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The number of individuals seeking help for environmentally related psychological distress (eco-distress) is rising. This study investigates the role of nature relatedness and social media in the et...

As the population of older adults increases, it is important to understand what may assist every older person to live well and longer. Using a systematic review, this study examined the longitudinal consequences of self-perceptions of ageing (SPA), a measure of internalized stereotypes of ageing, in participants 50 years or older. The sample comprised 21 studies published in English that used the Attitudes Toward Own Aging (ATOA) scale to measure SPA. Studies were conducted in the United States (10), Germany (7), Australia (2), and one each from Israel and Switzerland. Risk of bias was low, study design and assessment showed good to high quality, and the ATOA scale was reliable in all studies. Primary outcomes were physiological (N = 15; longevity and better health, health behaviors, and diseases) and psychological (N = 6; depression, cognitive function, and other psychological outcomes) rather than social. More positive SPA was consistently associated with healthier longitudinal outcomes, including better self-rated health and less obesity, greater longevity, better performance of the activities of daily living, less depression, and better cognitive functioning (including reductions in cognitive decline and incidence of dementia). These were both direct and indirect pathways and provide support for the consequences of ageing stereotypes, providing support for Levy's Stereotype Embodiment theory. The results have public health implications, broadly as community messaging about the benefits of positive SPA and usual and healthy ageing, and more narrowly in using ATOA to screen for middle-aged adults with negative SPA to prevent future physical and psychological decline. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

OBJECTIVE Research and theory suggest the aetiological nature and symptomatic profile of eating disorders (EDs) can be explained by multiple factors, including the development of early maladaptive schemas (EMS). Yet, there is lack of consensus regarding the evidence supporting the relationship between EMS and EDs. Therefore, this systematic review aimed to examine existing literature concerning the relationship between different ED diagnoses and EMS to provide a synthesis and evaluation of relevant research. METHOD A comprehensive literature search of four electronic databases was conducted and studies were included that examined the association between EMS and EDs. Studies were required to use a variant of Young Schema Questionnaire and establish ED diagnosis or symptomology using self-report questionnaires or clinical interview. RESULTS A total of 29 studies were included in the review. Compared to healthy controls and varying clinical populations, individuals with EDs generally reported significantly higher scores across all EMS except for Entitlement. Furthermore, Unrelenting Standards consistently appeared as a significant EMS across all ED diagnoses whilst Insufficient Self-Control was significantly lower in ED diagnoses with restrictive behaviour compared to diagnoses with binge eating or purging behaviour. DISCUSSION Research supports significant associations between EMS and EDs, which may contribute to our understanding of ED aetiology, including different diagnostic categories. This review underscores the need for studies to explore more gender and age diverse samples and highlights important implications for practitioners.

Oysters play an important role in coastal ecology and are a globally popular seafood source. However, their filter feeding lifestyle enables coastal pathogens, toxins, and pollutants to accumulate in their tissues, potentially endangering human health. For example, bacterial pathogens from both marine and terrestrial sources concentrate in oysters and can cause human illness when oysters are consumed raw. While pathogen concentrations in coastal waters are often linked to environmental conditions and runoff events, these do not always correlate with pathogen concentrations in oysters. Additional factors related to oyster hosts and the microbial ecology of pathogenic bacteria likely play a role in accumulation but are poorly understood. In this study, we investigated whether microbial communities in water and oysters were linked to accumulation of fecal indicators,Vibrio parahaemolyticus, andVibrio vulnificus. Site-specific environmental conditions significantly influenced the composition and diversity of water microbial communities, which were linked to the highest concentrations of bothVibriospp. and fecal indicator bacteria. Oyster microbial communities, however, were less impacted by environmental variability and exhibited less variability in microbial community diversity and accumulation of target bacteria. Instead, changes in specific microbial taxa in oyster and water samples, particularly in oyster digestive glands, were linked to elevated potential pathogens in oysters, especiallyV. parahaemolyticus. This included an increase in cyanobacteria in both water and oyster digestive gland microbial communities, which could represent an environmental vector forVibriospp. transport and decreased relative abundance ofMycoplasmaand other key members of the oyster digestive gland microbiota. These findings suggest that host and microbial factors, in addition to environmental variables, may influence pathogen accumulation in oysters.

Production and use of proteins is under strong selection in microbes, but it is unclear how proteome-level traits relate to ecological strategies. We identified and quantified proteomic traits of eukaryotic microbes and bacteria through an Antarctic phytoplankton bloom using in situ metaproteomics. Different taxa, rather than different environmental conditions, formed distinct clusters based on their ribosomal and photosynthetic proteomic proportions, and we propose that these characteristics relate to ecological differences. We defined and used a proteomic proxy for regulatory cost, which showed that SAR11 had the lowest regulatory cost of any taxa we observed at our summertime Southern Ocean study site. Haptophytes had lower regulatory cost than diatoms, which may underpin haptophyte-to-diatom bloom progression in the Ross Sea. We were able to make these proteomic trait inferences by assessing various sources of bias in metaproteomics, providing practical recommendations for researchers in the field. We have quantified several proteomic traits (ribosomal and photosynthetic proteomic proportions, regulatory cost) in eukaryotic and bacterial taxa, which can then be incorporated into trait-based models of microbial communities that reflect resource allocation strategies.

Objective: Clark and Wells cognitive model of social anxiety has significant empirical support and has informed evidence-based treatments for Social Anxiety Disorder. However, to date, research for...

Marine microeukaryotes play a fundamental role in biogeochemical cycling through the transfer of energy to higher trophic levels and vertical carbon transport. Despite their global importance, microeukaryote physiology, nutrient metabolism and contributions to carbon cycling across offshore ecosystems are poorly characterized. Here, we observed the prevalence of dinoflagellates along a 4,600-km meridional transect extending across the central Pacific Ocean, where oligotrophic gyres meet equatorial upwelling waters rich in macronutrients yet low in dissolved iron. A combined multi-omics and geochemical analysis provided a window into dinoflagellate metabolism across the transect, indicating a continuous taxonomic dinoflagellate community that shifted its functional transcriptome and proteome as it extended from the euphotic to the mesopelagic zone. In euphotic waters, multi-omics data suggested that a combination of trophic modes were utilized, while mesopelagic metabolism was marked by cytoskeletal investments and nutrient recycling. Rearrangement in nutrient metabolism was evident in response to variable nitrogen and iron regimes across the gradient, with no associated change in community assemblage. Total dinoflagellate proteins scaled with particulate carbon export, with both elevated in equatorial waters, suggesting a link between dinoflagellate abundance and total carbon flux. Dinoflagellates employ numerous metabolic strategies that enable broad occupation of central Pacific ecosystems and play a dual role in carbon transformation through both photosynthetic fixation in the euphotic zone and remineralization in the mesopelagic zone.

The exchange of metabolites mediates algal and bacterial interactions that maintain ecosystem function. Yet, while thousands of metabolites are produced, only a few molecules have been identified in these associations. Using the ubiquitous microalgae Pseudo-nitzschia sp., as a model, we employed an untargeted metabolomics strategy to assign structural characteristics to the metabolites that distinguished specific diatom-microbiome associations. We cultured five species of Pseudo-nitzschia, including two species that produced the toxin domoic acid, and examined their microbiomes and metabolomes. A total of 4826 molecular features were detected by tandem mass spectrometry. Only 229 of these could be annotated using available mass spectral libraries, but by applying new in silico annotation tools, characterization was expanded to 2710 features. The metabolomes of the Pseudo-nitzschia-microbiome associations were distinct and distinguished by structurally diverse nitrogen compounds, ranging from simple amines and amides to cyclic compounds such as imidazoles, pyrrolidines and lactams. By illuminating the dark metabolomes, this study expands our capacity to discover new chemical targets that facilitate microbial partnerships and uncovers the chemical diversity that underpins algae-bacteria interactions.

Background:Premature ejaculation (PE) and erectile dysfunction (ED) are prevalent sexual problems, with evidence to suggest variation across sexual orientation. Contributing factors have traditionally been divided into organic and psychological categories. While limited research has found support for the influence of metacognitive beliefs, these studies did not investigate potential differences in sexual orientation.Aim:The current study aimed to investigate the differences in metacognitive beliefs in men with or without PE and/or ED and whether these varied according to sexual orientation.Method:A sample of 531 men was recruited (65 met criteria for PE only, 147 for ED, 83 with PE and ED, and 236 healthy controls). Within this sample, 188 men identified as heterosexual, 144 as bisexual, and 199 as homosexual. Participants completed a cross-sectional online survey consisting of psychometric measures.Results:Participants with PE and ED were significantly higher in cognitive confidence, thoughts concerning uncontrollability and danger, and need to control thoughts than PE only, ED only, and healthy controls. Furthermore, the PE only group was significantly higher than healthy controls for cognitive confidence, with the ED significantly higher for thoughts concerning uncontrollability and danger. There were no significant differences between differing sexual orientations for men with/or without PE and/or ED.Conclusions:Congruent with previous research, metacognitive beliefs play a role in PE and/or ED, although this is not exclusive to sexual orientation. The findings highlight that assessment and intervention regarding metacognitive beliefs may be beneficial for men of all sexual orientations with PE and/or ED.

Dysregulated sexuality refers to sexual thoughts, feelings, and behaviors that are perceived as out of control and distressing. This study aimed to explore the relationships between desire thinking...

Previous research has shown that idealised images of men in the media have the capacity to trigger body dissatisfaction in male viewers. However, little is known about these effects across diverse ...

Domoic acid (DA), the causative agent of amnesic shellfish poisoning, is produced by select organisms within two distantly related algal clades: planktonic diatoms and red macroalgae. The biosynthetic pathway to isodomoic acid A was recently solved in the harmful algal bloom-forming diatom Pseudonitzschia multiseries, establishing the genetic basis for the global production of this potent neurotoxin. Herein, we sequenced the 507-Mb genome of Chondria armata, the red macroalgal seaweed from which DA was first isolated in the 1950s, identifying several copies of the red algal DA (rad) biosynthetic gene cluster. The rad genes are organized similarly to the diatom DA biosynthesis cluster in terms of gene synteny, including a cytochrome P450 (CYP450) enzyme critical to DA production that is notably absent in red algae that produce the simpler kainoid neurochemical, kainic acid. The biochemical characterization of the N-prenyltransferase (RadA) and kainoid synthase (RadC) enzymes support a slightly altered DA biosynthetic model in C. armata via the congener isodomoic acid B, with RadC behaving more like the homologous diatom enzyme despite higher amino acid similarity to red algal kainic acid synthesis enzymes. A phylogenetic analysis of the rad genes suggests unique origins for the red macroalgal and diatom genes in their respective hosts, with native eukaryotic CYP450 neofunctionalization combining with the horizontal gene transfer of N-prenyltransferases and kainoid synthases to establish DA production within the algal lineages.

The ecological and oceanographic processes that drive the response of pelagic ocean microbiomes to environmental changes remain poorly understood, particularly in coastal upwelling ecosystems. Here we show that seasonal and interannual variability in coastal upwelling predicts pelagic ocean microbiome diversity and community structure in the Southern California Current region. Ribosomal RNA gene sequencing, targeting prokaryotic and eukaryotic microbes, from samples collected seasonally during 2014-2020 indicate that nitracline depth is the most robust predictor of spatial microbial community structure and biodiversity in this region. Striking ecological changes occurred due to the transition from a warm anomaly during 2014-2016, characterized by intense stratification, to cooler conditions in 2017-2018, representative of more typical upwelling conditions, with photosynthetic eukaryotes, especially diatoms, changing most strongly. The regional slope of nitracline depth exerts strong control on the relative proportion of highly diverse offshore communities and low biodiversity, but highly productive nearshore communities.

Domoic acid (DA), the causative agent of amnesic shellfish poisoning, is produced by select organisms within two distantly related algal clades: planktonic diatoms and red macroalgae. The biosynthetic pathway to isodomoic acid A was recently solved in the harmful algal bloom-forming diatom

Scarce dissolved surface ocean concentrations of the essential algal micronutrient zinc suggest that Zn may influence the growth of phytoplankton such as diatoms, which are major contributors to marine primary productivity. However, the specific mechanisms by which diatoms acclimate to Zn deficiency are poorly understood. Using global proteomic analysis, we identified two proteins (ZCRP-A/B, Zn/Co Responsive Protein A/B) among four diatom species that became abundant under Zn/Co limitation. Characterization using reverse genetic techniques and homology data suggests putative Zn/Co chaperone and membrane-bound transport complex component roles for ZCRP-A (a COG0523 domain protein) and ZCRP-B, respectively. Metaproteomic detection of ZCRPs along a Pacific Ocean transect revealed increased abundances at the surface (

Diatom metacommunities are structured by environmental, historical, and spatial factors that are often attributed to organism dispersal. In the McMurdo Sound region (MSR) of Antarctica, wind connects aquatic habitats through delivery of inorganic and organic matter. We evaluated the dispersal of diatoms in aeolian material and its relation to the regional diatom metacommunity using light microscopy and 18S rRNA high-throughput sequencing. The concentration of diatoms ranged from 0 to 8.76 * 106 valves · g-1 dry aeolian material. Up to 15% of whole cells contained visible protoplasm, indicating that up to 3.43 * 104 potentially viable individuals could be dispersed in a year to a single 2 cm2 site. Diatom DNA and RNA was detected at each site, reinforcing the likelihood that we observed dispersal of viable diatoms. Of the 50 known morphospecies in the MSR, 72% were identified from aeolian material using microscopy. Aeolian community composition varied primarily by site. Meanwhile, each aeolian community was comprised of morphospecies found in aquatic communities from the same lake basin. These results suggest that aeolian diatom dispersal in the MSR is spatially structured, is predominantly local, and connects local aquatic habitats via a shared species pool. Nonetheless, aeolian community structure was distinct from that of aquatic communities, indicating intra-habitat dispersal and environmental filtering also underlie diatom metacommunity dynamics. The present study confirms that a large number of diatoms are passively dispersed by wind across a landscape characterized by aeolian processes, integrating the regional flora and contributing to metacommunity structure and landscape connectivity.

Interactions between vibrio bacteria and the planktonic community impact marine ecology and human health. Many coastal Vibrio spp. can infect humans, representing a growing threat linked to increasing seawater temperatures. Interactions with eukaryotic organisms may provide attachment substrate and critical nutrients that facilitate the persistence, diversification, and spread of pathogenic Vibrio spp. However, vibrio interactions with planktonic organisms in an environmental context are poorly understood. We quantified the pathogenic Vibrio species V. cholerae, V. parahaemolyticus, and V. vulnificus monthly for 1 year at five sites and observed high abundances, particularly during summer months, with species-specific temperature and salinity distributions. Using metabarcoding, we established a detailed profile of both prokaryotic and eukaryotic coastal microbial communities. We found that pathogenic Vibrio species were frequently associated with distinct eukaryotic amplicon sequence variants (ASVs), including diatoms and copepods. Shared environmental conditions, such as high temperatures and low salinities, were associated with both high concentrations of pathogenic vibrios and potential environmental reservoirs, which may influence vibrio infection risks linked to climate change and should be incorporated into predictive ecological models and experimental laboratory systems. IMPORTANCE Many species of coastal vibrio bacteria can infect humans, representing a growing health threat linked to increasing seawater temperatures. However, their interactions with surrounding microbes in the environment, especially eukaryotic organisms that may provide nutrients and attachment substrate, are poorly understood. We quantified three pathogenic Vibrio species monthly for a duration of 1 year, finding that all three species were abundant and exhibited species-specific temperature and salinity distributions. Using metabarcoding, we investigated associations between these pathogenic species and prokaryotic and eukaryotic microbes, revealing genus and amplicon sequence variant (ASV)-specific relationships with potential functional implications. For example, pathogenic species were frequently associated with chitin-producing eukaryotes, such as diatoms in the genus Thalassiosira and copepods. These associations between high concentrations of pathogenic vibrios and potential environmental reservoirs should be considered when predicting infection risk and developing ecologically relevant model systems.

Significance Phytoplankton contribute to the Southern Ocean’s (SO) ability to absorb atmospheric CO2 and shape the stoichiometry of northward macronutrient delivery. Climate change is altering the SO environment, yet we know little about how resident phytoplankton will react to these changes. Here, we studied a natural SO community and compared responses of two prevalent, bloom-forming diatom groups to changes in temperature and iron that are projected to occur by 2100 to 2300. We found that one group, Pseudo-nitzschia, grows better under warmer low-iron conditions by managing cellular iron demand and efficiently increasing photosynthetic capacity. This ability to grow and draw down nutrients in the face of warming, regardless of iron availability, has major implications for ocean ecosystems and global nutrient cycles., The Southern Ocean (SO) harbors some of the most intense phytoplankton blooms on Earth. Changes in temperature and iron availability are expected to alter the intensity of SO phytoplankton blooms, but little is known about how these changes will influence community composition and downstream biogeochemical processes. We performed light-saturated experimental manipulations on surface ocean microbial communities from McMurdo Sound in the Ross Sea to examine the effects of increased iron availability (+2 nM) and warming (+3 and +6 °C) on nutrient uptake, as well as the growth and transcriptional responses of two dominant diatoms, Fragilariopsis and Pseudo-nitzschia. We found that community nutrient uptake and primary productivity were elevated under both warming conditions without iron addition (relative to ambient −0.5 °C). This effect was greater than additive under concurrent iron addition and warming. Pseudo-nitzschia became more abundant under warming without added iron (especially at 6 °C), while Fragilariopsis only became more abundant under warming in the iron-added treatments. We attribute the apparent advantage Pseudo-nitzschia shows under warming to up-regulation of iron-conserving photosynthetic processes, utilization of iron-economic nitrogen assimilation mechanisms, and increased iron uptake and storage. These data identify important molecular and physiological differences between dominant diatom groups and add to the growing body of evidence for Pseudo-nitzschia’s increasingly important role in warming SO ecosystems. This study also suggests that temperature-driven shifts in SO phytoplankton assemblages may increase utilization of the vast pool of excess nutrients in iron-limited SO surface waters and thereby influence global nutrient distribution and carbon cycling.

Interactions between vibrio bacteria and the planktonic community impact marine ecology and human health. Many coastal Vibrio spp. can infect humans, representing a growing threat linked to increasing seawater temperatures. Interactions with eukaryotic organisms may provide attachment substrate and critical nutrients that facilitate the persistence, diversification, and spread of pathogenic Vibrio spp. However, vibrio interactions with planktonic organisms in an environmental context are poorly understood. We quantified the pathogenic Vibrio species V. cholerae, V. parahaemolyticus, and V. vulnificus monthly for 1 year at five sites and observed high abundances, particularly during summer months, with species-specific temperature and salinity distributions. Using metabarcoding, we established a detailed profile of both prokaryotic and eukaryotic coastal microbial communities. We found that pathogenic Vibrio species were frequently associated with distinct eukaryotic amplicon sequence variants (ASVs), including diatoms and copepods. Shared environmental conditions, such as high temperatures and low salinities, were associated with both high concentrations of pathogenic vibrios and potential environmental reservoirs, which may influence vibrio infection risks linked to climate change and should be incorporated into predictive ecological models and experimental laboratory systems. IMPORTANCE Many species of coastal vibrio bacteria can infect humans, representing a growing health threat linked to increasing seawater temperatures. However, their interactions with surrounding microbes in the environment, especially eukaryotic organisms that may provide nutrients and attachment substrate, are poorly understood. We quantified three pathogenic Vibrio species monthly for a duration of 1 year, finding that all three species were abundant and exhibited species-specific temperature and salinity distributions. Using metabarcoding, we investigated associations between these pathogenic species and prokaryotic and eukaryotic microbes, revealing genus and amplicon sequence variant (ASV)-specific relationships with potential functional implications. For example, pathogenic species were frequently associated with chitin-producing eukaryotes, such as diatoms in the genus Thalassiosira and copepods. These associations between high concentrations of pathogenic vibrios and potential environmental reservoirs should be considered when predicting infection risk and developing ecologically relevant model systems.

Diatoms are among the most globally distributed and ecologically successful organisms in the modern ocean, contributing upwards of 40% of total marine primary productivity1,2. By converting dissolved silicon into biogenic silica, and photosynthetically fixing carbon dioxide into particulate organic carbon, diatoms effectively couple the silicon (Si) and carbon cycles and ballast substantial vertical flux of carbon out of the euphotic zone into the mesopelagic and deep ocean3–5. Viruses are key players in ocean biogeochemical cycles6,7, yet little is known about how viral infection specifically impacts diatom populations. Here, we show that Si limitation facilitates virus infection and mortality in diatoms in the highly productive coastal waters of the California Current Ecosystem. Using metatranscriptomic analysis of cell-associated diatom viruses and targeted quantification of extracellular viruses, we found a link between Si stress and the early, active and lytic stages of viral infection. This relationship was also observed in cultures of the bloom-forming diatom Chaetoceros tenuissimus, where Si stress accelerated virus-induced mortality. Together, these findings contextualize viruses within the ecophysiological framework of Si availability and diatom-mediated biogeochemical cycling. Using metatranscriptomics of diatom-associated viruses and quantification of extracellular viruses in coastal water samples, the authors link silicon limitation to increased virus-induced mortality of diatoms, which could have implications for marine biogeochemical cycling.

International audience; Photoacclimation consists of short-and long-term strategies used by photosynthetic organisms to adapt to dynamic light environments. Observable photophysiology changes resulting from these strategies have been used in coarse-grained models to predict light-dependent growth and photosynthetic rates. However, the contribution of the broader metabolic network , relevant to species-specific strategies and fitness, is not accounted for in these simple models. We incorporated photophysiology experimental data with genome-scale modeling to characterize organism-level, light-dependent metabolic changes in the model diatom Phaeodactylum tricornutum. Oxygen evolution and photon absorption rates were combined with condition-specific biomass compositions to predict metabolic pathway usage for cells acclimated to four different light intensities. Photorespiration, an ornithine-glutamine shunt, and branched-chain amino acid metabolism were hypothesized as the primary intercompartment reductant shuttles for mediating excess light energy dissipation. Additionally, simulations suggested that carbon shunted through photorespiration is recycled back to the chloroplast as pyruvate, a mechanism distinct from known strategies in photosynthetic organisms. Our results suggest a flexible metabolic network in P. tricornutum that tunes intercompart-ment metabolism to optimize energy transport between the organelles, consuming excess energy as needed. Characterization of these intercompartment reductant shuttles broadens our understanding of energy partitioning strategies in this clade of ecologically important primary producers.

Production and use of proteins is under strong selection in microbes, but it’s unclear how proteome-level traits relate to ecological strategies. We identified and quantified proteomic traits of eukaryotic and prokaryotic microbes through an Antarctic phytoplankton bloom using in situ metaproteomics. To do this, we first used simulations, cultures, and bioinformatic methods to rigorously assess our inferences about various proteomic traits and use these assessments to provide several practical recommendations for researchers using metaproteomics. Different taxa, rather than different environmental conditions, formed distinct clusters based on their ribosomal and photosynthetic proteomic proportions, and we propose that these characteristics relate to ecological differences. We defined and used a proteomic proxy for regulatory cost, which showed that SAR11 had the lowest regulatory cost of any taxa we observed at our summertime Southern Ocean study site. Haptophytes had lower regulatory cost than diatoms, which may underpin haptophyte-to-diatom bloom progression in the Ross Sea. Using metaproteomics, we have quantified several proteomic traits (ribosomal and photosynthetic proteomic proportions, regulatory cost) in eukaryotic and prokaryotic taxa, which can then be incorporated into trait-based models of microbial communities that reflect resource allocation strategies.

Bioactive trace metals are critical micronutrients for marine microorganisms due to their role in mediating biological redox reactions, and complex biogeochemical processes control their distributions. Hydrothermal vents may represent an important source of metals to microorganisms, especially those inhabiting low iron waters, such as in the southwest Pacific Ocean. Previous measurements of primordial 3He indicate a significant hydrothermal source originating in the Northeast (NE) Lau Basin, with the plume advecting into the southwest Pacific Ocean at 1,500–2,000 m depth (Lupton et al. 2004). Studies investigating the long range of trace metals associated with such dispersing plumes are rare, and the biogeochemical impacts on local microbial physiology have not yet been described. Here we quantified dissolved metals and assessed microbial metaproteomes across a transect spanning the tropical and equatorial Pacific with a focus on the hydrothermally active NE Lau Basin, and report elevated iron and manganese concentrations across 441 km of the southwest Pacific. The most intense signal was detected near the Mangatolu Triple Junction (MTJ) and Northeast Lau Spreading Center (NELSC), in close proximity to the previously reported 3He signature. Protein content in distal plume-influenced seawater, which was high in metals, was overall similar to background locations, though key prokaryotic proteins involved in metal and organic uptake, protein degradation and chemoautotrophy were comparatively abundant compared to deep waters outside of the distal plume. Our results demonstrate that trace metals derived from the NE Lau Basin are transported over appreciable distances into the southwest Pacific Ocean, and that bioactive chemical resources released from submarine vent systems are utilized by surrounding deep sea microbes, influencing both their physiology and their contributions to ocean biogeochemical cycling.

A near-complete diploid nuclear genome and accompanying circular mitochondrial and chloroplast genomes have been assembled from the elite commercial diatom species Nitzschia hildebrandi. The 50 Mbp haploid size of the nuclear genome is nearly double that of model diatom Phaeodactylum tricornutum, but 30% smaller than closer relative Fragilariopsis cylindrus. Diploid assembly, which was facilitated by low levels of allelic heterozygosity (2.7%), included 14 candidate chromosome pairs composed of long, syntenic contigs, covering 93% of the total assembly. Telomeric ends were capped with an unusual 12-mer, G-rich, degenerate repeat sequence. Predicted proteins were highly enriched in strain-specific marker domains associated with cell-surface adhesion, biofilm formation, and raphe system gliding motility. Expanded species-specific families of carbonic anhydrases suggest potential enhancement of carbon concentration efficiency, and duplicated glycolysis and fatty acid synthesis pathways across cytosolic and organellar compartments may enhance peak metabolic output, contributing to competitive success over other organisms in mixed cultures. The N. hildebrandi genome delivers a robust new reference for future functional and transcriptomic studies to illuminate the physiology of benthic pennate diatoms and harness their unique adaptations to support commercial algae biomass and bioproduct production.

Author(s): Petras, Daniel; Phelan, Vanessa V; Acharya, Deepa; Allen, Andrew E; Aron, Allegra T; Bandeira, Nuno; Bowen, Benjamin P; Belle-Oudry, Deirdre; Boecker, Simon; Cummings, Dale A; Deutsch, Jessica M; Fahy, Eoin; Garg, Neha; Gregor, Rachel; Handelsman, Jo; Navarro-Hoyos, Mirtha; Jarmusch, Alan K; Jarmusch, Scott A; Louie, Katherine; Maloney, Katherine N; Marty, Michael T; Meijler, Michael M; Mizrahi, Itzhak; Neve, Rachel L; Northen, Trent R; Molina-Santiago, Carlos; Panitchpakdi, Morgan; Pullman, Benjamin; Puri, Aaron W; Schmid, Robin; Subramaniam, Shankar; Thukral, Monica; Vasquez-Castro, Felipe; Dorrestein, Pieter C; Wang, Mingxun | Abstract: AbstractAccess to web-based platforms has enabled scientists to perform research remotely. A critical aspect of mass spectrometry data analysis is the inspection, analysis, and visualization of the raw data to validate data quality and confirm statistical observations. We developed the GNPS Dashboard, a web-based data visualization tool, to facilitate synchronous collaborative inspection, visualization, and analysis of private and public mass spectrometry data remotely.

A near-complete diploid nuclear genome and accompanying circular mitochondrial and chloroplast genomes have been assembled from the elite commercial diatom species Nitzschia inconspicua. The 50 Mbp haploid size of the nuclear genome is nearly double that of model diatom Phaeodactylum tricornutum, but 30% smaller than closer relative Fragilariopsis cylindrus. Diploid assembly, which was facilitated by low levels of allelic heterozygosity (2.7%), included 14 candidate chromosome pairs composed of long, syntenic contigs, covering 93% of the total assembly. Telomeric ends were capped with an unusual 12-mer, G-rich, degenerate repeat sequence. Predicted proteins were highly enriched in strain-specific marker domains associated with cell-surface adhesion, biofilm formation, and raphe system gliding motility. Expanded species-specific families of carbonic anhydrases suggest potential enhancement of carbon concentration efficiency, and duplicated glycolysis and fatty acid synthesis pathways across cytosolic and organellar compartments may enhance peak metabolic output, contributing to competitive success over other organisms in mixed cultures. The N. inconspicua genome delivers a robust new reference for future functional and transcriptomic studies to illuminate the physiology of benthic pennate diatoms and harness their unique adaptations to support commercial algae biomass and bioproduct production.

We used 16S, 18S, plastid and internal transcribed spacer (for Synechococcus strains) sequencing to quantify relative microbial abundances in water-column samples and on sediment-trap-collected particles across an environmental gradient in the California Current Ecosystem (CCE) spanning a > 60-fold range of surface chlorophyll. Most mixed-layer dominant eukaryotes and prokaryotes were consistently underrepresented on sinking particles. Diatoms were the only phototrophic taxa consistently overrepresented. Even within this class, however, one genus (Thalassiosira) was a particle-enriched dominant, while a similarly abundant species was poorly represented. Synechococcus was significantly enriched on sinking particles at only one of four sites, but clade I was disproportionately abundant on sinking particles throughout the region compared with clade IV, the euphotic-zone co-dominant. The most abundant microbes on particles across the CCE were organisms with distributional maxima close to the sediment-trap depth (rhizarians), microbes associated with metazoans or sinking particles as a nutritional habitat (certain alveolates, Gammaproteobacteria) and organisms that resist digestive degradation of their DNA (Thalassiosira, Synechococcus). For assessing taxon contributions of phytoplankton to carbon export, our results highlight the need for sequence-based quantitative approaches that can be used to integrate euphotic-zone abundances, compute rates and account for taxon differences in preservation of sequence markers through trophic processing.

Proteomic allocation modeling coupled with metaproteomics reveals that cellular costs govern micronutrient-controlled growth., Micronutrients control phytoplankton growth in the ocean, influencing carbon export and fisheries. It is currently unclear how micronutrient scarcity affects cellular processes and how interdependence across micronutrients arises. We show that proximate causes of micronutrient growth limitation and interdependence are governed by cumulative cellular costs of acquiring and using micronutrients. Using a mechanistic proteomic allocation model of a polar diatom focused on iron and manganese, we demonstrate how cellular processes fundamentally underpin micronutrient limitation, and how they interact and compensate for each other to shape cellular elemental stoichiometry and resource interdependence. We coupled our model with metaproteomic and environmental data, yielding an approach for estimating biogeochemical metrics, including taxon-specific growth rates. Our results show that cumulative cellular costs govern how environmental conditions modify phytoplankton growth.

Background Many species of coastal Vibrio spp. bacteria can infect humans, representing an emerging health threat linked to increasing seawater temperatures. Vibrio interactions with the planktonic community impact coastal ecology and human infection potential. In particular, interactions with eukaryotic and photosynthetic organism may provide attachment substrate and critical nutrients (e.g. chitin, phytoplankton exudates) that facilitate the persistence, diversification, and spread of pathogenic Vibrio spp.. Vibrio interactions with these organisms in an environmental context are, however, poorly understood. Results After quantifying pathogenic Vibrio species, including V. cholerae , V. parahaemolyticus , and V. vulnificus, over one year at 5 sites, we found that all three species reached high abundances, particularly during Summer months, and exhibited species-specific temperature and salinity distributions. Using metabarcoding we established a detailed profile of the both prokaryotic and eukaryotic coastal microbial communities, finding that pathogenic species were frequently associated with specific ASVs of chitin-producing eukaryotes such as diatoms and copepods. Furthermore, environmental variables had a significant effect not only on pathogenic Vibrio species but entire microbial communities, suggesting in some cases shared environmental preferences. Several significant ASV-level associations were revealed, indicating that commonly used broad taxonomic classifications (e.g. based on microbial class or Vibrio as a genus) likely mask ecologically important interactions. Shotgun metagenomic analyses revealed diverse vibrio communities that harbored additional potential vibrio pathogens, antibiotic resistance genes, and genes associated with virulence. Conclusions Taken together, this data shows that abundant pathogenic Vibrio species likely containing both antibiotic resistance and virulence-associated genes are associated with chitin producing organisms which could act as an attachment substrate, facilitating environmental persistence and horizontal gene transfer. Shared environmental conditions such as high temperatures were associated with both high levels of pathogenic vibrios and potential environmental reservoirs, which should be taken into consideration when modelling vibrio infection risk in the face of climate change and identifying biomarkers of pathogen species. Furthermore, ASV-level associations may be critical to understanding vibrio microbial ecology and should be taken into consideration while developing environmentally relevant laboratory model systems.

Eukaryotic complex phototrophs exhibit a colorful evolutionary history. At least three independent endosymbiotic events accompanied by the gene transfer from the endosymbiont to host assembled a complex genomic mosaic. Resulting patchwork may give rise to unique metabolic capabilities; on the other hand, it can also blur the reconstruction of phylogenetic relationships. The ornithine–urea cycle (OUC) belongs to the cornerstone of the metabolism of metazoans and, as found recently, also photosynthetic stramenopiles. We have analyzed the distribution and phylogenetic positions of genes encoding enzymes of the urea synthesis pathway in eukaryotes. We show here that metazoan and stramenopile OUC enzymes share common origins and that enzymes of the OUC found in primary algae (including plants) display different origins. The impact of this fact on the evolution of stramenopiles is discussed here.

Diatoms are predicted to synthesize certain amino acids within the chloroplast, including L-lysine via a diaminopimelate-dependent pathway. Herein, we report that the model diatom, Phaeodactylum tricornutum, possesses a chimeric lysine biosynthetic pathway, which coalesces bacterial and plant genes, and is terminated by a chloroplast-localized diaminopimelate decarboxylase (DAPDC, PtLYSA). We show that while RNAi ablation of PtLYSA is either synthetically lethal or concomitant with a slower growth rate, Cas9-mediated mutagenesis of PtLYSA results in recovery of heterozygous cells lines, suggesting that PtLYSA is an essential gene. Previously characterized DAPDCs are unique within the PLP-dependent decarboxylases where catalysis occurs at the D-stereocenter of the substrate and display a strict stereochemical preference for a (D,L)- or meso-substrate and not the D,D- or L,L-isomers of diaminopimelate (DAP) to synthesize L-lysine. Using decarboxylation assays and differential scanning calorimetry analyses, we validate that PtLYSA is a bona fide DAPDC and uncover its unexpected stereopromiscuous behavior in substrate specificity. The crystal structure of PtLYSA confirms the enzyme is an obligate homodimer in which both protomers reciprocally participate in the active site. The structure underscores features unique to the PtLYSA clan of DAPDC and provides structural insight into the determinants responsible for the substrate-promiscuity observed in PtLYSA.

18S and 16S amplicon library preparation protocol. DNA or RNA is usually extracted with our automated protocols from sterivex but other types of samples are occasionally used. If using RNA, first generate cDNA with Invitrogen's SuperScript III First-Strand Synthesis System. Blanks from the nucleic acid extraction should always be used as negative controls. Normally, DNA is diluted 10-fold after extraction and 1 μL of the diluted DNA or the cDNA is used for template in the PCR reaction. If DNA concentrations are very low, 1 μL of the undiluted DNA may need to be used. The library is generated with a 1-step PCR, i.e. amplicons are amplified and barcoded simultaneously. Amplicons can be generated for 16S (515F-Y/926R primers from Parada et al. 2015), 18Sv4 (V4F/V4RB primers from Balanzo et al. 2015), and 18Sv9 (1389F/1510R primers from Amaral-Zettler et al. 2009). Barcoded primers for all of these amplicons are attached to this protocol. Typically, the primers are pre-mixed into 96-well plates such that one set of 8 unique F primers (plate rows) and one set of 12 unique R primers (plate columns) are mixed to create 96 unique combinations. Reactions can then be run in a 96 well plate where template plate positions correspond to unique barcode plate positions. The i5 barcode is inline to generate higher sequence quality but also requires a customized demultiplexing workflow. When sequencing, only demultiplex based on the i7 index first. Scripts to then demultiplex based on the i5 index can be found on our Github here. We also highly recommend including mock communities in every 96-well plate.

This protocol describes our sampling strategy and techniques for the NOAA-CalCOFI Ocean Genomics (NCOG) project. In summary, seawater for DNA and RNA from multiple depths is filtered onto Sterivex filters at each station. Although the protocol is specific to this project, it is easily adaptable for other field-based sampling.

Over 7 million liters of Corexit EC9500A and EC9527A were applied to the Gulf of Mexico in response to the Deepwater Horizon oil spill. The impacts of dispersants remain under debate and negative, positive, and inconclusive impacts have been reported. Here, metatrancriptomics was applied in the context of metapangenomes to microcosms that simulated environmental conditions comparable to the hydrocarbon-rich 1,100 m deep plume. Within this microcosm study, negative effects of dispersants on microbial hydrocarbon degradation were previously reported based on activity measurements and geochemical data. Transcriptional enrichment of Colwellia, a potential dispersant degrader, followed variable time-dependent trajectories due to interactions between oil, dispersants, and nutrients. The Colwellia metapangenome captured a mixture of environmental responses linked to the Colwellia psychrerythraea 34H genome and to the genomes of other members of the Colwellia genus. The activation of genes involved in lipid degradation, nitrogen metabolism, and membrane composition under oil or nutrient availability, suggested an opportunistic growth strategy for Colwellia. In contrast, transcripts of Marinobacter, a natural hydrocarbon degrader, increased only in oil treatments. Marinobacter transcripts largely recruited to the accessory metapangenome of Marinobacter sp. C18, the closest genomic reference. A complex response involving carbon and lipid metabolism, chemotaxis and a type IV secretion system suggested active energy-dependent processes in Marinobacter. These findings highlight chemistry-dependent responses in the metabolism of key hydrocarbon-degrading bacteria and underscore that dispersant-driven selection could temper the ability of the community to respond to hydrocarbon injection.

Diatoms are one of the most successful phytoplankton groups in our oceans, being responsible for over 20% of the Earth’s photosynthetic productivity. Their chimeric genomes have genes derived from red algae, green algae, bacteria and heterotrophs, resulting in multiple isoenzymes targeted to different cellular compartments with the potential for differential regulation under nutrient limitation. The resulting interactions between metabolic pathways are not yet fully understood.We previously showed how acclimation to Cu limitation enhanced susceptibility to overreduction of the photosynthetic electron transport chain and its reorganization to favor photoprotection over light-harvesting in the oceanic diatom Thalassiosira oceanica (Hippmann et al., 2017). In order to gain a better understanding of the overall metabolic changes that help alleviate the stress of Cu limitation, we have further analyzed the comprehensive proteomic datasets generated in that study to identify differentially expressed proteins involved in carbon, nitrogen and oxidative stress-related metabolic pathways.Metabolic pathway analysis showed integrated responses to Cu limitation. The up-regulation of ferredoxin (Fdx) was correlated with up-regulation of plastidial Fdx-dependent isoenzymes involved in nitrogen assimilation as well as enzymes involved in glutathione synthesis, thus integrating nitrogen uptake and metabolism with photosynthesis and oxidative stress resistance. The differential expression of glycolytic isoenzymes located in the chloroplast and mitochondria may enable them to channel both excess electrons and/or ATP between these compartments. Additional evidence for chloroplast-mitochondrial cross-talk is the increased expression of chloroplast and mitochondrial proteins involved in the proposed malate shunt under Cu limitation.One sentence summaryDiatoms adapt to Cu limitation by regulating their large repertoire of isoenzymes to channel electrons away from the chloroplast, enhance nitrogen uptake, and integrate the oxidative stress response. 123

This manuscript reports on a robot called Clio that we developed to facilitate basin-scale studies of ocean microbial communities and their biochemistry, to better understand how marine microorganisms regulate ocean and Earth system environmental cycles. Clio is designed to facilitate global-scale studies of ocean biochemistry, to move vertically through the water column with high precision, and specifically to return sensor data and samples from large swaths of the ocean ranging in depths from the surface to 6,000 m. Clio is capable of flexible, precise vertical motion that few other ocean robots can perform, and none to our knowledge over this depth range. We tested Clio extensively over several years, six cruises, and 26 dives, it is now fully operational and this manuscript describes all that we did to convince ourselves this was so. In June 2019, it completed its first large-scale ocean survey, and for which this manuscript will be the first data presentation.

The Southern Ocean (SO) harbours some of the most intense phytoplankton blooms on Earth. Changes in temperature and iron availability are expected to alter the intensity of SO phytoplankton blooms, but little is known about how environmental change will influence community composition and downstream biogeochemical processes. We performed experimental manipulations on surface ocean microbial communities from McMurdo Sound in the Ross Sea, with and without iron addition, at −0.5 °C, 3 °C, and 6 °C. We then examined nutrient uptake patterns as well as the growth and molecular responses of two dominant diatoms, Fragilariopsis and Pseudo-nitzschia, to these conditions. We found that nitrate uptake and primary productivity were elevated at increased temperature in the absence of iron addition, and were even greater at high temperature with added iron. Pseudo-nitzschia became more abundant under increased temperature without added iron, while Fragilariopsis required additional iron to benefit from warming. We attribute the apparent advantage Pseudo-nitzschia shows under warming to upregulation of iron-conserving photosynthetic processes, utilization of iron-economic nitrogen assimilation mechanisms, and increased iron uptake and storage. These data identify important molecular and physiological differences between dominant diatom groups and add to the growing body of evidence for Pseudo-nitzschia’s increasingly important role in warming SO ecosystems. This study also suggests that temperature-driven shifts in SO phytoplankton assemblages may increase utilization of the vast pool of excess nutrients in iron-limited SO surface waters, and thereby influence global nutrient distributions and carbon cycle.Significance StatementPhytoplankton assemblages contribute to the Southern Ocean’s ability to absorb atmospheric CO2, form the base of marine food webs, and shape the global distribution of macronutrients. Anthropogenic climate change is altering the SO environment, yet we do not fully understand how resident phytoplankton will react to this change. By comparing the responses of two prominent SO diatom groups to changes in temperature and iron in a natural community, we find that one group, Pseudo-nitzschia, grows better under warmer low-iron conditions by managing cellular iron demand and efficiently increasing photosynthetic capacity. This ability to grow and draw down nutrients in the face of warming, regardless of iron availability, may have major implications for ocean ecosystems and global nutrient and carbon cycles.

Vast and diverse microbial communities exist within the ocean. To better understand the global influence of these microorganisms on Earth’s climate, we developed a robot capable of sampling dissolved and particulate seawater biochemistry across ocean basins while still capturing the fine-scale biogeochemical processes therein. Carbon and other nutrients are acquired and released by marine microorganisms as they build and break down organic matter. The scale of the ocean makes these processes globally relevant and, at the same time, challenging to fully characterize. Microbial community composition and ocean biochemistry vary across multiple physical scales up to that of the ocean basins. Other autonomous underwater vehicles are optimized for moving continuously and, primarily, horizontally through the ocean. In contrast, Clio, the robot that we describe, is designed to efficiently and precisely move vertically through the ocean, drift laterally in a Lagrangian manner to better observe water masses, and integrate with research vessel operations to map large horizontal scales to a depth of 6000 meters. We present results that show how Clio conducts high-resolution sensor surveys and sample return missions, including a mapping of 1144 kilometers of the Sargasso Sea to a depth of 1000 meters. We further show how the samples obtain filtered biomass from seawater that enable genomic and proteomic measurements not possible through in situ sensing. These results demonstrate a robotic oceanography approach for global-scale surveys of ocean biochemistry.