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The scleractinian reef building coral Madracis decactis is a cosmopolitan species. Understanding host–symbiont associations is critical for assessing coral’s habitat requirements and its response to environmental changes. In this study, we performed a fine grained phylogenetic analyses of Symbiodiniaceae associated with Madracis in two locations in the Southwest Atlantic Ocean (Abrolhos Bank and St. Peter and St. Paul Archipelago). Previous studies have argued that Madracis is a specialist coral, with colonies harboring a single symbiont from the genus Breviolum (formerly clade B). However, these previous studies have not precisely addressed if Madracis is colonized by several types of Symbiodiniaceae simultaneously or whether this coral is a specialist. The hypothesis that Madracis is a generalist coral host was evaluated in the present study. A total of 1.9 million reads of ITS2 nuclear ribosomal DNA were obtained by Illumina MiSeq sequencing. While Symbiodiniaceae ITS2 sequences between two sampling depths were almost entirely (62%) from the genus Breviolum (formerly clade B), shallow (10–15 m) populations in Abrolhos had a greater diversity of ITS2 sequences in comparison to deeper (25–35 m) populations of St. Peter and St. Paul Archipelago. Cladocopium (formerly clade C) and Symbiodinium (formerly clade A) were also found in Abrolhos. A single Madracis colony can host different symbiont types with > 30 Symbiodiniaceae ITS2-type profiles. Abrolhos corals presented a higher photosynthetic potential as a possible result of co-occurrence of multiple Symbiodiniaceae in a single coral colony. Multiple genera/clades of Symbiodiniaceae possibly confer coral hosts with broader environmental tolerance and ability to occupy diverse or changing habitats.

Vibrio fluvialis is a halophilic bacterium frequently found in estuarine and coastal waters environments. The strain 362.3 was isolated from Mussismilia braziliensis coral of Abrolhos Bank. In this study, to gain insights into the marine adaptation in V. fluvialis, we sequenced the genome of 362.3 strain, which comprised 4,607,294 bp with a G + C content of 50.2%. In silico analysis showed that V. fluvialis 362.2 encodes genes related to chitin catabolic pathway, iron metabolism, osmotic stress and membrane transport.

Aquimarina litoralis CCMR20 originated from the coral Mussismilia braziliensis (Sebastiao Gomes Reef, Brazil, summer 2010). To gain new insights into the genomic repertoire associated with symbioses, we obtained the genome sequence of this strains using Illumina sequencing. CCMR20 has a genome size of 6.3 Mb, 32.6%GC, and 5513 genes (37 tRNA and 4 rRNA). A more fine-grained examination of the gene repertoire of CCMR20 disclosed genes engaged with symbiosis (heterotrophic carbon metabolism, CAZymes, B-vitamins group, carotenoid pigment and antioxidant molecules production). Genomic evidence further expand the possible relevance of this symbiont in the health of Mussismilia holobiont.Whole Genome Shotgun project has been deposited at DDBJ/ENA/GeneBank under the accession number WEKL00000000.

Pigmented bacterial symbionts play major roles in the health of coral holobionts. However, there is scarce knowledge on the diversity of these microbes for several coral species. To gain further insights into holobiont health, pigmented bacterial isolates of Fabibacter pacificus (Bacteroidetes; n = 4), Paracoccus marcusii (Alphaproteobacteria; n = 1), and Pseudoalteromonas shioyasakiensis (Gammaproteobacteria; n = 1) were obtained from the corals Mussismilia braziliensis and Montastraea cavernosa in Abrolhos Bank, Brazil. Cultures of these bacterial symbionts produced strong antioxidant activity (catalase, peroxidase, and oxidase). To explore these bacterial isolates further, we identified their major pigments by HPLC and mass spectrometry. The six phylogenetically diverse symbionts had similar pigment patterns and produced myxol and keto-carotene. In addition, similar carotenoid gene clusters were confirmed in the whole genome sequences of these symbionts, which reinforce their antioxidant potential. This study highlights the possible roles of bacterial symbionts in Montastraea and Mussismilia holobionts.

Bacteria associated with Symbiodinium may exert relevant roles in the Symbiodinium and the coral host. The bacterial isolate Ep20 was obtained from cell suspensions of Symbiodinium retrieved from the endemic coral Mussismilia braziliensis (Abrolhos Bank, Brazil). Here we aimed to analyze the genomic repertoire of Ep20 to gain insights into its possible roles in the coral holobiont. Ep20 enhanced the growth of Symbiodinium under controlled laboratory conditions, possibly through nitrogen fixation and vitamin production. The genome of Ep20 contains 5.5 Mbp (65% G + C content), 5397 genes, 53 tRNAs, and four rRNAs. Ep20 was identified as Mameliella alba, a member of the Roseobacter Clade Bacteria (RCB, Alphaproteobacteria). The genomic repertoire of Ep20 includes genes responsible for i. Aerobic Anoxygenic Photosynthesis (AAP), ii. Cofactors and vitamins (B12), iii. Gene Transfer Agents (GTAs), iv. Dimethylsulfoniopropionate (DMSP) metabolism, v. Carbon and Nitrogen fixation, and vi. Secondary metabolites (e.g., Terpenes). The genomic attributes of Ep20 hint at a possible mutualistic interaction with Symbiodinium, both in the free-living and in the coral holobiont lifestyles.

The Guandu River, one of the main rivers in the state of Rio de Janeiro, provides water for more than nine million people in the metropolitan region. However, the Guandu has suffered from massive domestic and industrial pollution for more than two decades, leading to high levels of dissolved total phosphorus, cyanobacteria, and enteric bacteria observed during the summers of 2020 and 2021. The use of Phoslock, a palliative compound, was not effective in mitigating the levels of phosphorus in the Guandu River. Furthermore, potable water driven from the river had levels of 2-MIB/geosmin and a mud smell/taste. With all these problems, several solutions are proposed for improving the Guandu River water quality, including establishment of (i) sewage treatment plants (STPs), (ii) strict water quality monitoring, (iii) environmental recovery (e.g., reforestation), and (iv) permanent protected areas. The objective of this paper is to verify the poor water quality in the Guandu and the ineffectiveness and undesired effects of Phoslock.

The scleractinian reef building coral Madracis decactis is a cosmopolitan species. Understanding host–symbiont associations is critical for assessing the coral’s habitat occupancy and it’s response to environmental changes. In this study, we performed fine grained phylogenetic analyzes of Symbiodiniaceae algae associated with Madracis across a broad latitudinal gradient in the SW Atlantic (Abrolhos Bank, and St. Peter and St. Paul Archipelago). Previous studies have argued that Madracis is a specialist coral, with colonies harboring a single symbiont type B. However, these previous studies have not precisely addressed if Madracis is colonized by several types of Symbiodiniaceae simultaneously, or if whether this coral is a specialist. The hypothesis that Madracis is a generalist coral host was evaluated in the present study. A total of 1.9 million reads of ITS2 nuclear ribosomal DNA were obtained by Illumina MiSeq sequencing. ITS2 sequences were classified into Clades A, B, and C in Abrolhos, and only clade B symbionts recorded in St. Peter and St. Paul. This study also demonstrate that a single Madracis colony can host different symbiont types with >30 Symbiodiniaceae species. Abrolhos corals presented a higher photosynthetic potential as a possible result of co-occurrence of multiple Symbiodiniaceae in a single coral colony. Multiple clades of Symbiodiniaceae possibly confer coral hosts with broader environmental tolerance and ability to occupy diverse or changing habitats.

The Great Amazon Reef System (GARS) covers an estimated area of 56,000 km2 off the mouth of the Amazon River. Living rhodolith holobionts are major benthic components of the GARS. However, it is unclear whether environmental conditions modulate the rhodolith microbiomes. Previous studies suggest that environmental parameters such as light, temperature, depth, and nutrients are drivers of rhodolith health. However, it is unclear whether rhodoliths from different sectors (northern, central, and southern) from the GARS have different microbiomes. We analysed metagenomes of rhodoliths (n = 10) and seawater (n = 6), obtained from the three sectors, by illumina shotgun sequencing (total read counts: 25.73 million). Suspended particulate material and isotopic composition of dissolved organic carbon (δ13C) indicated a strong influence of the Amazon river plume over the entire study area. However, photosynthetically active radiation at the bottom (PARb) was higher in the southern sector reefs, ranging from 10.1 to 14.3 E.m−2 day−1. The coralline calcareous red algae (CCA) Corallina caespitosa, Corallina officinalis, Lithophyllum cabiochiae, and Hapalidiales were present in the three sectors and in most rhodolith samples. Rhodolith microbiomes were very homogeneous across the studied area and differed significantly from seawater microbiomes. However, some subtle differences were found when comparing the rhodolith microbiomes from the northern and central sectors to the ones from the southern. Consistent with the higher light availability, two phyla were more abundant in rhodolith microbiomes from southern sites (Bacteroidetes, and Cyanobacteria). In addition, two functional categories were enhanced in southern rhodolith microbiomes (iron acquisition and metabolism, and photosynthesis). Phycobiliprotein-coding genes were also more abundant in southern locations, while the functional categories of respiration and sulfur metabolism were enhanced in northern and central rhodolith microbiomes, consistent with higher nutrient loads. The results confirm the conserved nature of rhodolith microbiomes even under pronounced environmental gradients. Subtle taxonomic and functional differences observed in rhodolith microbiomes may enable rhodoliths to thrive in changing environmental conditions.

Description of a Gram-negative, motile, circular-shaped bacterial strain, designated A511

Vibrio fluvialis is a halophilic bacterium frequently found in estuarine and coastal waters environments. The strain 362.3 was isolated from Mussismilia braziliensis coral of Abrolhos Bank. In this study, to gain insights into the marine adaptation in V. fluvialis, we sequenced the genome of 362.3 strain, which comprised 4,607,294 bp with a G + C content of 50.2%. In silico analysis showed that V. fluvialis 362.2 encodes genes related to chitin catabolic pathway, iron metabolism, osmotic stress and membrane transport.

Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) is a rapid, cost-effective and high-throughput method for bacteria characterization. However, most previous studies focused on clinical isolates. In this study, we evaluated the use of MALDI-TOF MS as a rapid screening tool for marine bacterial symbionts. A set of 255 isolates from different marine sources (corals, sponge, fish and seawater) was analyzed using cell lysates to obtain a rapid grouping. Cluster analysis of mass spectra and 16S rRNA showed 18 groups, including Vibrio, Bacillus, Pseudovibrio, Alteromonas and Ruegeria. MALDI-TOF distance similarity scores ≥ 60% and ≥ 70% correspond to ≥ 98.7% 16S rRNA gene sequence similarity and ≥ 95% pyrH gene sequence similarity, respectively. MALDI-TOF MS is a useful tool for Vibrio species groups’ identification.

We present here the genome sequence of Shewanella corallii strain A687 isolated from pufferfish Sphoeroides spengleri (Family Tetraodontidae). The assembly consists of 5,215,037 bp and contains 284 contigs, with a G+C content of 50.3%.

Description of a Gram-negative, motile, circular-shaped bacterial strain, designated A511T obtained from the skin of the pufferfish Sphoeroides spengleri (Family Tetraodontidae), collected in Arraial do Cabo, Brazil. Optimum growth occurs at 20–28 °C in the presence of 3% NaCl. The genome sequence of the novel isolate consisted of 4.36 Mb, 3,976 coding genes and G + C content of 42.5%. Genomic taxonomy analyses based on average amino acid (AAI), genome-to-genome-distance (GGDH) and phylogenetic reconstruction placed A511T (= CBAS 712T = CAIM 1939T) into a new species of the genus Vibrio (Vibrio tetraodonis sp. nov.). The genome of the novel species contains eight genes clusters (~ 183.9 Kbp in total) coding for different types of bioactive compounds that hint to several possible ecological roles in the pufferfish host.

We report here the novel species Halomonas coralii. The nearly complete genome of strain 362.1T consisted of 4.4 Mbp (3989 CDS; 66.3% GC). Genomic taxonomy analysis demonstrates that the novel strain has

On November 5th, 2015, the Fundao dam rupture released >50 million m3 of ore tailings into the Doce River, Minas Gerais State, Brazil. The huge volume of mud spread along the river and reached the sea, 17 days after the disaster, in Regencia, Espirito Santo State (ES). In 2018, after three years of the disaster, the impacts of the ore tailings in the marine environment are still unclear. This study aims to investigate possible short-term impacts in marine biodiversity caused by the ore tailings' mud over the reef ecosystems that are closest to the disaster area: i.e. recently discovered reefs in the southern Abrolhos Bank. A remote sensing surveillance including winds, sea surface temperature, total suspended material and watercolor (MODIS Aqua data) indicated that the iron tailings plume reached the southern portion of Abrolhos Bank on June 16th, 2016. Subsequently, to obtain further evidence of the presence of the tailings in the coral reefs, water samples were collected in a gradient spanning from the river estuary to the reefs in southern Abrolhos Bank, we also analyzed the isotopic and microbial composition of the samples, as well as the reef benthic composition. Despite no clues of negative impact on benthic (coral) communities, isotopic analysis confirmed the presence of the plume over the reefs area. This study serves as a baseline for future long-term impact assessments of the health of coral reefs in the Abrolhos Bank.

The genus Plocamium encompasses seaweeds that are widely distributed throughout the world’s oceans, with Plocamium brasiliense 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., light levels or temperature), restricted gene flow, and the presence of cryptic species. Abiotic variation can also affect gene expression, which consequently leads to differences in the seaweeds protein profile. This study aimed to analyze the genetic and proteomic profiles of P. brasiliense sampled in two geographically distinct sites on the coastline of Rio de Janeiro state, Brazil: Arraial do Cabo (P1) and Búzios (P2). The genetic profiles of macroalgal specimens from these two sites were indistinguishable as assessed by the markers UPA/23S, rbcL, and COI-5P; however, the protein profiles varied significantly between populations from the two sites. At both sites the ribulose-1,5-biphosphate carboxylase/oxygenase was the most abundant protein found in P. brasiliense specimens. The number of phycobiliproteins differed between both sites with the highest numbers being found at P1, possibly due to water depth. The differences in proteomic profiles of the two nearly identical populations of P. brasiliense suggest that environmental parameters such as light availability and desiccation might induce distinct protein expression, probably as a result of the phenotypic plasticity within this population of seaweed.

We report here the genome sequences of the novel isolates G62 T and G98 T from rhodoliths. The nearly complete genomes consisted of 4.7 Mbp (4,233 coding sequences [CDS]) for G62 T and 4.5 Mbp (4,085 CDS) for G98 T .

The nutrient and oxygen gradient present in marine sediments promotes high levels of microbial diversity. We applied metagenomics and biogeochemical tools to analyze microbial communities in different sediment depths (0–4 m below sea floor, mbsf) from Guanabara Bay, Brazil, a brackish tropical ecosystem with a history of massive anthropogenic impacts, and a largely unknown sediment microbial diversity. Methanogens (e.g. Methanosarcinales, Methanomicrobiales) were more abundant at 1 mbsf, while sulphate-reducing microbes (Desulfurococcales, Thermoprotales, and Sulfolobales) were more abundant at deeper layers (4 mbsf; corresponding to 3 K Radiocarbon years before present, Holocene Epoch). Taxonomic analyzes and functional gene identification associated with anaerobic methane oxidation (e.g. monomethylamine methyltransferase (mtmB), trimethylamine methyltransferase (mttB) and CO dehydrogenase/acetyl-CoA synthase delta subunit) and sulfate reduction indicated the dominance of Campylobacteria (Sulfurimonas) at deeper sediment layers. Gene sequences related to assimilation of inorganic sulfur increased with depth, while organic sulfur related sequences decrease, accompanying the clear reduction in the concentration of sulfur, organic carbon and chla torwards deeper layers. Analyzes of metagenome assembled genomes also led to the discovery of a novel order within the phylum Acidobacteriota, named Guanabacteria. This novel order had several in silico phenotyping features that differentiate it from closely related phylogenetic neighbors (e.g. Acidobacteria, Aminicenantes, and Thermoanaerobaculum), including several genes (carbon monoxide dehydrogenase, CO dehydrogenase/CO-methylating acetyl-CoA synthase complex subunit beta, heterodisulfide reductase, sulfite exporter TauE/SafE family protein, sulfurtransferase) that relevant for the S and C cycles. Furthermore, the recovered Bathyarchaeota genome SS9 illustrates the methanogenic potential in deeper sediment layer.

Infectious diseases such as white plague syndrome (WPS) and black band disease (BBD) have caused massive coral loss worldwide. We performed a metaproteomic study on the Abrolhos coral Mussismilia braziliensis to define the types of proteins expressed in healthy corals compared to WPS- and BBD-affected corals. A total of 6363 MS/MS spectra were identified as 361 different proteins. Healthy corals had a set of proteins that may be considered markers of holobiont homoeostasis, including tubulin, histone, Rab family, ribosomal, peridinin-chlorophyll a-binding protein, F0F1-type ATP synthase, alpha-iG protein, calmodulin and ADP-ribosylation factor. Cnidaria proteins found in healthy M. braziliensis were associated with Cnidaria-Symbiodinium endosymbiosis and included chaperones (hsp70, hsp90 and calreticulin), structural and membrane modelling proteins (actin) and proteins with functions related to intracellular vesicular traffic (Rab7 and ADP-ribosylation factor 1) and signal transduction (14-3-3 protein and calmodulin). WPS resulted in a clear shift in the predominance of proteins, from those related to aerobic nitrogen-fixing bacteria (i.e. Rhizobiales, Sphingomonadales and Actinomycetales) in healthy corals to those produced by facultative/anaerobic sulphate-reducing bacteria (i.e. Enterobacteriales, Alteromonadales, Clostridiales and Bacteroidetes) in WPS corals. BBD corals developed a diverse community dominated by cyanobacteria and sulphur cycle bacteria. Hsp60, hsp90 and adenosylhomocysteinase proteins were produced mainly by cyanobacteria in BBD corals, which is consistent with elevated oxidative stress in hydrogen sulphide- and cyanotoxin-rich environments. This study demonstrates the usefulness of metaproteomics for gaining better comprehension of coral metabolic status in health and disease, especially in reef systems such as the Abrolhos that are suffering from the increase in global and local threatening events.

To evaluate the impacts of the Fundao tailings dam failure (Minas Gerais, Brazil) on water quality of the Doce River, we analyzed metagenomics and physicochemical parameters during the month of the disaster and again 6 and 10 months after the disaster. To compare dam conditions before and after the failure, we performed a meta-analysis of physicochemical data from a public database. Immediately after the failure, suspended particulate matter (SPM) in the Doce River was 225–1877 mg L−1. Turbidity and dissolved aluminum and iron concentrations were extremely high, whereas dissolved oxygen was below Brazilian legislation norm (

We report here the genome sequences of the novel isolates G62T and G98T from rhodoliths. The nearly complete genomes consisted of 4.7 Mbp (4,233 coding sequences [CDS]) for G62T and 4.5 Mbp (4,085 CDS) for G98T., We report here the genome sequences of the novel isolates G62T and G98T from rhodoliths. The nearly complete genomes consisted of 4.7 Mbp (4,233 coding sequences [CDS]) for G62T and 4.5 Mbp (4,085 CDS) for G98T. Genomic taxonomy places these new genomes into 2 new species.

The collapse of Fundao dam in Mariana, Minas Gerais, Brazil, released more than 50 million cubic meters of ore tailings into the environment, representing the world's largest mining disaster. Three analyses estimating the forest loss to the ore tailings were produced soon after the collapse but the values varied threefold between them due to differences in objective and spatial resolution. Our aim was to estimate the riverside forest loss due to the flooding of the ore tailings. We analyzed Landsat Normalized Difference Vegetation Indexes (NDVI) with the digital elevation model (DEM) specific for flooded forest and limited to analyze an area floodable and contiguous from the water stream. Our forest loss quantification resulted in the same order of magnitude than the two of previous estimates. The area other than forest flooded by the ore tailings accounted for 1176.6 ha. The loss of the forest area due to the collapse was 457.6 ha and concentrated along the first 74 km from the Fundao Dam.

Corals of genus Mussismilia (Mussidae) are one of the oldest extant clades of scleractinians. These Neogene relicts are endemic to the Brazilian coast and represent the main reef-building corals in the Southwest Atlantic Ocean (SAO). The relatively low-diversity/high-endemism SAO coralline systems are under rapid decline from emerging diseases and other local and global stressors, but have not been severely affected by coral bleaching. Despite the biogeographic significance and importance for understanding coral resilience, there is scant information about the diversity of Symbiodinium in this ocean basin. In this study, we established the first culture collections of Symbiodinium from Mussismilia hosts, comprising 11 isolates, four of them obtained by fluorescent-activated cell sorting (FACS). We also analyzed Symbiodinium diversity directly from Mussismilia tissue samples (N = 16) and characterized taxonomically the cultures and tissue samples by sequencing the dominant ITS2 region. Symbiodinium strains A4, B19, and C3 were detected. Symbiodinium C3 was predominant in the larger SAO reef system (Abrolhos), while Symbiodinium B19 was found only in deep samples from the oceanic Trindade Island. Symbiodinium strains A4 and C3 isolates were recovered from the same Mussismilia braziliensis coral colony. In face of increasing threats, these results indicate that Symbiodinium community dynamics shall have an important contribution for the resilience of Mussismilia spp. corals.

We present here the draft genome sequence of Pseudoalteromonas sp. strain PAB 2.2, isolated from water of Parcel de Abrolhos coral reef (17°57′32.7″; 38°30′20.3″), on Abrolhos Bank, at a depth of 12 m. The assembly consists of 4,434,635 bp and contains 40 contigs, with a G+C content of 41.60%.

We present here the draft genome sequence of Pseudoalteromonas sp. strain PAB 2.2, isolated from water of Parcel de Abrolhos coral reef (17°57′32.7″; 38°30′20.3″), on Abrolhos Bank, at a depth of 12 m. The assembly consists of 4,434,635 bp and contains 40 contigs, with a G+C content of 41.60%.

As coral reef habitats decline worldwide, some reefs are transitioning from coral- to algal-dominated benthos with the exact cause for this shift remaining elusive. Increases in the abundance of microbes in the water column has been correlated with an increase in coral disease and reduction in coral cover. Here we investigated how multiple reef organisms influence microbial communities in the surrounding water column. Our study consisted of a field assessment of microbial communities above replicate patches dominated by a single macro-organism. Metagenomes were constructed from 20 L of water above distinct macro-organisms, including (1) the coral Mussismilia braziliensis, (2) fleshy macroalgae (Stypopodium, Dictota and Canistrocarpus), (3) turf algae, and (4) the zoanthid Palythoa caribaeorum and were compared to the water microbes collected 3 m above the reef. Microbial genera and functional potential were annotated using MG-RAST and showed that the dominant benthic macro-organisms influence the taxa and functions of microbes in the water column surrounding them, developing a specific “aura-biome”. The coral aura-biome reflected the open water column, and was associated with Synechococcus and functions suggesting oligotrophic growth, while the fleshy macroalgae aura-biome was associated with Ruegeria, Pseudomonas, and microbial functions suggesting low oxygen conditions. The turf algae aura-biome was associated with Vibrio, Flavobacterium, and functions suggesting pathogenic activity, while zoanthids were associated with Alteromonas and functions suggesting a stressful environment. Because each benthic organism has a distinct aura-biome, a change in benthic cover will change the microbial community of the water, which may lead to either the stimulation or suppression of the recruitment of benthic organisms.

We analyzed the diversity and population structure of the 775 Vibrio isolates from different locations of the southwestern Atlantic Ocean (SAO), including St. Peter and St. Paul Archipelago (SPSPA), Abrolhos Bank (AB) and the St. Sebastian region (SS), between 2005 and 2010. In this study, 195 novel isolates, obtained from seawater and major benthic organisms (rhodoliths and corals), were compared with a collection of 580 isolates previously characterized (available at www.taxvibrio.lncc.br). The isolates were distributed in 8 major habitat spectra according to AdaptML analysis on the basis of pyrH phylogenetic reconstruction and ecological information, such as isolation source (i.e., corals: Madracis decactis, Mussismilia braziliensis, M. hispida, Phyllogorgia dilatata, Scolymia wellsi; zoanthids: Palythoa caribaeorum, P. variabilis and Zoanthus solanderi; fireworm: Hermodice carunculata; rhodolith; water and sediment) and sampling site regions (SPSPA, AB and SS). Ecologically distinct groups were discerned through AdaptML, which finds phylogenetic groups that are significantly different in their spectra of habitat preferences. Some habitat spectra suggested ecological specialization, with habitat spectra 2, 3, and 4 corresponding to specialization on SPSPA, AB, and SS, respectively. This match between habitat and location may reflect a minor exchange of Vibrio populations between geographically isolated benthic systems. Moreover, we found several widespread Vibrio species predominantly from water column, and different populations of a single Vibrio species from H. carunculata in ecologically distinct groups (H-1 and H-8 respectively). On the other hand, AdaptML detected phylogenetic groups that are found in both the benthos and in open water. The ecological grouping observed suggests dispersal and connectivity between the benthic and pelagic systems in AB. This study is a first attempt to characterize the biogeographic distribution of vibrios in both seawater and several benthic hosts in the SAO. The benthopelagic coupling observed here stands out the importance of vibrios in the global ocean health.

The Brazilian endemic scleractinian corals, genus Mussismilia, are among the main reef builders of the South Atlantic and are threatened by accelerating rates of disease. To better understand how holobiont microbial populations interact with corals during health and disease and to evaluate whether selective pressures in the holobiont or neutral assembly shape microbial composition, we have examined the microbiota structure of Mussismilia corals according to coral lineage, environment, and disease/health status. Microbiota of three Mussismilia species (Mussismilia harttii, Mussismilia hispida, and Mussismilia braziliensis) was compared using 16S rRNA pyrosequencing and clone library analysis of coral fragments. Analysis of biological triplicates per Mussismilia species and reef site allowed assessment of variability among Mussismilia species and between sites for M. braziliensis. From 173,487 V6 sequences, 6,733 coral- and 1,052 water-associated operational taxonomic units (OTUs) were observed. M. braziliensis microbiota was more similar across reefs than to other Mussismilia species microbiota from the same reef. Highly prevalent OTUs were more significantly structured by coral lineage and were enriched in Alpha- and Gammaproteobacteria. Bacterial OTUs from healthy corals were recovered from a M. braziliensis skeleton sample at twice the frequency of recovery from water or a diseased coral suggesting the skeleton is a significant habitat for microbial populations in the holobiont. Diseased corals were enriched with pathogens and opportunists (Vibrios, Bacteroidetes, Thalassomonas, and SRB). Our study examines for the first time intra- and inter-specific variability of microbiota across the genus Mussismilia. Changes in microbiota may be useful indicators of coral health and thus be a valuable tool for coral reef management and conservation., MIT International Science and Technology Initiatives (MIT-Brazil seed Grants Program), Conselho Nacional de Pesquisas (Brazil) (Grant), Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro, Brazil. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (grant), United States. Embassy (grant), Massachusetts Institute of Technology. Center for Environmental Health Sciences

Urban pigeons (Columba livia) are birds that coexist with humans, especially in urban environments. It is accepted that their adaption to these environments is mainly related to three basic reasons: (i) the architecture of urban buildings, monuments and works of engineering has gaps, cracks and spaces that can be used for landing, nesting and shelter, protecting the birds from the weather; (ii) the absence of natural predators; and (iii) availability of food, as these birds are omnivorous, somewhat selective in their feeding (23). In this way pigeons may have an important role in spreading zoonotic agents to humans as they are a natural reservoir of many microorganisms, including pathogenic enterobacteria and other microbial groups such as Enterococcus(6, 19, 41). The transmission of infectious diseases happens usually by either ingestion of food, water, the handling of products contaminated with their feces. The dispersion of wind-dried pigeon droppings should also be considered as a route of pathogen spread (29, 36). Enterococci are Gram-positive, facultative anaerobes, arranged in pairs and short chains. These bacteria were considered as harmless inhabitants of the gastrointestinal tracts of humans and animals, being commonly isolated from feces, water, plants, soil and food products (14, 33). Despite their low virulence, studies have documented that enterococci have been emerging as significant human pathogens (21, 25). Due to their frequent association with infections and their increasing antimicrobial resistance, enterococci have become a serious problem in human medicine as a pathogenic microorganism, as well as nosocomial infection-associated bacteria. Besides natural antimicrobial resistance among Enterococcus species to several antibiotics currently used, they may also acquire resistance determinants through horizontal gene transfer (5). Furthermore, especially regarding bacteria spread environmentally, the release of toxic and heavy metals in various forms into the environment may contribute to the rise of antimicrobial resistance. In the last decade it was stated that antibiotic-resistant bacteria could arise in the environment through co- or cross-resistance to metals (30). Considering global issues, such as public health, urban planning and environmental problems, as pigeon populations increase, especially in Brazilian cities, prospective studies are needed to better assess the risks of acquired infections related to multidrug-resistant bacteria that might be spread or released by urban birds (29, 41, 44). This study aimed to evaluate Enterococcus spp. occurrence in fresh fecal samples isolated from urban pigeons in a southeastern Brazilian city, their antimicrobial susceptibility and their toxic metal tolerance patterns.

The health of the coral reefs of the Abrolhos Bank (Southwestern Atlantic) was characterized with a holistic approach using measurements of four ecosystem components: (i) inorganic and organic nutrient concentrations, [1] fish biomass, [1] macroalgal and coral cover and (iv) microbial community composition and abundance. The possible benefits of protection from fishing were particularly evaluated by comparing sites with varying levels of protection. Two reefs within the well-enforced no-take area of the National Marine Park of Abrolhos (Parcel dos Abrolhos and California) were compared with two unprotected coastal reefs (Sebastião Gomes and Pedra de Leste) and one legally protected but poorly enforced coastal reef (the "paper park" of Timbebas Reef). The fish biomass was lower and the fleshy macroalgal cover was higher in the unprotected reefs compared with the protected areas. The unprotected and protected reefs had similar seawater chemistry. Lower vibrio CFU counts were observed in the fully protected area of California Reef. Metagenome analysis showed that the unprotected reefs had a higher abundance of archaeal and viral sequences and more bacterial pathogens, while the protected reefs had a higher abundance of genes related to photosynthesis. Similar to other reef systems in the world, there was evidence that reductions in the biomass of herbivorous fishes and the consequent increase in macroalgal cover in the Abrolhos Bank may be affecting microbial diversity and abundance. Through the integration of different types of ecological data, the present study showed that protection from fishing may lead to greater reef health. The data presented herein suggest that protected coral reefs have higher microbial diversity, with the most degraded reef (Sebastião Gomes) showing a marked reduction in microbial species richness. It is concluded that ecological conditions in unprotected reefs may promote the growth and rapid evolution of opportunistic microbial pathogens.

Marine sponges are the oldest Metazoa, very often presenting a complex microbial consortium. Such is the case of the marine sponge Arenosclera brasiliensis, endemic to Rio de Janeiro State, Brazil. In this investigation we characterized the diversity of some of the culturable heterotrophic bacteria living in association with A. brasiliensis and determined their antimicrobial activity. The genera Endozoicomonas (N = 32), Bacillus (N = 26), Shewanella (N = 17), Pseudovibrio (N = 12), and Ruegeria (N = 8) were dominant among the recovered isolates, corresponding to 97% of all isolates. Approximately one third of the isolates living in association with A. brasiliensis produced antibiotics that inhibited the growth of Bacillus subtilis, suggesting that bacteria associated with this sponge play a role in its health.