomes, surpassing the known marine phage genomes and revealing uncharacterized viral lineages.
- Utilizing a new host prediction method, researchers found that these viruses typically infect major marine microbiome members and identified patterns that demonstrate how these viral communities adapt to various environmental conditions in the oceans.
Article Synopsis
- Corals switch from autotrophic feeding during the day to heterotrophic feeding at night, creating different oxygen conditions that impact the microbial communities living around them.
- Most research on coral reef microbes has focused on daytime samples, leading to a potential bias in understanding these communities.
- The study analyzed microbial communities near the coral over a 48-hour cycle and found that microbial composition was stable between day and night, suggesting that water flow plays a bigger role than coral physiology in shaping these communities.
Article Synopsis
- Large rivers, like the Amazon, significantly disrupt reef distributions on tropical shelves by affecting salinity, pH, light penetration, and sedimentation over a large area of the North Atlantic.
- Despite these harsh conditions, a complex carbonate system thrives off the Amazon's mouth, characterized by unique hard-bottom structures, originating from sedimentation during low sea levels and continuing in certain areas.
- These carbonate structures support diverse marine life, including sponges and filter feeders, and act as a connectivity corridor for reef-associated species, offering insights into how tropical reefs can adapt to challenging conditions, which are becoming more common globally.
Article Synopsis
- - The study focuses on the transition between cold, nutrient-rich waters and warm, nutrient-poor waters in upwelling regions, examining the microbial and viral communities involved during this change.
- - By analyzing taxonomic, metabolic compositions, and physical-chemical data, researchers identified various metabolic processes and ecological interactions among planktonic microbes in both downwelling and upwelling states.
- - Key findings revealed that microbial activities such as nitrogen recycling and photosynthesis play significant roles in downwelling, while specific groups like diatoms and certain bacteria dominate upwelling, indicating their importance in the overall functioning of these ecosystems.
Article Synopsis
- Sponges host complex communities of microbes, and while their taxonomic makeup is known, understanding their functional roles in symbiosis is a key challenge.
- Researchers analyzed the microbiota of two sponge species, Didiscus oxeata and Scopalina ruetzleri, from the St Peter and St Paul archipelago using metagenomics.
- Findings revealed that while both sponge communities share core functions, they differ in microbial composition, diversity, and metabolic strategies, particularly in how they process carbon, nitrogen, and sulfur.
Article Synopsis
- - The draft genome sequences of Lactococcus lactis subsp. lactis CECT 4433, a strain used for cheese fermentation, have been presented.
- - This research enhances our understanding of genetic variation and complexity within this bacterial genus, which is important for fermentation processes.
- - It also offers insights into the evolutionary aspects of these bacteria, helping to map out their development and diversity.
Article Synopsis
- - The study investigates how cholesterol depletion affects gene expression in myoblasts, focusing on the process of skeletal muscle differentiation and its relationship with the Wnt/beta-catenin signaling pathway.
- - Using methyl-β-cyclodextrin (MbCD) to extract cholesterol from chick skeletal muscle cells, researchers analyzed transcriptome changes, revealing significant alterations in genes associated with key cellular functions.
- - Findings indicate that cholesterol availability in plasma membranes influences gene transcription related to processes like apoptosis, cell cycle regulation, and cytoskeletal organization, enhancing our understanding of muscle differentiation.
Article Synopsis
- Salinivibrios are halophilic bacteria found in high-salt environments, with three new strains closely linked to S. costicola discovered in Socompa Lake, a hypersaline lake in the Andes.
- These new strains showed extreme resistance to arsenic, high salt concentrations, and UV-B radiation, supported by phenotypic testing and genomic analysis.
- The presence of specific resistance genes and adaptations for energy production suggests that these novel Salinivibrios have unique traits that enable them to survive in challenging conditions at Socompa Lake.
Article Synopsis
- Rhodoliths are crucial coralline algae that create extensive beds in marine environments, acting as habitats for organisms and contributing significantly to calcium carbonate production, particularly in the Abrolhos Bank, Brazil.
- Despite their ecological importance, little is known about the microbial diversity and interactions within rhodoliths, prompting a detailed study on their microbiome and functions.
- The research found a unique microbiome in rhodoliths that enhances biomineralization, with high photosynthesis rates generating substantial carbon production, highlighting their role in the South Atlantic Ocean's ecosystem.
Article Synopsis
- Coral health is declining globally due to various stressors, with white plague disease (WP) posing a significant threat to the native coral species Mussismilia braziliensis in Brazil's Abrolhos Bank.
- Researchers conducted a metagenomic analysis to identify the microbial communities associated with healthy and WP-affected corals and developed a protocol for extracting DNA from coral tissues.
- Their findings showed a variety of microbes present in both healthy and diseased corals, with specific groups like Vibrionales and eukaryotic sequences (Alveolata, Apicomplexa) being more prevalent in WP-affected corals, indicating that WP disease may arise from a combination of multiple microbial factors.
Article Synopsis
- The study focuses on the red seaweed Laurencia dendroidea, which is known for producing important secondary metabolites, particularly halogenated compounds with potential pharmacological properties.
- Researchers conducted a transcriptomic analysis to uncover the genes associated with terpenoid biosynthesis in L. dendroidea and explored its interactions with the surrounding microbial community.
- Findings highlighted that bacteria, especially nitrogen-fixing Cyanobacteria and aerobic heterotrophic Proteobacteria, were the dominant group in its microbiome, while eukaryotic transcripts were linked to processes like photosynthesis and defense mechanisms, contributing to insights about the seaweed's ecological and chemical roles.
Article Synopsis
- The study investigates how physical, chemical, and biological factors affect the diversity and abundance of bacterioplankton in Guanabara Bay, Brazil, especially comparing inner bay areas with higher nutrient levels to outer areas with lower levels.
- Inner bay areas showed increased microbial growth, particularly of Gammaproteobacteria, while areas with less nutrients favored Alphaproteobacteria and Flavobacteria.
- Metagenomic analysis suggested that phosphorus limitation plays a significant role in shaping bacterial communities, impacting both the overall diversity and the specific abundance of vibrio populations.
Gestational malaria associated to Plasmodium vivax and Plasmodium falciparum placental mixed-infection followed by foetal loss: a case report from an unstable transmission area in Brazil.
Bruna O Carvalho Joycenéa S Matsuda Sergio L B Luz Flor E Martinez-Espinosa Juliana A Leite Gustavo B Gregoracci
Malar J
June 2011
Article Synopsis
- - Gestational malaria, which affects both mothers and their babies, was reported in a case from Manaus, Brazil, involving a mixed infection of Plasmodium vivax and Plasmodium falciparum that led to fetal loss.
- - Despite the hospitals seeing more cases of Plasmodium vivax, the mortality rate remains low, and in this case, P. falciparum was not detected in the patient's blood, suggesting its effects were masked by the presence of P. vivax.
- - The findings highlight how different malaria parasites can interact, influencing disease outcomes and raising important questions about diagnostics, treatment during pregnancy, and prenatal care in regions with unstable malaria transmission like the Brazilian Amazon.
Article Synopsis
- - The study aimed to identify and characterize lactobacillus species found in the vaginal contents of healthy women, focusing on their prevalence and phenotypic traits.
- - Researchers isolated lactobacillus from 135 women with no vaginal infections and used techniques like multiplex PCR and gene sequencing to identify the strains; they found four main species: L. crispatus, L. jensenii, L. gasseri, and L. vaginalis.
- - The results indicated that the prevalent species produced H2O2 and exhibited varying adhesion to epithelial cells, suggesting their potential role in maintaining vaginal health.
Article Synopsis
- Prokaryotes benefit from a fluid genome that allows them to rapidly adapt to different environments and selective pressures.
- Lateral gene transfer (LGT), involving mechanisms like transformation, conjugation, and transduction, plays a key role in these genetic changes.
- Recent genome sequencing of Choromobacterium violaceum revealed genetic exchanges with other bacterial species, suggesting LGT is crucial for developing new traits in this bacterium.