Distinct bacterial succession and functional response to alginate in the South, Equatorial, and North Pacific Ocean

Environmental Microbiology, Journal Year: 2024, Volume and Issue: 26(3)

Published: Feb. 28, 2024

Abstract The availability of alginate, an abundant macroalgal polysaccharide, induces compositional and functional responses among marine microbes, but these dynamics have not been characterized across the Pacific Ocean. We investigated alginate‐induced shifts (e.g., heterotrophic production, glucose turnover, hydrolytic enzyme activities) microbial communities in South Subtropical, Equatorial, Polar Frontal North mesocosms. observed that response to alginate were site‐specific. In Subtropical Pacific, prokaryotic cell counts, peptidase activities changed most with addition, along enrichment widest range particle‐associated taxa (161 amplicon sequence variants; ASVs) belonging Alteromonadaceae , Rhodobacteraceae Phormidiaceae Pseudoalteromonadaceae . Some detected at other sites only enriched Pacific. Equatorial turnover production increased rapidly; a single Alteromonas taxon dominated (60% community) remained low (<2%) elsewhere. community was gradual, more limited alginate‐enriched (82 ASVs). Thus, alginate‐related ecological biogeochemical depend on combination factors include ability utilize environmental conditions, interactions.

Language: Английский

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Estimating taxonomic and functional structure along a tropical estuary: linking metabolic traits and aspects of ecosystem functioning

Microbiology Spectrum, Journal Year: 2024, Volume and Issue: 12(10)

Published: Aug. 20, 2024

ABSTRACT Microbial life forms are among the most ubiquitous on Earth, yet many remain understudied in Caribbean estuaries. We report prokaryote community composition of Urabá Estuary Colombian using 16S rRNA gene-transcript sequencing. also assessed potential functional diversity through 38 metabolic traits inferred from gene data. Water samples were collected six sampling stations at two depths with contrasting light-penetration conditions along an approximately 100 km transect Gulf December 2019. Non-metric multidimensional scaling analysis grouped into distinct clusters and between depths. The primary variables influencing station, depth, salinity, dissolved oxygen levels. Twenty percent genera (i.e., 58 out 285) account for 95% differences groups All studied showed some significant relationship tested environmental variables, especially salinity except temperature. Another non-metric analysis, based community-weighted mean traits, over depth. Biodiversity facets, such as richness, evenness, redundancy, indicated that variations—stemming river discharges—introduce imbalance surface communities closer to estuary’s head bottom ocean. Our research broadens use transcripts beyond mere taxonomic assignments, furthering field trait-based ecology transitional aquatic ecosystems. IMPORTANCE resilience a dynamic ecosystem is directly tied ability its microbes navigate gradients. This study delves changes within (Colombian Caribbean) first time. integrate data (taxonomic functional) variability gain understanding this under-researched multi-faceted macroecological framework. found shifts influenced by physical-chemical fluctuations across gradient. Furthermore, we identified disparity diversity. Near-surface exhibited compared deeper situated farther away. serves roadmap posing new inquiries about highly ecosystems, pushing forward domain multi-trait-based ecology.

Language: Английский

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The surface bacterial community of an Australian kelp shows cross-continental variation and relative stability within regions

FEMS Microbiology Ecology, Journal Year: 2021, Volume and Issue: 97(7)

Published: June 18, 2021

Abstract Epiphytic microbial communities often have a close relationship with their eukaryotic host, assisting defence, health, disease prevention and nutrient transfer. Shifts in the structure of could therefore negative effects on individual host indirectly impact surrounding ecosystem, particularly for major habitat-forming hosts, such as kelps temperate rocky shores. Thus, an understanding dynamics host-associated is essential monitoring assessing ecosystem changes. Here, samples were taken from ecologically important kelp, Ecklonia radiata, over 17-month period, six different sites two distinct geographic regions (East West coasts Australia), separated by ∼3,300 kms, to understand variation kelp bacterial community its potential environmental drivers. Differences observed between largely disconnected geographical regions. In contrast, within each region time considerably more stable, despite substantial seasonal changes conditions.

Language: Английский

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Extensive Microbial Processing of Polysaccharides in the South Pacific Gyre via Selfish Uptake and Extracellular Hydrolysis

Frontiers in Microbiology, Journal Year: 2020, Volume and Issue: 11

Published: Dec. 18, 2020

Primary productivity occurs throughout the deep euphotic zone of oligotrophic South Pacific Gyre (SPG), fueled largely by regeneration nutrients and thus recycling organic matter. We investigated heterotrophic capabilities SPG's bacterial communities examining their ability to process polysaccharides, an important component marine focused on initial step matter degradation measuring activities extracellular enzymes that hydrolyze six different polysaccharides smaller sizes. This can occur two distinct mechanisms: "selfish uptake," in which hydrolysis is coupled transport large polysaccharide fragments into periplasmic space bacteria, with little no loss products external environment, "external hydrolysis," low molecular weight (LMW) are produced environment. Given nature SPG, we did not expect high enzymatic activity; however, found all were hydrolyzed externally taken up selfishly central observations may be linked a comparatively abundance diatoms at depth location sampled (75 m). At edge gyre close center gyre, four hydrolyzed, lower fraction community showed selfish uptake. One (fucoidan) was without measurable stations. Additional incubations water from depths 1,250 2,800 m laminarin (an abundant ocean) led extreme growth opportunistic bacteria (

Language: Английский

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Disentangle genus microdiversity within a complex microbial community by using a multi‐distance long‐read binning method: example of Candidatus Accumulibacter

Environmental Microbiology, Journal Year: 2022, Volume and Issue: 24(4), P. 2136 - 2156

Published: March 22, 2022

Summary Complete genomes can be recovered from metagenomes by assembling and binning DNA sequences into metagenome assembled (MAGs). Yet, the presence of microdiversity hamper assembly processes, possibly yielding chimeric, highly fragmented incomplete genomes. Here, four samples aerobic granular sludge bioreactors containing Candidatus ( Ca .) Accumulibacter, a phosphate‐accumulating organism interest for wastewater treatment, were sequenced with both PacBio Illumina. Different strategies genome investigated, including published protocols procedure adapted to long contigs (MuLoBiSC). Multiple criteria considered select best strategy . whose multiple strains in every sample represent challenging microdiversity. In this case, relies on long‐read only custom MuLoBiSC metaWRAP. Several high‐quality Accumulibacter MAGs, novel species, obtained independently different samples. Comparative genomic analysis showed that MAGs retrieved harbour rearrangements addition accumulation point mutations. The likely driven mobile genetic elements, causes major difficulties recovering but it is also hallmark panmictic lifestyle these bacteria.

Language: Английский

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