scholarly journals Diel Rhythms of Marine Picoplanktonic Communities Assessed by Comparative Metaproteomics

2020 ◽  
Author(s):  
Augustin Geron ◽  
Johannes Werner ◽  
Philippe Lebaron ◽  
Ruddy Wattiez ◽  
Sabine Matallana-Surget
Keyword(s):  
Temporal Structure ◽  
Diel Cycle ◽  
Taxonomic Structure ◽  
Specific Response ◽  
Free Living ◽  
Form Complex ◽  
North West ◽  
Attached Bacteria ◽  
First Time ◽  
Dependent Processes

Abstract Background Diel cycle is of enormous biological importance in that it imposes temporal structure on ecosystem productivity. In the world oceans, microorganisms form complex communities that carry out about half of photosynthesis and the bulk of life-sustaining nutrient cycling. Within these natural microbial assemblages, photoautotrophs, such as Cyanobacteria , display diel rhythmicity in gene expression. To what extent autotrophs and heterotrophs are impacted by light and dark oscillations and how this collectively influences community structure and functionality remains poorly documented. In this study, we compared eight day/night metaproteome profiles of Cyanobacteria and both free-living and attached bacterial fractions from picoplanktonic communities sampled over two consecutive days from the surface north-west Mediterranean Sea. Results Our results showed similar taxonomic structure in both free-living and particle-attached bacteria, dominated by Alphaproteobacteria and Gammaproteobacteria . Temporal rhythmicity in protein expression was observed in both Synechococcales and Rhodobacterales in light-dependent processes such as photosynthesis or UV-stress response. Other biological processes, such as phosphorus or amino acid metabolisms, were also found to cycle in phototrophs. In contrast, proteins from the ubiquitous Pelagibacterales remained stable independently of the day/night oscillations. Conclusion This work integrated for the first time diel comparative metaproteomics on both free-living and particle attached bacterial fractions in coastal oligotrophic environment. Our findings demonstrated a taxa-specific response to diel cycle with a more controlled protein regulation for phototrophs. This study provided additional evidences that timekeeping mechanisms might be widespread among bacteria, broadening our knowledge on diel microbial assemblage dynamics.

scholarly journals Diel Protein Regulation of Marine Picoplanktonic Communities Assessed by Metaproteomics

2021 ◽  
Vol 9 (12) ◽  
pp. 2621
Author(s):  
Augustin Géron ◽  
Johannes Werner ◽  
Philippe Lebaron ◽  
Ruddy Wattiez ◽  
Sabine Matallana-Surget
Keyword(s):  
Heterotrophic Bacteria ◽  
Temporal Structure ◽  
Sea Surface ◽  
Diel Cycle ◽  
Diel Variation ◽  
Protein Regulation ◽  
Free Living ◽  
Bacterial Populations ◽  
Form Complex ◽  
Attached Bacteria

The diel cycle is of enormous biological importance in that it imposes temporal structure on ecosystem productivity. In the world’s oceans, microorganisms form complex communities that carry out about half of photosynthesis and the bulk of life-sustaining nutrient cycling. How the functioning of microbial communities is impacted by day and night periods in surface seawater remains to be elucidated. In this study, we compared the day and night metaproteomes of the free-living and the particle-attached bacterial fractions from picoplanktonic communities sampled from the northwest Mediterranean Sea surface. Our results showed similar taxonomic distribution of free-living and particle-attached bacterial populations, with Alphaproteobacteria, Gammaproteobacteria and Cyanobacteria being the most active members. Comparison of the day and night metaproteomes revealed that free-living and particle-attached bacteria were more active during the day and the night, respectively. Interestingly, protein diel variations were observed in the photoautotroph Synechococcales and in (photo)-heterotrophic bacteria such as Flavobacteriales, Pelagibacterales and Rhodobacterales. Moreover, our data demonstrated that diel cycle impacts light-dependent processes such as photosynthesis and UV-stress response in Synechococcales and Rhodobacterales, respectively, while the protein regulation from the ubiquitous Pelagibacterales remained stable over time. This study unravels, for the first time, the diel variation in the protein expression of major free-living and particle-attached microbial players at the sea surface, totaling an analysis of eight metaproteomes.

Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

2018 ◽  
Author(s):  
Elaine A. Kelly ◽  
Judith E. Houston ◽  
Rachel Evans
Keyword(s):  
Real Time ◽  
Absorption Spectroscopy ◽  
Self Assembly ◽  
Uv Light ◽  
Wormlike Micelles ◽  
Tetraethylene Glycol ◽  
Light Illumination ◽  
First Time ◽  
Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such as<i></i>drug delivery and micellar catalysis. Currently, their behaviour in the equilibrium <i>cis-</i>and <i>trans</i>-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>) using small-angle neutron scattering (SANS). We show that the incorporation of <i>in-situ</i>UV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>could switch between wormlike micelles (<i>trans</i>native state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked <i>in</i><i>-situ</i>through combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

scholarly journals First Report of Echinococcus ortleppi in Free-Living Wild Boar (Sus scrofa) from Portugal

2021 ◽  
Vol 9 (6) ◽  
pp. 1256
Author(s):  
Teresa Letra Mateus ◽  
Maria João Gargaté ◽  
Anabela Vilares ◽  
Idalina Ferreira ◽  
Manuela Rodrigues ◽  
...  
Keyword(s):  
Wild Boar ◽  
Internal Transcribed Spacer ◽  
Sus Scrofa ◽  
One Health ◽  
Control Strategies ◽  
Free Living ◽  
First Report ◽  
Wildlife Reservoirs ◽  
First Time ◽  
Echinococcus Granulosus Sensu Lato

Cystic echinococcosis (CE) is a zoonosis that is prevalent worldwide. It is considered endemic in Portugal but few studies have been performed on Echinococcus granulosus sensu lato and their hosts. In this study, CE cysts are reported for the first time in a free-living wild boar (Sus scrofa) in Portugal. The presence of the metacestodes in the liver of the wild boar was identified by morphological features, microscopic examination and molecular analysis. The sequencing of part of the DNA nuclear ribosomal internal transcribed spacer-1 (ITS-1) region revealed a G5 genotype that presently corresponds to Echinococcus ortleppi. This is the first report of E. ortleppi in Portugal and to the best of the authors’ knowledge, in Europe. These results suggest that wild boar may be a host of CE, namely, crossing the livestock–wildlife interface, which has important public health implications. Wildlife reservoirs must be taken into account as CE hosts and surveillance of game as well as health education for hunters should be implemented using a One Health approach, with implementation of feasible and tailor-made control strategies, namely, proper elimination of byproducts in the field.

scholarly journals A circadian clock in a nonphotosynthetic prokaryote

2021 ◽  
Vol 7 (2) ◽  
pp. eabe2086
Author(s):  
Zheng Eelderink-Chen ◽  
Jasper Bosman ◽  
Francesca Sartor ◽  
Antony N. Dodd ◽  
Ákos T. Kovács ◽  
...  
Keyword(s):  
Temperature Compensation ◽  
Temporal Structure ◽  
Bacterial Biofilm ◽  
Circadian Clocks ◽  
Industrial Processes ◽  
Free Living ◽  
Considerable Potential ◽  
Free Running ◽  
Free Running Period ◽  
Constant Dark

Circadian clocks create a 24-hour temporal structure, which allows organisms to occupy a niche formed by time rather than space. They are pervasive throughout nature, yet they remain unexpectedly unexplored and uncharacterized in nonphotosynthetic bacteria. Here, we identify in Bacillus subtilis circadian rhythms sharing the canonical properties of circadian clocks: free-running period, entrainment, and temperature compensation. We show that gene expression in B. subtilis can be synchronized in 24-hour light or temperature cycles and exhibit phase-specific characteristics of entrainment. Upon release to constant dark and temperature conditions, bacterial biofilm populations have temperature-compensated free-running oscillations with a period close to 24 hours. Our work opens the field of circadian clocks in the free-living, nonphotosynthetic prokaryotes, bringing considerable potential for impact upon biomedicine, ecology, and industrial processes.

Arthropods in the nests of lesser spotted eagle (Aquila pomarina)

Biologia ◽  
2009 ◽  
Vol 64 (5) ◽  
Author(s):  
Ján Krištofík ◽  
Peter Mašán ◽  
Zbyšek Šustek ◽  
Dušan Karaska
Keyword(s):  
Trophic Group ◽  
Trophic Groups ◽  
Significant Component ◽  
Free Living ◽  
Parasitic Species ◽  
Number Of Species ◽  
Aquila Pomarina ◽  
Investigation Period ◽  
First Time

AbstractIn 2001–2007, altogether 57 nests of lesser spotted eagle were collected in the Orava region in northwestern Slovakia and four groups of arthropods were extracted from them. Richest in number of species and individuals were mites (23 species, 17,500 ind.), followed by beetles (12 species, 725 ind.), whereas pseudoscorpions were represented only by Pselaphochernes scorpioides (39 ind.) and fleas by Ceratophyllus garei (3 ind.). Unlike nests of other birds, free-living mites predominated in the nests fauna (83% of individuals), followed by nidicolous species with more or less free relationship to the nests, while parasitic species represented only a negligible part of the fauna. For the first time we observed phoresy of Nenteria pandioni, a specific and abundant mite in the eagles’ nests, on the nidicolous staphylinid Haploglossa puncticollis. The beetle fauna in the nests was much poorer than in nests of other birds. The predatory H. puncticollis was dominant in the nests (83%) and occurred continuously during the whole investigation period. Other beetles, even the widely distributed nidicols such as the histerid Gnathoncus buyssoni, were found rarely in nests. Predators were also the only abundant trophic group of beetles in the nests, while other trophic groups of beetles abundantly co-occur in nests of majority of other birds. The occurrence of all beetles was very unevenly distributed during the investigation period, but was positively correlated with occurrence of mites. The relatively low number of species and individuals of mites and beetles in the lesser spotted eagle nests resulted from their position on tree tops, at a height of 20–30 m and their quick drying out by sun and wind. It was also indicated by an enormously low number of species and individuals of mycetophagous beetles, which represent a significant component of the fauna in nests of other birds.

Ten New Records of Free-living Nematodes from Uttarakhand, India

2018 ◽  
Vol 41 (1) ◽  
pp. 39-42
Author(s):  
Vinita Sharma ◽  
Keyword(s):  
Medicinal Plants ◽  
New Records ◽  
Nematode Species ◽  
Forest Trees ◽  
Wildlife Sanctuary ◽  
Free Living ◽  
First Time

Ten nematode species of order Dorylaimida were recorded for the first time from Uttarakhand during survey of terrestrial nematodes associated with forest trees and medicinal plants in Govind Wildlife Sanctuary, Uttarkashi, Uttarakhand, India.

A new and two known species of Hatschekia Poche, 1902 (Copepoda, Siphonostomatoida, Hatschekiidae) parasitic on Japanese fishes

Crustaceana ◽  
2018 ◽  
Vol 91 (12) ◽  
pp. 1483-1493
Author(s):  
Kunihiko Izawa
Keyword(s):  
Free Living ◽  
First Time ◽  
Branchiostegus Japonicus

Abstract Hatschekia laeopsi sp. nov., H. branchiostegi Yamaguti, 1939 and H. pagrosomi Yamaguti, 1939 are (re-)described based on specimens collected from the branchial lamellae of three Japanese fishes, Laeops kitaharae (Smith & Pope, 1906) (Pleuronectidae), Branchiostegus japonicus (Houttuyn, 1782) (Malacanthidae), and Dentex tumifrons (Temminck & Schlegel, 1843) (Sparidae), respectively. The free-living stages of H. branchiostegi are described for the species for the first time.

scholarly journals Diversity of Free-Living and Attached Bacteria in Offshore Western Mediterranean Waters as Depicted by Analysis of Genes Encoding 16S rRNA

1999 ◽  
Vol 65 (2) ◽  
pp. 514-522 ◽  
Author(s):  
Silvia G. Acinas ◽  
Josefa Antón ◽  
Francisco Rodríguez-Valera
Keyword(s):  
16S Rdna ◽  
Restriction Analysis ◽  
Western Mediterranean ◽  
Bacterial Cells ◽  
Free Living ◽  
Attached Bacteria ◽  
Genes Encoding ◽  
Community Fingerprinting ◽  
Close Relatives ◽  
Alteromonas Macleodii

ABSTRACT In a previous study (S. G. Acinas, F. Rodrı́guez-Valera, and C. Pedrós-Alió, FEMS Microbiol. Ecol. 24:27–40, 1997), community fingerprinting by 16S rDNA restriction analysis applied to Mediterranean offshore waters showed that the free-living pelagic bacterial community was very different from the bacterial cells aggregated or attached to particles of more than about 8 μm. Here we have studied both assemblages at three depths (5, 50, and 400 m) by cloning and sequencing the 16S rDNA obtained from the same samples, and we have also studied the samples by scanning electron microscopy to detect morphology patterns. As expected, the sequences retrieved from the assemblages were very different. The subsample of attached bacteria contained very little diversity, with close relatives of a well-known species of marine bacteria, Alteromonas macleodii, representing the vast majority of the clones at every depth. On the other hand, the free-living assemblage was highly diverse and varied with depth. At 400 m, close relatives of cultivated γProteobacteria predominated, but as shown by other authors, near the surface most clones were related to phylotypes described only by sequence, in which the α Proteobacteria of the SAR11 cluster predominated. The new technique of rDNA internal spacer analysis has been utilized, confirming these results. Clones representative of the A. macleodii cluster have been completely sequenced, producing a picture that fits well with the idea that they could represent a genus with at least two species and with a characteristic depth distribution.

scholarly journals Notes on protected and threatened plants in Castilla y León (North-West Spain)

2020 ◽  
Vol 41 (2) ◽  
pp. 213-220
Author(s):  
Fermín Del Egido ◽  
Patricio Bariego ◽  
Alberto Rodríguez ◽  
María Santos Vicente
Keyword(s):  
Plant Species ◽  
New Records ◽  
Vascular Plant ◽  
Geographic Range ◽  
Threatened Plants ◽  
North West ◽  
Castilla Y Leon ◽  
Vascular Plant Species ◽  
New Findings ◽  
First Time

We provide new records and notes on 25 protected and/or threatened vascular plant species in Castilla y León. Some of them illustrate not only new findings but also an interesting expansion of their geographic range. Eight taxa are reported for the first time in some provinces, while eleven of them were two or three times previously reported.

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