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1.
Sci Adv ; 10(33): eadl0534, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39151014

RESUMEN

Carbon fixation is a key metabolic function shaping marine life, but the underlying taxonomic and functional diversity involved is only partially understood. Using metagenomic resources targeted at marine piconanoplankton, we provide a reproducible machine learning framework to derive the potential biogeography of genomic functions through the multi-output regression of gene read counts on environmental climatologies. Leveraging the Marine Atlas of Tara Oceans Unigenes, we investigate the genomic potential of primary production in the global ocean. The latter is performed by ribulose-1,5-bisphosphate carboxylase/oxygenase (RUBISCO) and is often associated with carbon concentration mechanisms in piconanoplankton, major marine unicellular photosynthetic organisms. We show that the genomic potential supporting C4 enzymes and RUBISCO exhibits strong functional redundancy and important affinity toward tropical oligotrophic waters. This redundancy is taxonomically structured by the dominance of Mamiellophyceae and Prymnesiophyceae in mid and high latitudes. These findings enhance our understanding of the relationship between functional and taxonomic diversity of microorganisms and environmental drivers of key biogeochemical cycles.


Asunto(s)
Fotosíntesis , Ribulosa-Bifosfato Carboxilasa , Fotosíntesis/genética , Ribulosa-Bifosfato Carboxilasa/genética , Ribulosa-Bifosfato Carboxilasa/metabolismo , Plancton/genética , Plancton/metabolismo , Genómica/métodos , Filogenia , Ciclo del Carbono , Metagenómica/métodos , Metagenoma , Agua de Mar
2.
Biofouling ; 40(8): 499-513, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39108059

RESUMEN

The bacterial community from a cooling water system was investigated through culture-dependent and independent strategies, and the responses of planktonic and sessile bacteria (grown in glass slides and stainless-steel coupons) to antimicrobials of industrial and clinical use were assessed. The morphotypes with higher biofilm-forming potential were Pseudoxanthomonas sp., Rheinheimera sp., Aeromonas sp. and Staphylococcus sp., and the first also exhibited lower susceptibility to all antibiotics and biocides tested. 16S rRNA high throughput sequencing indicated that Pseudomonadota (77.1% on average, sd 11.1%), Bacteroidota (8.4, sd 5.7%), and Planctomycetota (3.0, sd 1.3%) were the most abundant phyla. KEGG orthologs associated with antibiotics and biocide resistance were abundant in all samples. Although the minimum inhibitory and bactericidal concentrations were generally higher for biofilms, morphotypes in planktonic form also showed high levels of resistance, which could be associated with biofilm cells passing into the planktonic phase. Overall, monochloramine was the most effective biocide.


Asunto(s)
Bacterias , Biopelículas , Microbiota , Plancton , Biopelículas/efectos de los fármacos , Plancton/efectos de los fármacos , Microbiota/efectos de los fármacos , Bacterias/efectos de los fármacos , Bacterias/clasificación , Bacterias/genética , ARN Ribosómico 16S/genética , Desinfectantes/farmacología , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Microbiología del Agua
3.
Proc Natl Acad Sci U S A ; 121(35): e2407876121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39159378

RESUMEN

Coevolution between predator and prey plays a central role in shaping the pelagic realm and may have significant implications for marine ecosystems and nutrient cycling dynamics. The siliceous diatom frustule is often assumed to have coevolved with the silica-lined teeth of copepods, but empirical evidence of how this relationship drives natural selection and evolution is still lacking. Here, we show that feeding on diatoms causes significant wear and tear on copepod teeth and that this leads to copepods becoming selective feeders. Teeth from copepods feeding on thick-shelled diatoms were more likely to be broken or cracked than those feeding on a dinoflagellate. When fed a large diatom, all analyzed teeth had visible wear. Our results underscore the importance of the predator-prey arms race as a driving force in planktonic evolution and diversity.


Asunto(s)
Evolución Biológica , Copépodos , Diatomeas , Plancton , Animales , Copépodos/fisiología , Plancton/fisiología , Conducta Predatoria/fisiología , Ecosistema , Dióxido de Silicio , Diente
4.
Microb Pathog ; 193: 106774, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38969184

RESUMEN

The increasing prevalence of extensively drug-and pan-drug-resistant Pseudomonas aeruginosa is a major concern for global public health. Therefore, it is crucial to develop novel antimicrobials that specifically target P. aeruginosa and its biofilms. In the present study, we determined that berberine hydrochloride inhibited the growth of planktonic bacteria as well as prevented the formation of biofilms. Moreover, we observed downregulation in the expression of pslA and pelA biofilm-related genes. Compared with existing antibiotics, berberine hydrochloride exhibits multiple modes of action against P. aeruginosa. Our findings suggest that berberine hydrochloride exerts its antimicrobial effects by damaging bacterial cell membranes, generating reactive oxygen species (ROS), and reducing intracellular adenosine triphosphate (ATP) levels. Furthermore, berberine hydrochloride showed minimal cytotoxicity and reduced susceptibility to drug resistance. In a mouse model of peritonitis, it significantly inhibited the growth of P. aeruginosa and exhibited a strong bacteriostatic action. In conclusion, berberine hydrochloride is a safe and effective antibacterial agent that inhibits the growth of P. aeruginosa.


Asunto(s)
Adenosina Trifosfato , Antibacterianos , Berberina , Biopelículas , Modelos Animales de Enfermedad , Pruebas de Sensibilidad Microbiana , Plancton , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Especies Reactivas de Oxígeno , Berberina/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Animales , Ratones , Antibacterianos/farmacología , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Adenosina Trifosfato/metabolismo , Plancton/efectos de los fármacos , Peritonitis/microbiología , Peritonitis/tratamiento farmacológico , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
5.
Microb Pathog ; 193: 106780, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38969189

RESUMEN

This study was designed to assess the possibility of using bacteriophage-encoded endolysins for controlling planktonic and biofilm cells. The endolysins, LysEP114 and LysEP135, were obtained from plasmid vectors containing the endolysin genes derived from Escherichia coli phages. The high identity (>96 %) was observed between LysEP114 and LysEP135. LysEP114 and LysEP135 were characterized by pH, thermal, and lactic acid stability, lytic spectrum, antibacterial activity, and biofilm eradication. The molecular masses of LysEP114 and LysEP135 were 18.2 kDa, identified as muramidases. LysEP114 and LysEP135 showed high lytic activity against the outer membrane-permeabilized E. coli KCCM 40405 at below 37 °C, between pH 5 to 11, and below 70 mM of lactic acid. LysEP114 and LysEP135 showed the broad rang of lytic activity against E. coli KACC 10115, S. Typhimurium KCCM 40253, S. Typhimurium CCARM 8009, tetracycline-resistant S. Typhimurium, polymyxin B-resistant S. Typhimurium, chloramphenicol-resistant S. Typhimurium, K. pneumoniae ATCC 23357, K. pneumoniae CCARM 10237, and Shigella boydii KACC 10792. LysEP114 and LysEP135 effectively reduced the numbers of planktonic E. coli KCCM by 1.7 and 2.1 log, respectively, when treated with 50 mM lactic acid. The numbers of biofilm cells were reduced from 7.3 to 4.1 log CFU/ml and 2.2 log CFU/ml, respectively, when treated with LysEP114- and LysEP135 in the presence of 50 mM lactic acid. The results suggest that the endolysins in combination with lactic acid could be potential alternative therapeutic agents for controlling planktonic and biofilm cells.


Asunto(s)
Antibacterianos , Biopelículas , Endopeptidasas , Escherichia coli , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Endopeptidasas/farmacología , Endopeptidasas/genética , Endopeptidasas/metabolismo , Antibacterianos/farmacología , Concentración de Iones de Hidrógeno , Plancton/efectos de los fármacos , Plancton/virología , Colifagos/genética , Colifagos/fisiología , Ácido Láctico/farmacología , Bacteriófagos/genética , Temperatura , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Proteínas Virales/genética , Proteínas Virales/farmacología , Proteínas Virales/metabolismo
6.
Sci Total Environ ; 946: 174403, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38960198

RESUMEN

Conventional plastics have become a major environmental concern due to their persistence and accumulation in marine ecosystems. The development of potential degradable polymers (PBP), such as polyhydroxyalkanoates (PHAs) and polylactic acid (PLA), has gained attention as an alternative to mitigate plastic pollution, since they have the potential to biodegrade under certain conditions, and their production is increasing as replacement of conventional polyolefins. This study aimed to assess and compare the toxicity of leachates of pre-compounding PBP (PLA and the PHA, polyhydroxybutyrate-covalerate (PHBv)) and polypropylene (PP) on five marine planktonic species. A battery of standard bioassays using bacteria, microalgae, sea urchin embryos, mussel embryos and copepod nauplii was conducted to assess the toxicity of leachates from those polymers. Additionally, the presence of chemical additives in the leachates was also verified through GC-MS and LC-HRMS analysis. Results showed that PHBv leachates exhibited higher toxicity compared to other polymers, with the microalgae Rhodomonas salina, being the most sensitive species to the tested leachates. On the other hand, PP and PLA generally displayed minimal to no toxicity in the studied species. Estimated species sensitivity distribution curves (SSD) show that PHBv leachates can be 10 times more hazardous to marine plankton than PP or PLA leachates, as demonstrated by the calculated Hazardous Concentration for 5 % of species (HC5). Qualitative chemical analysis supports the toxicological results, with 80 % of compounds being identified in PHBv leachates of which 2,4,6-trichlorophenol is worth mentioning due to the deleterious effects to aquatic biota described in literature. These findings underscore the fact that whereas environmental persistence can be targeted using PBP, the issue of chemical safety remains unsolved by some alternatives, such as PHBv. Gaining a comprehensive understanding of the toxicity profiles of PBP materials through a priori toxicological risk assessment is vital for their responsible application as alternatives to conventional plastics.


Asunto(s)
Plancton , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/toxicidad , Plancton/efectos de los fármacos , Animales , Polímeros/toxicidad , Poliésteres/toxicidad , Pruebas de Toxicidad Aguda , Organismos Acuáticos/efectos de los fármacos , Biodegradación Ambiental
7.
Sci Total Environ ; 947: 174666, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38992378

RESUMEN

Planktonic communities in aquatic ecosystems are crucial water quality indicators, with their growth dependent on runoff chemical and hydraulic characteristics (e.g., nutrient availability and turbidity). Previous studies have indicated that runoff components (i.e., proportions of precipitation, groundwater, snowmelt, etc.) play a vital role in regulating runoff characteristics, potentially affecting planktonic communities. However, the response of these communities to runoff components, particularly in mountainous regions, remains underexplored. In this study, we conducted four sampling campaigns from 2017 to 2020 in a watershed on the Qinghai-Tibet Plateau. Combined with laboratory incubation experiments, we examined the impact of various runoff components on the diversity and abundance of phytoplankton and zooplankton. We found that a higher proportion of precipitation in runoff contributed to an increase in the diversity of plankton communities. Laboratory experiments with unified water samples incubated with different runoff components demonstrated that the significant influence of precipitation on planktonic diversity primarily stems from the influx of abundant exogenous particulate material into rivers. Using a path analysis, we further confirmed that the impact of precipitation on diversity is primarily through chemical pathways, notably by increasing nutrient concentrations. Our study enhances our understanding of the interactions between the hydrological cycle and aquatic ecosystems, offering valuable insights for effectively maintaining and managing these natural environments.


Asunto(s)
Biodiversidad , Plancton , Tibet , Monitoreo del Ambiente , Lluvia , Zooplancton , Fitoplancton , Ecosistema
8.
Sci Rep ; 14(1): 16298, 2024 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009635

RESUMEN

Harmful algae blooms are a rare phenomenon in rivers but seem to increase with climate change and river regulation. To understand the controlling factors of cyanobacteria blooms that occurred between 2017 and 2020 over long stretches (> 250 km) of the regulated Moselle River in Western Europe, we measured physico-chemical and biological variables and compared those with a long-term dataset (1997-2016). Cyanobacteria (Microcystis) dominated the phytoplankton community in the late summers of 2017-2020 (cyano-period) with up to 110 µg Chlorophyll-a/L, but had not been observed in the river in the previous 20 years. From June to September, the average discharge in the Moselle was reduced to 69-76% and water temperature was 0.9-1.8 °C higher compared to the reference period. Nitrogen (N), phosphorus (P) and silica (Si) declined since 1997, albeit total nutrient concentrations remained above limiting conditions in the study period. Cyanobacterial blooms correlated best with low discharge, high water temperature and low nitrate. We conclude that the recent cyanobacteria blooms have been caused by dry and warm weather resulting in low flow conditions and warm water temperature in the regulated Moselle. Under current climate projections, the Moselle may serve as an example for the future of regulated temperate rivers.


Asunto(s)
Cambio Climático , Cianobacterias , Ríos , Ríos/microbiología , Cianobacterias/crecimiento & desarrollo , Temperatura , Fitoplancton/crecimiento & desarrollo , Estaciones del Año , Fósforo/análisis , Nitrógeno/análisis , Clorofila A/análisis , Clorofila/análisis , Floraciones de Algas Nocivas , Plancton/crecimiento & desarrollo , Eutrofización , Monitoreo del Ambiente/métodos
9.
Environ Microbiol ; 26(7): e16675, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39022885

RESUMEN

Heterotrophic microbial communities play a significant role in driving carbon fluxes in marine ecosystems. Despite their importance, these communities remain understudied in remote polar oceans, which are known for their substantial contribution to the biological drawdown of atmospheric carbon dioxide. Our research focused on understanding the environmental factors and genetic makeup of key bacterial players involved in carbon remineralization in the Weddell Sea, including its coastal polynyas. Our experiments demonstrated that the combination of labile organic matter supply and temperature increase synergistically boosted bacterial growth. This suggests that, besides low seawater temperature, carbon limitation also hinders heterotrophic bacterial activity. Through the analysis of metagenome-assembled genomes, we discovered distinct genomic adaptation strategies in Bacteroidia and Gammaproteobacteria, both of which respond to organic matter. Both natural phytoplankton blooms and experimental addition of organic matter favoured Bacteroidia, which possess a large number of gene copies and a wide range of functional membrane transporters, glycoside hydrolases, and aminopeptidases. In contrast, the genomes of organic-matter-responsive Gammaproteobacteria were characterized by high densities of transcriptional regulators and transporters. Our findings suggest that bacterioplankton in the Weddell Sea, which respond to organic matter, employ metabolic strategies similar to those of their counterparts in temperate oceans. These strategies enable efficient growth at extremely low seawater temperatures, provided that organic carbon limitation is alleviated.


Asunto(s)
Gammaproteobacteria , Fitoplancton , Agua de Mar , Agua de Mar/microbiología , Regiones Antárticas , Gammaproteobacteria/metabolismo , Gammaproteobacteria/genética , Fitoplancton/metabolismo , Fitoplancton/genética , Carbono/metabolismo , Microbiota , Plancton/metabolismo , Plancton/genética , Plancton/crecimiento & desarrollo , Metagenoma , Ecosistema , Bacteroidetes/genética , Bacteroidetes/metabolismo , Bacteroidetes/crecimiento & desarrollo , Temperatura
10.
Huan Jing Ke Xue ; 45(7): 3983-3994, 2024 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-39022946

RESUMEN

In order to understand the stability of the zooplankton and phytoplankton communities in the Guizhou plateau reservoir environment, the process of reservoir water quality change affecting the stability of plankton was studied. The changes in the plankton community and water quality in three different nutrient reservoirs (Huaxi Reservoir, Goupitan Reservoir, and Hailong Reservoir) were studied from October 2020 to August 2021. The stability of the zooplankton and phytoplankton communities was studied using time-lag analysis (TLA). Variance decomposition analysis (VPA) was used to explore the response of the two communities to environmental changes. The driving factors of plankton community changes in reservoirs were also revealed. The results showed that Huaxi Reservoir and Goupitan Reservoir were mesotrophic reservoirs, and Hailong Reservoir was a eutrophic reservoir. The average comprehensive nutrition indices of the three reservoirs were 44.07, 44.68, and 50.25. A total of 51 species of zooplankton rotifers, 39 species of rotifers, three species of copepods, and nine species of cladocera were identified. Among them, the abundance of rotifers was the highest, accounting for 85.96%. A total of seven phyla and 73 species of phytoplankton were identified, including 16 species in the phylum Cyanophyta, 32 species in the phylum Chlorophyta, 16 species in the phylum Diatoma, three species in the phylum Chlorophyta, four species in the phylum Euglenophyta, and one species each in the phyla Cryptophyta and Chrysophyta. Among them, the abundance of cyanobacteria and diatoms was the highest, accounting for 66.2% and 27.35%, respectively. The median absolute deviation (MAD) of the Bray-Curtis distance of zooplankton and phytoplankton community in the three reservoirs were 0.67 and 0.65 in Huaxi Reservoir, 0.80 and 0.69 in Goupitan Reservoir, and 0.85 and 0.47 in Hailong Reservoir, respectively. The larger the value, the greater the variation in the community. The absolute value of the slope of zooplankton was greater than that of phytoplankton in the TLA results, and the absolute values of the slopes were 0.018 and 0.004, respectively. The larger the absolute value of the slope, the faster the community variability. The zooplankton community in the three reservoirs was less stable than the phytoplankton community and more sensitive to environmental changes, and the degree of variation was greater. The higher the degree of eutrophication of the reservoir, the more obvious this phenomenon. VPA showed that the changes in plankton communities in Huaxi Reservoir and Hailong Reservoir were mainly influenced by water temperature and eutrophication factors. The changes in planktonic community in Goupitan Reservoir were mainly influenced by water temperature and chemical factors. The driving factors of Huaxi Reservoir were water temperature, TP, permanganate index, and SD. The driving factors of Goupitan Reservoir were water temperature, NO3-- N, and pH. The driving factors of Hailong Reservoir were water temperature and TP. Nutrients and water temperature were the main factors affecting the stability of plankton communities in reservoirs.


Asunto(s)
Monitoreo del Ambiente , Fitoplancton , Zooplancton , Fitoplancton/crecimiento & desarrollo , Fitoplancton/clasificación , Zooplancton/clasificación , China , Animales , Rotíferos/crecimiento & desarrollo , Calidad del Agua , Eutrofización , Copépodos/crecimiento & desarrollo , Cladóceros/crecimiento & desarrollo , Plancton/clasificación , Cianobacterias/crecimiento & desarrollo , Dinámica Poblacional
11.
Huan Jing Ke Xue ; 45(7): 3995-4005, 2024 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-39022947

RESUMEN

Danjiangkou Reservoir is a critical water source for the South-to-North Water Diversion Project, which harbors a diverse bacterioplankton community with varying depths, and the understanding of its nitrogen and phosphorus cycle and associated driving factors remains limited. In this study, we selected five ecological sites within Danjiangkou Reservoir and conducted metagenomics analysis to investigate the vertical distribution of bacterioplankton communities in the surface, middle, and bottom layers. Furthermore, we analyzed and predicted the function of nitrogen and phosphorus cycles, along with their driving factors. Our findings revealed the dominance of Proteobacteria, Actinobacteria, and Planctomycetes in the Danjiangkou Reservoir. Significant differences were observed in the structure of bacterioplankton communities across different depths, with temperature (T), oxidation-reduction potential (ORP), dissolved oxygen (DO), and Chla identified as primary factors influencing the bacterioplankton composition. Analysis of nitrogen cycle functional genes identified 39 genes, including gltB, glnA, gltD, gdhA, NRT, etc., which were involved in seven main pathways, encompassing nitrogen fixation, nitrification, denitrification, and dissimilatory nitrate reduction. Phosphorus cycle function gene analysis identified 54 genes, including pstS, ppx-gppA, glpQ, ppk1, etc., primarily participating in six main pathways, including organic P mineralization, inorganic P solubilization, and regulatory. Cluster analysis indicated that different depths were significant factors influencing the composition and abundance of nitrogen and phosphorus cycle functional genes. The composition and abundance of nitrogen and phosphorus cycle functional genes in the surface and bottom layers differed and were generally higher than those in the middle layer. Deinococcus, Hydrogenophaga, Limnohabitans, Clavibacter, and others were identified as key species involved in the nitrogen and phosphorus cycle. Additionally, we found significant correlations between nitrogen and phosphorus cycle functional genes and environmental factors such as DO, pH, T, total dissolved solids (TDS), electrical conductivity (EC), and Chla. Furthermore, the content of these environmental factors exhibited depth-related changes in the Danjiangkou Reservoir, resulting in a distinct vertical distribution pattern of bacterioplankton nitrogen and phosphorus cycle functional genes. Overall, this study sheds light on the composition, function, and influencing factors of bacterioplankton communities across different layers of Danjiangkou Reservoir, offering valuable insights for the ecological function and diversity protection of bacterioplankton in this crucial reservoir ecosystem.


Asunto(s)
Nitrógeno , Fósforo , Plancton , Fósforo/metabolismo , China , Nitrógeno/metabolismo , Plancton/genética , Plancton/metabolismo , Bacterias/genética , Bacterias/metabolismo , Bacterias/clasificación , Proteobacteria/genética , Ciclo del Nitrógeno , Actinobacteria/genética , Actinobacteria/metabolismo , Genes Bacterianos
12.
Microbiome ; 12(1): 126, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39010229

RESUMEN

BACKGROUND: Single amplified genomes (SAGs) and metagenome-assembled genomes (MAGs) are the predominant sources of information about the coding potential of uncultured microbial lineages, but their strengths and limitations remain poorly understood. Here, we performed a direct comparison of two previously published collections of thousands of SAGs and MAGs obtained from the same, global environment. RESULTS: We found that SAGs were less prone to chimerism and more accurately reflected the relative abundance and the pangenome content of microbial lineages inhabiting the epipelagic of the tropical and subtropical ocean, as compared to MAGs. SAGs were also better suited to link genome information with taxa discovered through 16S rRNA amplicon analyses. Meanwhile, MAGs had the advantage of more readily recovering genomes of rare lineages. CONCLUSIONS: Our analyses revealed the relative strengths and weaknesses of the two most commonly used genome recovery approaches in environmental microbiology. These considerations, as well as the need for better tools for genome quality assessment, should be taken into account when designing studies and interpreting data that involve SAGs or MAGs. Video Abstract.


Asunto(s)
Bacterias , Metagenoma , Plancton , ARN Ribosómico 16S , ARN Ribosómico 16S/genética , Bacterias/genética , Bacterias/clasificación , Plancton/genética , Plancton/clasificación , Plancton/microbiología , Filogenia , Agua de Mar/microbiología , Quimerismo , Genoma Bacteriano , Metagenómica/métodos , Microbiota/genética , Genómica
13.
Sci Data ; 11(1): 720, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956105

RESUMEN

Calcification and biomass production by planktonic marine organisms influences the global carbon cycle and fuels marine ecosystems. The major calcifying plankton group coccolithophores are highly diverse, comprising ca. 250-300 extant species. However, coccolithophore size (a key functional trait) and degree of calcification are poorly quantified, as most of our understanding of this group comes from a small number of species. We generated a novel reference dataset of coccolithophore morphological traits, including cell-specific data for coccosphere and cell size, coccolith size, number of coccoliths per cell, and cellular calcite content. This dataset includes observations from 1074 individual cells and represents 61 species from 25 genera spanning equatorial to temperate coccolithophore populations that were sampled during the Atlantic Meridional Transect (AMT) 14 cruise in 2004. This unique dataset can be used to explore relationships between morphological traits (cell size and cell calcite) and environmental conditions, investigate species-specific and community contributions to pelagic carbonate production, export and plankton biomass, and inform and validate coccolithophore representation in marine ecosystem and biogeochemical models.


Asunto(s)
Haptophyta , Océano Atlántico , Plancton , Biomasa , Calcificación Fisiológica , Carbonato de Calcio , Ecosistema
14.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39000327

RESUMEN

Microbial biofilms pose severe problems in the medical field and food industry, as they are the cause of many serious infections and food-borne diseases. The extreme biofilms' resistance to conventional anti-microbial treatments presents a major challenge to their elimination. In this study, the difference in resistance between Staphylococcus aureus DSMZ 12463 biofilms, biofilm-detached cells, and planktonic cells against microcapsules containing carvacrol was assessed. The antimicrobial/antibiofilm activity of low pH disinfection medium containing the microencapsulated carvacrol was also studied. In addition, the effect of low pH on the in vitro carvacrol release from microcapsules was investigated. The minimum inhibitory concentration of microencapsulated carvacrol was 0.625 mg mL-1. The results showed that biofilms exhibited greater resistance to microencapsulated carvacrol than the biofilm-detached cells and planktonic cells. Low pH treatment alone, by hydrochloric acid addition, showed no bactericidal effect on any of the three states of S. aureus strain. However, microencapsulated carvacrol was able to significantly reduce the planktonic cells and biofilm-detached cells below the detection limit (no bacterial counts), and the biofilm by approximatively 3 log CFU mL-1. In addition, results showed that microencapsulated carvacrol combined with low pH treatment reduced biofilm by more than 5 log CFU mL-1. Thus, the use of microencapsulated carvacrol in acidic environment could be a promising approach to combat biofilms from abiotic surfaces.


Asunto(s)
Antibacterianos , Biopelículas , Cimenos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Biopelículas/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Cimenos/farmacología , Concentración de Iones de Hidrógeno , Antibacterianos/farmacología , Plancton/efectos de los fármacos , Cápsulas , Composición de Medicamentos/métodos , Farmacorresistencia Bacteriana/efectos de los fármacos
15.
Philos Trans R Soc Lond B Biol Sci ; 379(1908): 20230178, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39005032

RESUMEN

Environmental DNA metabarcoding (eDNA metaB) is fundamental for monitoring marine biodiversity and its spread in coastal ecosystems. We applied eDNA metaB to seawater samples to investigate the spatiotemporal variability of plankton and small pelagic fish, comparing sites with different environmental conditions across a coast-to-offshore gradient at river mouths along the Campania coast (Italy) over 2 years (2020-2021). We found a marked seasonality in the planktonic community at the regional scale, likely owing to the hydrodynamic connection among sampling sites, which was derived from numerical simulations. Nonetheless, spatial variability among plankton communities was detected during summer. Overall, slight changes in plankton and fish composition resulted in the potential reorganization of the pelagic food web at the local scale. This work supports the utility of eDNA metaB in combination with hydrodynamic modelling to study marine biodiversity in the water column of coastal systems. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'.


Asunto(s)
Biodiversidad , Código de Barras del ADN Taxonómico , ADN Ambiental , Peces , Cadena Alimentaria , Plancton , Animales , Peces/genética , Peces/fisiología , Italia , ADN Ambiental/análisis , Plancton/genética , Plancton/fisiología , Agua de Mar , Análisis Espacio-Temporal , Estaciones del Año
16.
Philos Trans R Soc Lond B Biol Sci ; 379(1909): 20230169, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39034696

RESUMEN

Marine plankton communities form intricate networks of interacting organisms at the base of the food chain, and play a central role in regulating ocean biogeochemical cycles and climate. However, predicting plankton community shifts in response to climate change remains challenging. While species distribution models are valuable tools for predicting changes in species biogeography under climate change scenarios, they generally overlook the key role of biotic interactions, which can significantly shape ecological processes and ecosystem responses. Here, we introduce a novel statistical framework, association distribution modelling (ADM), designed to model and predict ecological associations distribution in space and time. Applied on a Tara Oceans genome-resolved metagenomics dataset, the present-day biogeography of ADM-inferred marine plankton associations revealed four major biogeographic biomes organized along a latitudinal gradient. We predicted the evolution of these biome-specific communities in response to a climate change scenario, highlighting differential responses to environmental change. Finally, we explored the functional potential of impacted plankton communities, focusing on carbon fixation, outlining the predicted evolution of its geographical distribution and implications for ecosystem function.This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'.


Asunto(s)
Cambio Climático , Modelos Biológicos , Plancton , Plancton/fisiología , Cadena Alimentaria , Ecosistema , Organismos Acuáticos/fisiología , Océanos y Mares
17.
J Appl Microbiol ; 135(8)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39020257

RESUMEN

AIMS: This research aimed to analyze cutting board surfaces in seafood markets to find Vibrio parahaemolyticus, assess the isolates' ability to form biofilms, generate and evaluate characteristics of plasma-activated water (PAW), and compare the effect of PAW on planktonic and biofilm cells of the isolated V. parahaemolyticus strains. METHODS AND RESULTS: A total of 11 V. parahaemolyticus strains were isolated from 8.87% of the examined cutting boards. Biofilm-forming ability was evaluated for these isolates at temperatures of 10°C, 20°C, and 30°C using crystal violet staining. Four strains with the highest biofilm potential were selected for further analysis. The pH of the PAW used in the study was 3.41 ± 0.04, and the initial concentrations of hydrogen peroxide, nitrate, and nitrite were 108 ± 9.6, 742 ± 61, and 36.3 ± 2.9 µM, respectively. However, these concentrations decreased significantly within 3-4 days during storage at room temperature. PAW exhibited significant antimicrobial effects on V. parahaemolyticus planktonic cells, reducing viable bacteria up to 4.54 log CFU/ml within 20 min. PAW also reduced the number of biofilm cells on stainless steel (up to 3.55 log CFU/cm2) and high-density polyethylene (up to 3.06 log CFU/cm2) surfaces, although to a lesser extent than planktonic cells. CONCLUSIONS: PAW exhibited significant antibacterial activity against V. parahaemolyticus cells, although its antibacterial properties diminished over time. Furthermore, the antibacterial activity of PAW against biofilm cells of V. parahaemolyticus was less pronounced compared to the planktonic cells. Therefore, the actual effectiveness of PAW in seafood processing environments can be affected by biofilms that may form on various surfaces such as cutting boards if they are not cleaned properly.


Asunto(s)
Biopelículas , Alimentos Marinos , Vibrio parahaemolyticus , Vibrio parahaemolyticus/fisiología , Vibrio parahaemolyticus/aislamiento & purificación , Biopelículas/crecimiento & desarrollo , Alimentos Marinos/microbiología , Gases em Plasma/farmacología , Microbiología de Alimentos , Plancton/fisiología , Acero Inoxidable
18.
Environ Sci Technol ; 58(32): 14249-14259, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39079691

RESUMEN

Polyphosphate (polyP) is found in plankton of diverse aquatic ecosystems and is important for plankton ecology and biogeochemical cycling. However, our knowledge of polyP in aquatic environments is hindered by a lack of data due to the limitations of quantification methods. The estimate of polyP in model organisms using phenol-chloroform extraction followed by enzymatic hydrolysis is complicated and fails for environmental samples. The commonly used 4',6-diamidino-2-phenylindole (DAPI) fluorescence method for environmental studies, on the contrary, severely overestimates polyP due to interference. In this paper, we develop a plankton lysis buffer to extract polyP and a quantification method using a novel polyP-specific fluorescence dye JC-D7. We test the methods using cultured algae and bacteria, as well as natural samples from marine and freshwater environments. We show that our plankton lysis extracts polyP with high recovery while requiring substantially less time and effort. Subsequent polyP quantification using JC-D7 fluorescence overcomes the interference encountered by the DAPI method and provides an accurate measurement of polyP down to <0.5 µmol L-1. This novel method enables more accurate quantification of polyP in aquatic environments and will profoundly enhance our knowledge of polyP, plankton ecology, and biogeochemistry.


Asunto(s)
Colorantes Fluorescentes , Plancton , Polifosfatos , Colorantes Fluorescentes/química
19.
mBio ; 15(8): e0038324, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-38980008

RESUMEN

Seasonal fluctuations profoundly affect marine microeukaryotic plankton composition and metabolism, but accurately tracking these changes has been a long-standing challenge. In this study, we present a year-long metatranscriptomic data set from the Southern Bight of the North Sea, shedding light on the seasonal dynamics in temperate plankton ecosystems. We observe distinct shifts in active plankton species and their metabolic processes in response to seasonal changes. We characterized the metabolic signatures of different seasonal phases in detail, thereby revealing the metabolic versatility of dinoflagellates, the heterotrophic dietary strategy of Phaeocystis during its late-stage blooms, and stark variations in summer and fall diatom abundance and metabolic activity across nearby sampling stations. Our data illuminate the varied contributions of microeukaryotic taxa to biomass production and nutrient cycling at different times of the year and allow delineation of their ecological niches. IMPORTANCE: Ecosystem composition and metabolic functions of temperate marine microeukaryote plankton are strongly influenced by seasonal dynamics. Although monitoring of species composition of microeukaryotes has expanded recently, few methods also contain seasonally resolved information on ecosystem functioning. We generated a year-long spatially resolved metatranscriptomic data set to assess seasonal dynamics of microeukaryote species and their associated metabolic functions in the Southern Bight of the North Sea. Our study underscores the potential of metatranscriptomics as a powerful tool for advancing our understanding of marine ecosystem functionality and resilience in response to environmental changes, emphasizing its potential in continuous marine ecosystem monitoring to enhance our ecological understanding of the ocean's eukaryotic microbiome.


Asunto(s)
Plancton , Estaciones del Año , Mar del Norte , Plancton/genética , Plancton/metabolismo , Plancton/clasificación , Ecosistema , Agua de Mar/microbiología , Dinoflagelados/genética , Dinoflagelados/metabolismo , Dinoflagelados/crecimiento & desarrollo , Diatomeas/genética , Diatomeas/metabolismo , Diatomeas/clasificación , Diatomeas/crecimiento & desarrollo , Transcriptoma , Perfilación de la Expresión Génica , Metagenómica
20.
Mar Pollut Bull ; 206: 116776, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39079477

RESUMEN

Silicon (Si) utilization is not limited to eukaryotes. Recent research has suggested that the pattern of a large contribution of picocyanobacteria to biogenic silica (bSi) stocks might be widespread in the oligotrophic open ocean. We are the first to measure the size-fractionated bSi standing stocks and production rates in the oligotrophic South China Sea (SCS), which has obvious characteristics of oligotrophic waters. The 150 m integrated bSi standing stocks in the pico-sized fractions averaged 23 % of the total; the contribution of picoplankton to the total bSi production rate was 44 %. Interestingly, our estimated contributions of Synechococcus alone to the <2 µm bSi standing stock and < 2 µm bSi production rates averaged 14 % and 66 %, respectively, indicating that the significant and persistent contribution of bSi was strongly associated with marine picocyanobacteria. Furthermore, the dynamic changes in nutrient concentrations, especially in DIN and DIP, also potentially affected the variability in picoplankton bSi stocks and production rates, while the effects of temperature and salinity were not obvious. In this study, we have provided new information on measurable bSi in the picoplankton size fraction and its production rate in the SCS. We have demonstrated that picoplankton contributes a measurable, and at times significant, proportion to both the total bSi standing stock and its production rate in the SCS. A high silicon content within picocyanobacteria has important implications for understanding both their ecology and their contribution to biogeochemistry.


Asunto(s)
Océanos y Mares , Agua de Mar , Dióxido de Silicio , China , Agua de Mar/química , Monitoreo del Ambiente , Fitoplancton , Plancton/metabolismo , Synechococcus/metabolismo , Synechococcus/crecimiento & desarrollo , Salinidad
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