Search results for "algae"
showing 10 items of 403 documents
Ingestion, digestion, and egestion in Spongilla lacustris (Porifera, Spongillidae) after pulse feeding with Chlamydomonas reinhardtii (Volvocales)
1993
The route followed by food particles in Spongilla lacustris was clarified by light and electron microscopic examination of sponges fed with Chlamydomonas reinhardtii. The algal cells are phagocytosed by prosendopinacocytes and choanocytes. After some time they are transferred to archaeocytes, amoebocytes, and lophocytes. Changes in algal structure during digestion were observed and the egestion of algal remnants was documented in life for the first time. In light micrographs, digestion of the algal cells is manifest first in shrinkage of the cells, then in disintegration to form several spherical green fragments 2–3 μm in diameter, and finally, after 12–18 h, in a reddish brown discoloratio…
The evolution of nitric oxide signalling diverges between the animal and the green lineages
2019
AbstractNitric oxide (NO) is a ubiquitous signalling molecule with widespread distribution in prokaryotes and eukaryotes where it is involved in countless physiological processes. While the mechanisms governing nitric oxide (NO) synthesis and signalling are well established in animals, the situation is less clear in the green lineage. Recent investigations have shown that NO synthase, the major enzymatic source for NO in animals, is absent in land plants but present in a limited number of algae. The first detailed analysis highlighted that these new NO synthases are functional but display specific structural features and probably original catalytic activities. Completing this picture, analy…
Microalgae community structure analysis based on 18S rDNA amplification from DNA extracted directly from soil as a potential soil bioindicator
2005
International audience; Soil algae are photosynthetically active microorganisms showing changeable community structure, depending on the soil type, the agricultural practices and the application of pesticides. To characterise algal community structure, molecular approaches complementary to classical microbiological approaches based on the isolation and the culture of soil algae are required. Our study describes a polymerase chain reaction (PCR) approach targeting algal 18S rDNA sequences of desoxyribonucleic acid (DNA) samples extracted either from unialgal eukaryotic microalgae culture, complex assemblages of microalgae populations or natural soil communities. Our first results showed that…
Plastid 23S rRNA gene sequence data for several algae strains
2022
The dataset consists of plastid 23S rRNA gene sequence data for several algae strains. For more information about the collection and analysis of the data, see the attached documentation.
Role of nitric oxide synthase (NOS) of Klebsormidium nitens: Identification and characterization of partners
2021
National audience; Nitric oxide (NO) is an important cellular signaling molecule across kingdoms. During bioticor abiotic stresses, NO burst is detected in both plants and mammals although no sequenceencoding the well described mammalian NO synthase (NOS) is highlighted in plants. Comparedto terrestrial plants, some algae present transcripts encoding the NOS-like enzyme. Amongthem, Klebsormidium nitens the model alga to study the early transition step from aquatic algaeto land plants is found. As mechanisms governing NO synthesis and signaling in green lineageremain unclear, the study of NOS from K. nitens (KnNOS) through (i) the identification ofregulator proteins, (ii) the identification …
Role of nitric oxide synthases from klebsormidium nitens: first structural characterization and partners identification
2022
Objectives: Nitric oxide (NO) is an important cellular signaling molecule regulating various physiologicalprocesses, in both animals and plants. In animals, NO synthesis is mainly catalyzed by NO synthase(NOS) enzymes. In plants, NOS-like activities sensitive to mammalian NOS inhibitors have beenmeasured, although no sequences encoding mammalian NOSs have been found in land plants.Interestingly, we identified NOS-like sequences in 20 algae species. These latter include thefilamentous charophyte green algae Klebsormidium nitens, a biological model to study the earlytransition step from aquatic algae to land plants. In order to understand the mechanisms governingNO synthesis and signaling in …
Role of nitric oxide synthases from Klebsormidium nitens: structural characterization and identification of protein partners
2022
Nitric oxide (NO) is an important cellular signalling molecule regulating various physiological processes, in both animals andplants. In animals, NO synthesis is mainly catalysed by NO synthase (NOS) enzymes. During biotic or abiotic stresses, NOSlike activities that are sensitive to mammalian NOS inhibitors have been detected in plants, although no sequences encodingthe well described mammalian NOS are highlighted in land plants. Interestingly, we identified NOS-like sequences in 20 algaespecies. Among them, NOSs are found in Klebsormidium nitens the model alga to study the early transition step from aquaticalgae to land plants.As mechanisms governing NO synthesis and signalling in green l…
Characterisation of NO synthases from the alga Klebsormidium nitens
2022
Nitric oxide (NO) is an important cellular signaling molecule regulating various physiological processes, in both animals and plants. In animals, NO synthesis is mainly catalyzed by NO synthase (NOS) enzymes. In plants, NOS-like activities sensitive to mammalian NOS inhibitors have been measured, although no sequences encoding mammalian NOS have been found in land plants. Interestingly, we identified NOS-like sequences in about twenty algae species. These latter include the filamentous Charophyta green algae Klebsormidium nitens, a biological model to study the early transition step from aquatic algae to land plants. Currently, two NOS were identified in K. nitens genome: i) KnNOS1 which po…
Biochemical profiling of temperate zone freshwater green microalgae grown in filtered and unfiltered recirculating aquaculture systems effluent and m…
2020
Viljelemällä mikroleviä kalojen kiertovesiviljelyn jätevedessä siitä voidaan poistaa ravinteita ja tuottaa niistä biomassaa. Menetelmää voidaan käyttää korvaamaan perinteistä jäteveden käsittelyä ja kehittämään vesiviljelyn kannattavuutta. Tässä työssä verrattiin kolmen eri viherlevälajin (Haematococcus pluvialis, Monoraphidium griffithii and Selenastrum sp.) kasvua, ravinteiden poistoa, sekä rasvahappo- ja aminohappoprofiileja, kun leviä kasvatettiin suodatetussa tai suodattamattomassa kiertovedessä tai levien elatusaineessa. Monoraphidium ja Selenastrum -lajien kasvunopeudet olivat pienemmät kiertovedessä (0.64 vrk-1 ja 0.50 vrk-1) kuin levien elatusaineessa (0.72 ja 0.59 vrk-1), mutta Ha…
Identification and functional characterization of S-nitrosated proteins from Klebsormidium nitens, a model alga to study plant adaptation to land
2022
The small gaseous molecule nitric oxide (NO) is well established as a major ubiquitous component of cell signalling. A key signalling mechanism mediating NO effects is S-nitrosation, a post-translational modification by which NO can impact the target protein activities, subcellular localizations, and capacities to form protein complexes. The identification of proteins targeted by NO is of major interest in order to elucidate NO functions. Interestingly, land plants lack NO synthase (NOS), which is the main enzyme for NO synthesis in metazoans, while a few algal species possess it, thus raising many interrogations. Therefore, we focused on the identification of S-nitrosated proteins during s…