Increased Nutrient Levels Enhance Bacterial Exopolysaccharides Production in the Context of Algae

Environmental Microbiology Reports, Год журнала: 2025, Номер 17(1)

Опубликована: Фев. 1, 2025

ABSTRACT Microbial aggregation is central in environmental processes, such as marine snow and harmful mucilage events. Nutrient enrichment positively correlates with microbial aggregation. This correlation largely attributed to the overgrowth of microalgae overproduction agglomerating exopolysaccharides. However, recent studies highlight significant contribution bacterial exopolysaccharides algal‐bacterial Here, using controlled laboratory experiments metatranscriptomic analysis, we investigate impact nutrient on production, while bacteria are context their algal hosts. Our findings demonstrate a marked increase production response relative inorganic phosphorus nitrogen levels, both lab environment. These results interplay between regimes, physiology ecosystems emphasise gaps our understanding regarding role processes that involve

Язык: Английский

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Illuminating microalgal biofilms using advanced photonic imaging techniques

Algal Research, Год журнала: 2025, Номер unknown, С. 104018 - 104018

Опубликована: Март 1, 2025

Язык: Английский

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Metagenomics and plant-microbe symbioses: Microbial community dynamics, functional roles in carbon sequestration, nitrogen transformation, sulfur and phosphorus mobilization for sustainable soil health

Biotechnology Advances, Год журнала: 2025, Номер 82, С. 108580 - 108580

Опубликована: Апрель 15, 2025

Язык: Английский

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The bacterial Bmt methionine synthase is involved in lag phase shortening

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Июнь 21, 2024

Abstract Bacteria can shorten their lag phase by utilizing methyl groups from compounds such as dimethylsulfoniopropionate (DMSP). These are then incorporated into cellular building blocks via the methionine cycle. However, specific contribution of bacterial synthesis, which is critical for assimilating and incorporating groups, remains unclear. In this study, we employed transcriptomics, genetic manipulation biochemical assays to explore involvement synthesis in shortening using model marine bacterium Phaeobacter inhibens . We mapped expression profiles MetH-like synthase components—an enzyme complex that encoded three genes—in response DMSP during phase. Our findings revealed transcriptional decoupling genes. The deletion homocysteine-binding component complex, namely bmt , disrupted DMSP. Through heterologous gene product, show individual Bmt produces directly demethylating betaine vitro reveal a metabolic route was not previously described bacteria. Since does require tetrahydrofolate or cobalamin co-factors its potential act alone demethylase represents cost-effective shortcut group assimilation, could be specifically beneficial under limiting conditions. Indeed, stress conditions, allows cells This study enhances our understanding enzymatic mechanisms underlying shortening, revealing microbial adaptation strategies environmental

Язык: Английский

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Sanitization of hydroponic farming facilities in Singapore: what, why, and how

Applied and Environmental Microbiology, Год журнала: 2024, Номер 90(7)

Опубликована: Июль 24, 2024

ABSTRACT This study performed microbial analysis of nutrient film technique (NFT) hydroponic systems on three indoor farms in Singapore (the “what”). To justify the necessity sanitizing systems, strong biofilm-forming bacteria were isolated from facility and investigated for their influence Salmonella colonization polyvinyl chloride (PVC) coupons solutions “why”). Finally, sanitization evaluated with both laboratory-scale field-scale tests “how”). As a result, microbiome composition NFT was found to be highly farm specific. The biofilm formers Corynebacterium tuberculostearicum C2 Pseudoxanthomonas mexicana C3 facilitate attachment PVC coupons. When forming dual-species biofilms, presence also significantly promoted growth ( P < 0.05). Compared hydrogen peroxide (H 2 O ) sodium percarbonate (SPC), hypochlorite (NaOCl) exhibited superior efficacy removal. At 50 ppm, NaOCl reduced Typhimurium, C2, counts <1 log CFU/cm within 12 h, whereas neither 3% H nor 1% SPC achieved this effect. In operational concentration needed achieve elimination increased 500 likely due organic matter accumulated during crop cultivation greater persistence naturally formed multispecies biofilms. Sanitization using ppm h did not impede subsequent plant growth, but chlorination byproduct chlorate detected at high levels solution plants sanitized without rinsing. IMPORTANCE study’s significance lies first its elucidation farming systems. although mostly nonpathogenic, might serve as hotbed pathogen thus pose risk food safety. We explored tests. Of tested sanitizers, most effective economical option, one must note vital importance rinsing after NaOCl.

Язык: Английский

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Algal exudates promote conjugation in marine Roseobacters

mBio, Год журнала: 2024, Номер 15(10)

Опубликована: Авг. 27, 2024

Horizontal gene transfer (HGT) is a pivotal mechanism driving bacterial evolution, conferring adaptability within dynamic marine ecosystems. Among HGT mechanisms, conjugation mediated by type IV secretion systems (T4SSs) plays central role in the ecological success of bacteria. However, conditions promoting events environment are not well-understood. Roseobacters, abundant bacteria commonly associated with algae, possess multitude T4SSs. Many Roseobacters heterotrophic that rely on algal secreted compounds to support their growth. These attract bacteria, facilitating colonization and attachment cells. Algae metabolites bring into close proximity, potentially HGT. Investigation across various revealed exudates indeed enhance plasmid through conjugation. While do influence transcription conjugative machinery genes, they promote attachment, stabilizing proximity Notably, under where less advantageous, impact reduced. findings suggest algae primarily fostering highlight importance studying context algal-bacterial interactions.

Язык: Английский

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Spirulina-Based Multispecies Phototrophic Biofilm Anodic Biocatalyst Endures a Prolonged Dark Phase within Light–Dark Cycle Operations and Enhances Anodic Performance in Biophotovoltaic Cells

ACS ES&T Engineering, Год журнала: 2024, Номер unknown

Опубликована: Окт. 15, 2024

Phototrophs with heterotrophic bacterial consortium as an electrode biocatalyst are emerging concept for developing naturally sustained biophotovoltaic systems. Herein, Spirulina subsalsa-based mixed community anodic catalyst in a microbial fuel cell (MFC) setup ferricyanide catholyte 78 days light–dark (16–8 h) cycle-based operation was investigated. The biofilm developed inducted recalcitrant comprising Halomonas, Alcanivorax, Pelagibacterium, and Rhizobiales the major genera. In extended dark phase (9 days) within cyclic operation, sequential shift of metabolism from photosynthesis to fermentative states increased population were observed. Under direct contact graphite anode, initiated oscillating open-circuit potentials MFC response circadian trend. delivered maxima 587 μW m–2 418 (at 10 kΩ) under corresponding phases, respectively. potential shifted more negative value, reaching −415.5 mV starvation period. Analyses reaction rates (extracted Tafel plots), corrosion potential, current, polarization resistance, residual redox charges voltammograms) performed understand processes. Two peaks 0.6 V (irreversible, extracellular) 0.26 (reversible, cell-surface attached) attributed mediation this process. Additionally, catholyte-diffused interacts biofilm, getting trapped matrix polymeric structures, thus preventing sudden cytotoxic elimination cells promoting oxidative charge accumulation over its surface, improving potential. Rapid respiratory oxygen consumption, biofilm's structural reorganization, ferricyanide's chemical speciation inside primary factors that govern performance biofuel during prolonged operations. critical findings unveiled through study advance our understanding resilience phototroph-based multispecies catalysts devices long-term

Язык: Английский

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Algal Exudates Promote Conjugation in Marine Roseobacters

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Ноя. 14, 2023

Abstract Horizontal gene transfer (HGT) is a pivotal mechanism driving bacterial evolution, conferring adaptability within dynamic marine ecosystems. Among HGT mechanisms, conjugation mediated by type IV secretion systems (T4SSs) plays central role in the ecological success of bacteria. However, conditions promoting events environment are not well understood. Roseobacters, abundant bacteria commonly associated with algae, possess multitude T4SSs. Many Roseobacters heterotrophic that rely on algal secreted compounds to support their growth. These attract bacteria, facilitating colonization and attachment cells. Algae metabolites bring into close proximity, potentially HGT. Investigation across various revealed exudates indeed enhance plasmid through conjugation. While do influence transcription conjugative machinery genes, they promote attachment, stabilizing proximity Notably, under where less advantageous, impact reduced. findings suggest algae primarily fostering highlight importance studying context algal-bacterial interactions.

Язык: Английский

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