Algal blooms in the ocean: hot spots for chemically mediated microbial interactions

Nature Reviews Microbiology, Год журнала: 2023, Номер 22(3), С. 138 - 154

Опубликована: Окт. 13, 2023

Язык: Английский

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Partitioning of the denitrification pathway and other nitrite metabolisms within global oxygen deficient zones

ISME Communications, Год журнала: 2023, Номер 3(1)

Опубликована: Июль 20, 2023

Abstract Oxygen deficient zones (ODZs) account for about 30% of total oceanic fixed nitrogen loss via processes including denitrification, a microbially mediated pathway proceeding stepwise from NO3− to N2. This process may be performed entirely by complete denitrifiers capable all four enzymatic steps, but many organisms possess only partial denitrification pathways, either producing or consuming key intermediates such as the greenhouse gas N2O. Metagenomics and marker gene surveys have revealed diversity genes within ODZs, whether these co-occur identities denitrifying taxa remain open questions. We assemble genomes metagenomes spanning ETNP Arabian Sea, map metagenome-assembled (MAGs) 56 three major ODZs reveal predominance denitrifiers, particularly single-step denitrifiers. find niche differentiation among nitrogen-cycling organisms, with communities performing each transformation distinct in taxonomic identity motility traits. Our collection 962 MAGs presents largest pelagic ODZ microorganisms reveals clearer picture cycling community this environment.

Язык: Английский

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Abundant Sulfitobacter marine bacteria protect Emiliania huxleyi algae from pathogenic bacteria

ISME Communications, Год журнала: 2023, Номер 3(1)

Опубликована: Сен. 22, 2023

Emiliania huxleyi is a unicellular micro-alga that forms massive oceanic blooms and plays key roles in global biogeochemical cycles. Mounting studies demonstrate various stimulatory inhibitory influences bacteria have on the E. physiology. To investigate these algal-bacterial interactions, laboratory co-cultures been established by us others. Owing to co-cultures, mechanisms of interactions revealed, many involving bacterial pathogenicity towards algae. However, represent significantly simplified system, lacking complexity communities. In order within an ecologically relevant context, it becomes imperative enhance microbial co-culture setups. Phaeobacter inhibens are known pathogens cause death algae systems. The depend algal exudates for growth, but when senesce, switch pathogenic state induce death. Here we whether P. can presence complex community. We show huxleyi-associated community protects alga from pathogen, although pathogen occurs study how regulates pathogenicity, reduced five-member synthetic (syncom). syncom comprised single host five isolated species, which major groups naturally associated with huxleyi. discovered species community, Sulfitobacter pontiacus, pathogen. further found protection shared trait among several species. Algal might be common phenomenon ecological significance, overlooked

Язык: Английский

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Advances in understanding of air–sea exchange and cycling of greenhouse gases in the upper ocean

Elementa Science of the Anthropocene, Год журнала: 2024, Номер 12(1)

Опубликована: Янв. 1, 2024

The air–sea exchange and oceanic cycling of greenhouse gases (GHG), including carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4), monoxide (CO), nitrogen oxides (NOx = NO + NO2), are fundamental in controlling the evolution Earth’s atmospheric chemistry climate. Significant advances have been made over last 10 years understanding, instrumentation methods, as well deciphering production consumption pathways GHG upper ocean (including surface subsurface down to approximately 1000 m). global under current conditions is now established a major sink for CO2, source N2O minor both CH4 CO. importance or NOx largely unknown so far. There still considerable uncertainties about processes their drivers distributions N2O, CH4, CO, ocean. Without having understanding pathways, our knowledge effects ongoing changes—warming, acidification, deoxygenation, eutrophication—on remains rudimentary at best. We suggest that only through comprehensive, coordinated, interdisciplinary approach includes data collection by observation networks joint process studies can necessary be generated (1) identify relevant microbial phytoplankton communities, (2) quantify rates (3) comprehend drivers, (4) decipher economic cultural implications mitigation solutions.

Язык: Английский

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Microalgal multiomics-based approaches in bioremediation of hazardous contaminants

Environmental Research, Год журнала: 2024, Номер 247, С. 118135 - 118135

Опубликована: Янв. 12, 2024

Язык: Английский

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Phylogenetics and environmental distribution of nitric oxide forming nitrite reductases reveals their distinct functional and ecological roles

ISME Communications, Год журнала: 2024, Номер unknown

Опубликована: Фев. 2, 2024

Abstract The two evolutionary unrelated nitric oxide-producing nitrite reductases NirK and NirS are best known for their redundant role in denitrification. They also often found organisms that do not perform To assess the functional roles of enzymes to address sequence structural variation within each, we reconstructed robust phylogenies both proteins with sequences recovered from 6973 isolate metagenome-assembled genomes identified 32 well-supported clades structurally distinct protein lineages. We then inferred potential niche each clade by considering other genes carrying them, as well relative abundances nir gene 4082 environmental metagenomes across diverse aquatic, terrestrial, host-associated, engineered biomes. demonstrate Nir recapitulate ecology distinctly corresponding organismal phylogeny. While some reductase were equally prevalent biomes, others had more restricted ranges. Nitrifiers make up a sizeable proportion reducing community, especially marine surface waters dry soils. Furthermore, showed associations involved oxidising compounds, indicating activity may be linked different elemental cycles. Accordingly, abundance diversity vs. varies between Our results show divergent ecological NirS-encoding play environment provide phylogenetic framework distinguish traits associated encoding lineages reductases.

Язык: Английский

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Bacteria contribute exopolysaccharides to an algal-bacterial joint extracellular matrix

npj Biofilms and Microbiomes, Год журнала: 2024, Номер 10(1)

Опубликована: Апрель 1, 2024

Abstract Marine ecosystems are influenced by phytoplankton aggregation, which affects processes like marine snow formation and harmful events such as mucilage outbreaks. Phytoplankton secrete exopolymers, creating an extracellular matrix (ECM) that promotes particle aggregation. This ECM attracts heterotrophic bacteria, providing a nutrient-rich protective environment. In terrestrial environments, bacterial colonization near primary producers relies on attachment the of multidimensional structures biofilms. Bacteria were observed attaching aggregating within algal-derived but it is unclear if bacteria produce contributes to this colonization. study, using Emiliania huxleyi algae Phaeobacter inhibens in environmentally relevant model system, reveals shared algal-bacterial scaffold Algal exudates play pivotal role promoting colonization, stimulating exopolysaccharide (EPS) production, facilitating joint formation. A biosynthetic pathway responsible for producing specific EPS contributing identified. Genes from show increased expression algal-rich environments. These findings highlight underestimated aggregate-mediated offering insights into interactions formation, with implications understanding managing natural perturbed aggregation events.

Язык: Английский

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Protists play important roles in the assembly and stability of denitrifying bacterial communities in copper-tailings drainage

The Science of The Total Environment, Год журнала: 2024, Номер 917, С. 170386 - 170386

Опубликована: Янв. 26, 2024

Язык: Английский

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Phycospheric Bacteria Alleviate the Stress of Erythromycin on Auxenochlorella pyrenoidosa by Regulating Nitrogen Metabolism

Plants, Год журнала: 2025, Номер 14(1), С. 121 - 121

Опубликована: Янв. 3, 2025

Macrolide pollution has attracted a great deal of attention because its ecotoxic effects on microalgae, but the role phycospheric bacteria under antibiotic stress remains unclear. This study explored toxic erythromycin (ERY) growth and nitrogen metabolism Auxenochlorella pyrenoidosa; then, it analyzed predicted composition ecological function microalgae ERY stress. We found that 0.1, 1.0, 10 mg/L inhibited chlorophyll gradually showed enhanced abilities over course 21 days. As exposure time progressed, nitrate reductase activities increased, remained significantly lower than control group at d. NO3− concentrations in all treatment groups decreased were consistent with growth. NO2− three those during changed community diversity bacteria. The relative abundance bacteria, such as unclassified-f-Rhizobiaceae, Mesorhizobium, Sphingopyxis, Aquimonas, Blastomonas, varied to different degrees. Metabolic functions, ABC transporters, microbial diverse environments, biosynthesis amino acids, upregulated treatments higher (1.0 mg/L). Higher denitrification, nitrous oxide nitrite respiration. findings this suggest alleviate restore by regulating system.

Язык: Английский

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Nitric oxide release as a defense mechanism in marine microalgae against microplastic-induced stress

Environmental Pollution, Год журнала: 2025, Номер 367, С. 125668 - 125668

Опубликована: Янв. 11, 2025

Язык: Английский

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