Publications by authors named "Gabriela Calegario"
Article Synopsis
- Mangroves in macro-tidal areas are crucial for carbon sequestration, but the role of their microbial communities in carbon and nutrient cycling is not fully understood.
- A study in the Amazon's extensive mangrove system showed that tidal influences significantly affect the composition and metabolism of microbial communities, especially in sulfur and nitrogen cycling.
- Findings indicated that specific microbial groups consistently drive carbon, nitrogen, and sulfur cycles across different spatial and temporal scales, highlighting the importance of tidal porewater exchange for these ecosystem processes.
Article Synopsis
- The Great Amazon Reef System (GARS) is a significant marine ecosystem located near the Amazon River, with rhodolith holobionts being key components in the area, which spans 56,000 km.
- Research aims to determine if environmental conditions like light, temperature, and depth affect the microbiomes of rhodoliths across different sectors (northern, central, southern) of GARS.
- Findings show that the microbiomes of rhodoliths are mostly similar across the study area but exhibit subtle differences, especially in the southern sector, where higher light leads to increased abundance of certain microbial groups and functional categories linked to photosynthesis and iron metabolism.
In the late Quaternary, glacial-interglacial transitions are marked by major environmental changes. Glacial periods in the western equatorial Atlantic (WEA) are characterized by high continental terrigenous input, which increases the proportion of terrestrial organic matter (e.g.
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- - The Campos Basin in southeastern Brazil is an area with active oil and gas activities, yet there is limited knowledge about its hydrocarbon content and microbial life in deep-sea sediments.
- - Researchers collected sediment samples from different locations around a seabed fissure to analyze taxonomic diversity and biogeochemical properties, discovering high levels of hydrocarbons and specific bacteria that can break down oil.
- - The study highlights the potential of using certain bacteria as biosensors to monitor sediment contamination and suggests that the impact of oil leakage on surrounding areas might be less significant than expected.
Plants produce a vast array of defense compounds to protect themselves from pathogen attack or herbivore predation. Saponins are a specific class of defense compounds comprising bioactive glycosides with a steroidal or triterpenoid aglycone backbone. The model legume synthesizes two types of saponins, hemolytic saponins and nonhemolytic soyasaponins, which accumulate as specific blends in different plant organs.
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- A649 is a novel bacterial species isolated from the healthy pufferfish Sphoeroides spengleri, classified as Enterovibrio baiacu sp nov.
- Genomic analysis shows A649 has significantly low amino acid/nucleotide identity (less than 95%) and genome similarity (less than 70%) compared to its closest relatives.
- The complete genome of strain A649 is approximately 5.4 million base pairs long and contains 4,826 coding genes, with unique features for distinguishing it from other Enterovibrio species.
Article Synopsis
- - The genome sequence of Shewanella corallii strain A687 was obtained from a pufferfish species called Sphoeroides spengleri.
- - This genetic assembly is made up of 5,215,037 base pairs and includes 284 separate fragments known as contigs.
- - The G+C content of the genome is 50.3%, which indicates the percentage of guanine and cytosine nucleotides in the DNA.
The genus encompasses seaweeds that are widely distributed throughout the world's oceans, with found along the tropical and subtropical coasts of the Western Atlantic. This wide distribution can lead to structured populations due to environmental differences (e.g.
View Article and Find Full Text PDFWe report here the novel species Halomonas coralii. The nearly complete genome of strain 362.1 consisted of 4.
View Article and Find Full Text PDFUnplanned oil spills during offshore oil production are a serious problem for the industry and the marine environment. Here we assess the biodegradation potential of marine microorganisms from three water depths in the Campos Basin (South Atlantic Ocean): (i) 5 m (surface), (ii) ∼80 m (chlorophyll maximum layer), and (iii) ∼1200 m (near the bottom). After incubating seawater samples with or without crude oil for 52 days, we used metagenomics and classic microbiology techniques to analyze microbial abundance and diversity, and measured physical-chemical parameters to better understand biodegradation processes.
View Article and Find Full Text PDFGenome Sequences of sp. nov. and sp. nov., Isolated from Rhodoliths.
Microbiol Resour Announc
November 2018
We report here the genome sequences of the novel isolates G62 and G98 from rhodoliths. The nearly complete genomes consisted of 4.7 Mbp (4,233 coding sequences [CDS]) for G62 and 4.
View Article and Find Full Text PDFThe red seaweed Laurencia dendroidea belongs to the Rhodophyta, a phylum of eukaryotic algae that is widely distributed across the oceans and that constitute an important source of bioactive specialized metabolites. Laurencia species have been studied since 1950 and were found to contain a plethora of specialized metabolites, mainly halogenated sesquiterpenes, diterpenes and triterpenes that possess a broad spectrum of pharmacological and ecological activities. The first committed step in the biosynthesis of triterpenes is the cyclization of 2,3-oxidosqualene, an enzymatic reaction carried out by oxidosqualene cyclases (OSCs), giving rise to a broad range of different compounds, such as the sterol precursors cycloartenol and lanosterol, or triterpene precursors such as cucurbitadienol and β-amyrin.
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