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Microbial community ecology seeks to unravel the patterns and processes that govern the diversity, assembly, and functional stability of microbial assemblages across global ecosystems. In recent years, the increased availability of sequencing data from large-scale ocean microbiome projects has made it feasible to study microbial community assembly and its underlying mechanisms across global marine environments. In this study, we have investigated species richness patterns, community assembly mechanisms, and interaction patterns of marine bacterial communities by analyzing 16S ribosomal RNA amplicon sequencing data from 4,611 samples collected from ocean microbiome projects. Using neutral community models, the iCAMP framework, and co-occurrence network analyses, we showed that stochastic processes drive microbial community assembly across all latitude zones. In the polar zone, dispersal limitation was the primary driver of community assembly, compared with temperate and tropical communities, where dispersal limitation and selection played an important role. Polar microbial communities exhibited the highest modularity and network robustness, but were more vulnerable to hub removal. Although previous studies have attributed the higher stability of polar communities to environmental filtering, our analyses reveal that the resilience of the community is dependent on a few central taxa. By classifying the genera as generalists and specialists, we further highlight the role played by the specialist taxa in maintaining the stability of the marine microbial community, especially under the pressures of climate change and global warming. In general, our findings offer a latitudinal perspective on the stability of the ocean bacterial community, with implications for understanding their responses to environmental disturbances. Marine microbes play a vital role in sustaining food webs, cycling nutrients, and regulating Earth's climate. However, we still lack a global understanding of how these microbial communities form, interact, and remain stable under environmental change. By analyzing over 4,600 ocean samples from across the globe, using integrative approaches like neutral models, iCAMP, and network analysis, we have dissected the processes driving bacterial community assembly across different latitude zones and identified that the relative contributions of deterministic and stochastic processes vary significantly. This latitudinal variation in the assembly mechanisms highlights the complexity of the dynamics of the bacterial community in the ocean. Importantly, identifying the pivotal role of specialist taxa in upholding community stability underlines the vulnerability of these ecosystems to disturbances that could disrupt key microbial interactions. Understanding these microbial dynamics is critical for conserving ocean health and sustaining the processes that govern global ecosystems.

The kelp populations of two cryptic species of Lessonia inhabiting the intertidal zone of the southeastern Pacific are vulnerable to local extinction and range contraction by being exposed to large-scale thermal extremes and strong harvesting by artisanal fisheries. Our study explored the effect of variable ocean temperature conditions on the germination of spores, a critical stage for post-disturbance persistence of local populations, including harvesting. Over a 15-month experimental period, we collected reproductive tissues from 10 tagged sporophytes of a wild local population of L. spicata in Central Chile (~33.5&#xb0; S) and measured germination success. Reproductive activity closely tracked the presence of low (<14&#xb0;C) ocean temperatures at the study site. Mean spore germination was over 80% from late Austral fall to late spring and sharply declined and became more variable under the warmer ocean conditions of summer and early fall. Unexpectedly, a mid-summer mesoscale upwelling event cooled seawater below 14&#xb0;C, and spore germination success increased from <50% to up to 90%. Across the study period, germination showed a significant negative correlation with seawater temperature, down to a lag of 4&#x2009;days prior to the collection of reproductive tissue. These results suggest both a temperature threshold and a temporal scale for spore priming in L. spicata, providing support to earlier hypotheses positing spatial heterogeneity in the upwelling regime as the leading driver of speciation in the Lessonia complex. Together, our results provide an important evolutionary insight for the conservation, restocking, and management of the Lessonia complex.

Stratified vertical positioning of protocells offers evolutionary opportunities in paleo-oceans yet remains challenging achieve under prebiotic resource scarcity. Physical encounters among protocell populations are essential for molecular exchange and chemical complexity. Here, we demonstrate minimal structural variations of amphiphiles and small molecules-including isomers, alkyl-chain length, and counterion-dictate coacervate buoyancy, thereby governing vertical migration and stratification in water columns. Systematic parameter tuning produces coacervates residing in either upper or lower phases, while environmental cues like concentration and temperature dynamically modulate droplet positioning. Structural analysis reveals buoyancy arises from a sponge-like architecture composed of hydrated, flexible multilayers, with vertical positioning determined by hydration layer thickness and hydrophobic-to-hydrated layer ratio. Temperature-driven migration further induces collisions and fusion between coacervate populations, promoting molecular exchange and generating new substances. These findings suggest a physicochemical mechanism by which subtle molecular variations can encode protocell-like spatial organization, interaction frequency, and access to external energy in stratified aqueous environments.

The marine fish genera Acanthistius and Trachypoma are restricted to temperate and subtropical rocky reefs of the Southern Hemisphere, with the former comprising 11 species distributed circumglobally and the latter represented by a single species confined to the South Pacific. Both genera have been the subject of more than a century of taxonomic debate, having historically been placed in the families Anthiadidae, Epinephelidae, and Serranidae sensu stricto. Recent molecular studies have placed Acanthistius outside the aforementioned families. However, these studies relied on limited taxon sampling, leaving relationships within Acanthistius and its familial placement unresolved. Similarly, recent morphological evidence has challenged the familial placement of Trachypoma. Here, we present the most comprehensive phylogenetic analysis of Acanthistius and Trachypoma to date (eight of 11 nominal species of Acanthistius), using a combination of mitochondrial genomes and nuclear markers. Our time-calibrated phylogeny supports a monophyletic Acanthistius, with an origin in the mid Eocene to early Miocene and subsequent diversification driven by trans-oceanic dispersal. Our results agree with previous studies in placing both Acanthistius and Trachypoma outside of the Anthiadidae, Epinephelidae, and Serranidae sensu stricto. By integrating our phylogenetic results with morphological and osteological data, we formally recognise the subfamily group name Acanthistiinae and elevate it to family rank as Acanthistiidae. We also erect a new family, Trachypomatidae fam. nov., to accommodate Trachypoma.

Basidiomycetous red yeast Rhodotorula sp. is prevalent and abundant in the open ocean. This study reports the draft genomes of the Rhodotorula sp. strains HGY1 and HGY2. The strains are capable of producing carotenoids, such as &#x3b2;-carotene, and are regarded as potential hosts for biorefinery.

Visceral Kaposi's sarcoma (KS), like pulmonary KS (PKS), is more common in HIV associated/epidemic KS (EpKS). Its presentation often mimics other opportunistic pulmonary infections and is associated with poor outcomes. This study investigated the prevalence of PKS, and factors associated with overall survival at a tertiary hospital in Tanzania. This retrospective study reviewed records of 269 histologically confirmed cutaneous KS patients treated at the Ocean Road Cancer Institute between January 2019 and December 2022. Sociodemographic, clinical, and survival data were extracted from patients' files. Specialist radiologists reviewed chest radiographs taken at the time of diagnosis, categorizing them as normal, infectious infiltrates, or PKS. Data were analyzed using descriptive statistics, and Cox Proportional Hazard model identified factors linked to overall survival. Statistical significance was defined as p&#x2009;<&#x2009;0.05. Among 269 patients with cutaneous KS, 195 had EpKS, 66 had Endemic KS (EnKS), and 8 had unknown HIV status and were excluded from further analysis. The male-to-female ratio was 2:1. While all patients had cutaneous KS lesions, 23 (8.8%) had PKS which was significantly more common in the EpKS than EnKS group (p&#x2009;=&#x2009;0.024). Additionally, 24 patients (9.2%) had Chest X-ray findings (CXR) indicative of infection. At one year, overall survival was 53% for patients with PKS, compared with 87% for those without PKS. In the adjusted analysis, patients without PKS had an 86% lower risk of mortality than those with PKS (aHR&#x2009;=&#x2009;0.14; 95% CI: 0.07-0.32; P&#x2009;<&#x2009;0.001). There is high prevalence of advanced KS presentation and poor overall survival especially among PKS in SSA, despite widespread ART use. Although CXR remains the diagnostic mainstay in this setting, it is subject to notable limitations. Simple, low-cost diagnostic algorithms are needed to optimize CXR utility alongside the ongoing expansion of advanced imaging and bronchoscopic services in the region.

Fecal indicator bacteria (FIB) have historically been used to assess public health risks associated with contact water recreation, and microbial source tracking (MST) has been introduced to distinguish human-associated fecal pollution from natural sources of animal feces. While MST can identify human-associated fecal pollution, without interpretation it cannot differentiate between small amounts of fresh fecal contamination and large amounts of decayed pollution, which can present vastly different health risks. This study examined the ratio of HF183 and pepper mild mottle virus (PMMoV) as an indicator of the age of fecal contamination. The correlation was also assessed between these two individual markers, the HF183:PMMoV ratio, and two enteric viruses, norovirus genogroup II (NoV GII) and human adenovirus (HAdV). A total of 364 samples were collected under varying weather conditions over two years at impacted and reference surface water sites in southern California, including estuaries and adjacent ocean locations. The mean concentrations of MST markers and enteric viruses were higher during the rainy season compared to the dry season, especially at the impacted sites. NoV GII showed seasonality with higher detections and concentrations during the rainy season, while HAdV did not show such seasonal trends. The HF183:PMMoV ratio demonstrated a stronger correlation with enteric viruses than either marker alone, but when seasonal and weather effects were factored out, the HF183:PMMoV ratio and PMMoV had a stronger relationship with the concentration of enteric viruses. The results of this study indicate that the HF183:PMMoV ratio is a more reliable indicator of human fecal pathogens than the two individual markers by themselves. SYNOPSIS: The HF183:PMMoV ratio is a reliable and robust indicator for recreational water quality.

Anthropogenic carbon emissions are a major driver of ocean warming, with increasing consequences for marine species distributions and potential ecological interactions. This study investigates the cascading impacts of emission-driven climate change on the distributions and interspecific spatial relationships of ecologically important Cheilinus wrasses across the Indo-Pacific convergence zone. Using species distribution modelling (MaxEnt) under multiple future emission scenarios (RCP2.6-8.5 for the 2050s and 2100&#xa0;s), we project a marked divergence in habitat suitability responses. Narrow-range species, such as C. quinquecinctus, retained core habitats while expanding at their margins, resulting in a projected net habitat gain of up to 52.82%. In contrast, the wide-ranging and functionally important humphead wrasse (C. undulatus) showed persistent internal erosion within its current range, with a projected net habitat loss of up to 8.53%. These warming-associated redistributions, primarily constrained by changes in mean salinity, were accompanied by a reorganization of the potential spatial-overlap network among congeners. The potential spatial overlap between C. undulatus and the crown-of-thorns starfish (Acanthaster planci) was projected to decline modestly under future climate scenarios. Their current high range overlap (Schoener's D&#xa0;=&#xa0;0.864) declined to 0.828 under the 2050s RCP2.6 scenario and 0.826 under the 2100&#xa0;s RCP8.5 scenario. This projected reduction in potential spatial overlap may indicate a possible climate-driven predator-prey spatial mismatch, which could reduce spatial opportunities for interaction between C. undulatus and A. planci and warrants further empirical validation. Overall, our findings indicate that carbon emission pathways may reshape the broad-scale potential distribution patterns and spatial relationships of reef-associated fishes. The projected stable suitable areas, vulnerable reef regions, and potential reduced-overlap zones provide scenario-based spatial information for future conservation assessment and field validation, rather than direct spatial prioritization or policy recommendations.

A coastal lagoon is a shallow inland water body connected to the ocean with restricted inlets that receives organic matter from various sources as a land-sea transitional zone. To determine the factors driving resource utilization by crustaceans in response to the East Asian summer monsoon, we compared the stable isotopic (SI) ratios and fatty acids (FAs) of three dominant crustaceans in a coastal lagoon in Korea during the pre-monsoon, monsoon, and post-monsoon periods in 2021. Bayesian mixing models were used to evaluate the relative contributions of the five potential food sources to consumer diets. The isotopic signature displayed a significant difference in interspecific and temporal comparisons, characterized by a diet shift from phytoplankton-feeding mysid shrimp to macroalgal consumption during the monsoon period. In contrast, Palaemonidae shrimps consumed macroalgae throughout summer, and selectivity was enhanced during the monsoon period. FA profiles revealed that dinoflagellates were the dominant basal food source in crustacean feeding patterns, and macroalgal consumption by crustaceans was primarily derived from freshwater discharge when the summer monsoon event influenced the physically warm and disturbed conditions in the shallow lagoon. Additionally, we confirmed that trophic plasticity in crustaceans occurred concurrently with dinoflagellate availability during the monsoon period, as revealed by chemotaxonomic analysis of the phytoplankton community structure. The complementarity of the biomarkers allowed for a better understanding of food-web dynamics in temperate lagoons linked with East Asian monsoon events by providing qualitative and quantitative information on bottom-up processes.

Climate variability driven by North Atlantic sea surface temperatures variability through the Atlantic Multidecadal Oscillation (AMO) is known to influence climate conditions in Africa. Yet, there is a need to understand whether AMO's interannual variability modulates the risks of elevated precipitation on agriculture yields in regional Africa. Here we investigate whether a positive or negative phase of the AMO modulates the risk of cereal, fruit, and vegetable yield during high precipitation events across African regions over the past six decades. Using region-specific annual yield data and climate indicators, we assess how AMO's decadal phases interact with precipitation and affect agricultural yield in North, East, West, and Southern Africa. To our knowledge this study is unique in finding that during a negative phase of the AMO (pre-1995), high precipitation levels significantly increased the likelihood of increased cereal yield in almost all regions of Africa, yet not during the positive phase of AMO (post-1995). A negative AMO exhibited more favorable growing conditions only for cereal, not fruit or vegetable yield. These findings highlight the importance of integrating oceanic climate variability into agricultural risk assessment and planning in possibly other low-income nations.

Per- and poly-fluoroalkyl substances (hereafter PFAS) are widespread and persistent compounds that pose a threat to human and wildlife health. Wildlife monitoring is essential to understand the extent of PFAS contamination and its ecological drivers. Seabirds are good bioindicators of PFAS contamination of the marine environment, yet some areas, including the French coastlines, remain poorly covered. Here, we quantified 11 legacy PFAS in the plasma of 9 seabird species (n&#xa0;=&#xa0;340 chicks) from 30 sites along the French Atlantic and Mediterranean coasts. Linear perfluorooctanesulfonic acid was by far the most abundant PFAS. Oceanic piscivorous species (Northern gannets Morus bassanus, black-legged kittiwakes Rissa tridactyla and Scopoli's shearwaters Calonectris diomedea) had the highest PFAS concentrations compared to Larus sp. gulls and shags Gulosus aristotelis. Overall, Mediterranean seabirds had lower perfluoroalkyl sulfonic acid and higher perfluoroalkyl carboxylic acid concentrations compared to Atlantic seabirds. At a finer spatial scale, chicks sampled near estuaries had a slightly higher PFAS burden, suggesting local riverine inputs. This first large-scale survey of PFAS in French seabirds reveals substantial heterogeneity in PFAS contamination across French coastal environments. Future work should address the sources of this PFAS contamination and quantify its toxicological consequences, given that sampled chicks may be at risk based on previous avian studies reporting PFAS-related health effects.

Atmospheric deposition is a major cross-media pathway by which contaminants enter aquatic environments, with significant implications for water quality and ecosystem integrity. This review synthesizes current knowledge on the sources, atmospheric transformation processes, deposition fluxes, and ecological and human health risks of atmospheric pollutants reaching water bodies, with an emphasis on linking sources, transformations, deposition, and impacts within a unified framework. Data from the Emissions Database for Global Atmospheric Research indicate that anthropogenic emissions are the dominant source, whereas pollutant fate is strongly shaped by solar radiation-driven photochemistry, ozone oxidation, and radical-mediated heterogeneous reactions that control secondary formation and modify pollutant composition, toxicity, and deposition behavior. Although the relative contribution of atmospheric deposition varies by region and pollutant class, available evidence shows that it accounts for 40%-60% of persistent organic pollutant inputs to rivers and lakes, ~20% of dissolved organic matter inputs to lakes and marshes, 5%-12% of microplastic inputs to the oceans, and up to 24.5% of inorganic compound inputs (e.g., SOx and NOx) to rivers and lakes. Once deposited, these contaminants can drive aquatic ecotoxicity and increase human exposure through inhalation, water use, and trophic transfer, contributing to both acute effects and chronic outcomes such as cancer, reproductive disorders, and organ damage. By integrating evidence across multiple pollutant classes, this review highlights atmospheric deposition as a unifying cross-media pathway linking emissions, transformation, aquatic contamination, and risk.

Plastic pollution in oceans and marine environments is increasing, generating significant negative effects due to the widespread use of non-biodegradable polymers in marine applications such as buoys, sensors, covers, boat components, and various accessories, which often end up as marine litter. Polylactic acid (PLA), a well-known biodegradable and bio-based polymer, is increasingly being considered as a sustainable alternative to conventional plastics. However, while the marine degradation of PLA has been investigated in injection-moulded parts, films, and additively manufactured components, it remains largely unexplored in rotationally moulded structures, despite the fact that this processing method induces significant differences in material properties. In this work, PLA samples were manufactured using rotational moulding, a common method for producing hollow plastic parts, and later exposed to real marine conditions for 18&#xa0;months. Samples were extracted every three months to assess weight loss, mechanical properties, thermal stability, and hydrophobicity, and results were compared with polyethylene (PE) controls. After 18&#xa0;months, the material largely retained its mechanical properties and thermal stability, exhibiting a weight loss of approximately 1.3%, while hydrophobicity increased by nearly 40%, in line with expected hydrolytic degradation processes. Although further research is required, PLA may not entirely prevent long-term marine litter due to its low degradation rate in the marine environment; however, appropriate design and manufacturing strategies could enable controlled degradation.

Lung cancer remains to be the leading cause of cancer-related mortality worldwide, with non-small cell lung carcinoma (NSCLC) accounting for approximately 85% and the five-year survival rate below 20%. Microcolin A (Mic A), a lipopeptide derived from marine cyanobacteria, exhibits significant antitumor activity, however, its underlying mechanism is unclear. Hsp90 is highly expressed in various cancer tissues and positively correlated with tumor progression and aggressiveness. Existing studies have shown that most Hsp90 inhibitors target the N-terminal ATP-binding pockets, however, the clinical trials of the relevant candidate drugs have been halted or postponed for insufficient stratification and side effects. In contrast, targeting the C-terminal domain of Hsp90 may be a more promising route to develop the anti-cancer drug. In this study, we find that Hsp90&#x3b1; is a potential target for Mic A, which could target the C-terminal of Hsp90&#x3b1; and suppress its expression in NSCLC cells. Mic A could also induce the apoptosis of NSCLC cells through reactive oxygen species (ROS) and ERK phosphorylation pathways, and the autophagy process may also be involved in the mechanism. In the NSCLC xenograft tumor model, Mic A could significantly reduce the growth of xenograft tumors by reducing Hsp90 and upregulating ERK phosphorylation. Overall, our research provides a broader perspective for a deeper understanding of the development of anti-tumor drugs targeting Hsp90, and the mechanism of intracellular downstream signaling pathways. And the Mic A, a tool molecule derived from the ocean, could provide significant references for the future development of anti-NSCLC.

The Antarctic fur seal (Arctocephalus gazella) plays a key role in the Antarctic marine ecosystem by regulating krill, fish, and cephalopod populations through selective foraging, promoting Southern Ocean productivity via excretion, and influencing coastal island ecosystems during breeding season. Despite the importance of the gut microbiota in reflecting diet, health, and environmental adaptation, the gut microbiome of the Antarctic fur seal remains poorly characterized. To address this gap and evaluate its potential as a bioindicator of Antarctic marine environmental health, we employed shotgun metagenomics and 16S rRNA amplicon sequencing on fresh fecal samples collected from four Antarctic fur seals (designated S59, S62, S63, and S64) at King George Island, Western Antarctica. Despite inter-individual variation, both approaches identified Bacillota as the dominant phylum but showed genus-level discrepancies, with Fusobacterium prevailing in metagenomes and Clostridium in 16S amplicons. Viral communities constituted up to 5.3% of the microbiome, including an immunodeficiency-associated Lentivirus. Chitin-degrading capacity was ubiquitous, consistent with the host's krill-based diet. Metagenome-assembled genomes (MAGs) resolved distinct taxonomic contributions to discrete steps of chitin hydrolysis, suggesting that complete depolymerization requires metabolic cross-feeding among functionally complementary taxa. Notably, Helicobacter MAGs were abundant in individual S62, suggesting potential pathogenicity. Additionally, 16 antibiotic resistance gene types were detected, with bacitracin, polymyxin, and multidrug resistance dominating the resistome. These findings not only elucidate the community composition, functional potential, and ecological adaptation of the Antarctic fur seal gut microbiota but also establish a comprehensive baseline for assessing environmental change and human impacts on the Antarctic marine ecosystem, thereby offering valuable scientific data and methodological insights for the conservation of polar marine mammals.

Marine sediments serve as a major sink for persistent organic pollutants. Numerous persistent organic pollutants have been reported in sediments, but the mechanisms controlling the occurrence and behaviour of an important group of contaminants, the polyfluoroalkyl acids (PFAAs), in depositional marine environments remain poorly understood. In this study, sediment grain-size composition, grain-size descriptors, and hydrodynamic processes were integrated to investigate the environmental transport and fate of PFAAs in surface sediments of the East China Sea. Total PFAA concentrations ranged from 0.37 to 4.75&#x202f;ng/g dw. Among the 20 target PFAAs, 17 were detected in surface sediments. Perfluorooctanoic acid and perfluorooctanesulfonic acid were the most frequently detected and major compounds, with detection frequencies of 100% and 86% and maximum concentrations of 2.19 (ng/g dw) and 0.28 (ng/g dw), respectively. The long-chain PFAAs preferentially accumulated in low-energy, stable, nearshore settings. High-energy, outer-shelf environments with poor sorting and high sediment resuspension showed low long-term accumulation of PFAAs. Functional groups significantly influenced the affinity of compounds with the same carbon chain length to sediments. Perfluorooctanesulfonic acid was significantly correlated with both total organic carbon (TOC) (Spearman's &#x3c1;&#x202f;=&#x202f;0.572, p&#x202f;<&#x202f;0.001) and mud content (Spearman's &#x3c1;&#x202f;=&#x202f;0.539, p&#x202f;<&#x202f;0.01), with TOC showing a slightly stronger association under low-TOC conditions (0.2-0.6%). Spatial gradient analyses showed that PFAA concentrations decreased with increasing distance from shore, highlighting the importance of nearshore terrestrial inputs. Depositional cores identified by sediment transport trend analysis coincided with PFAA hotspots, indicating that muddy depocenters act as key regional sinks. This study suggests that contrasting depositional regimes and sediment transport processes might help explain the spatial distribution and sedimentary accumulation of PFAAs in marine sediments.