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1
Badger, Murray R., T. John Andrews, S. M. Whitney, Martha Ludwig, David C. Yellowlees, W. Leggat, and G. Dean Price. "The diversity and coevolution of Rubisco, plastids, pyrenoids, and chloroplast-based CO2-concentrating mechanisms in algae." Canadian Journal of Botany 76, no. 6 (June 1, 1998): 1052–71. http://dx.doi.org/10.1139/b98-074.
Testo completoAbstract (sommario):
Algae have adopted two primary strategies to maximize the performance of Rubisco in photosynthetic CO2 fixation. This has included either the development of a CO2-concentrating mechanism (CCM), based at the level of the chloroplast, or the evolution of the kinetic properties of Rubisco. This review examines the potential diversity of both Rubisco and chloroplast-based CCMs across algal divisions, including both green and nongreen algae, and seeks to highlight recent advances in our understanding of the area and future areas for research. Overall, the available data show that Rubisco enzymes from algae have evolved a higher affinity for CO2 when the algae have adopted a strategy for CO2 fixation that does not utilise a CCM. This appears to be true of both Green and Red Form I Rubisco enzymes found in green and nongreen algae, respectively. However, the Red Form I Rubisco enzymes present in nongreen algae appear to have reduced oxygenase potential at air level of O2. This has resulted in a photosynthetic physiology with a reduced potential to be inhibited by O2 and a reduced need to deal with photorespiration. In the limited number of microalgae that have been examined, there is a strong correlation between the existence of a high-affinity CCM physiology and the presence of pyrenoids in all algae, highlighting the potential importance of these chloroplast Rubisco-containing bodies. However, in macroalgae, there is greater diversity in the apparent relationships between pyrenoids and chloroplast features and the CCM physiology that the species shows. There are many examples of microalgae and macroalgae with variations in the presence and absence of pyrenoids as well as single and multiple chloroplasts per cell. This occurs in both green and nongreen algae and should provide ample material for extending studies in this area. Future research into the function of the pyrenoid and other chloroplast features, such as thylakoids, in the operation of a chloroplast-based CCM needs to be addressed in a diverse range of algal species. This should be approached together with assessment of the coevolution of Rubisco, particularly the evolution of Red Form I Rubisco enzymes, which appear to achieve superior kinetic characteristics when compared with the Rubisco of C3 higher plants, which are derived from green algal ancestors.Key words: Rubisco, CO2-concentrating mechanism, carbonic anhydrase, aquatic photosynthesis, algae, pyrenoids, inorganic carbon.
2
Cui, Jian Sheng, Xiao Hui Xu, and Yu Xin Cheng. "Study on the Characteristics of Microcystis aeruginosa Chlorophyll Fluorescence Responding on the Toxicity of HgCl2." Advanced Materials Research 726-731 (August 2013): 1538–43. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.1538.
Testo completoAbstract (sommario):
Chlorophyll fluorescence is a quick, precise, non-invasive technique which has been widely used in studies of photosynthesis in micro algae, particularly for investigations of stress physiology of micro algae. The toxicity of heavy metal Hg2+on algaM. aeruginosawas studied by the change in fluorescence intensity ofM. aeruginosaat 435 nm/680 nm which treaded with different Hg2+concentrations for 25 min. The results showed that high concentrations of Hg2+inhibited the photosynthesis ofM. aeruginosa, while a low concentration (0.0005 mg/L) of Hg2+promoted photosynthesis. When Hg2+level range from 0.001 mg/L to 0.500 mg/L, it had significant inhibition effects on photosynthesis ofM. aeruginosa. The chlorophyll fluorescence intensity increased with the concentration of Hg2+(0.001~0.400 mg/L), even the concentration of Hg2+and algal photosynthetic signal had a significant positive correlation, r=0.983 3.
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Muñoz, Jorge, Juan M. Cancino, and MarÍa X. Molina. "Effect of Encrusting Bryozoans on the Physiology of Their Algal Substratum." Journal of the Marine Biological Association of the United Kingdom 71, no. 4 (November 1991): 877–82. http://dx.doi.org/10.1017/s0025315400053522.
Testo completoAbstract (sommario):
Traditionally, colonies of encrusting epiphytic bryozoans have been regarded as biotic factors reducing photosynthetic performance in benthic algae. In this study we determined under laboratory conditions the effects of Membranipora tuberculata on the photosynthetic efficiency of the rhodophyte Gelidium rex.Encrusting bryozoans reduce to 44% the incident light reaching the algal thallus. However, concentrations of chlorophyll a and other accessory pigments are significantly higher in encrusted than in non-encrusted thalli. Consequently, photosynthetic efficiency is almost identical in both types of thalli. Although non-encrusted thalli showed a higher photosynthetic V due to higher levels of light reaching the algae, encrusted thalli exhibited a compensatory effect at low photon flux density and reached a similar P value. The detrimental effect of M. tuberculata on photosynthesis could be partially compensated by CO released from bryozoan cells, as G. rex preferred CO over HCO3 as a source of photosynthetic inorganic carbon. These results suggest that physiological interaction between bryozoans and algae, involving the interchange of metabolic substances, are likely to be important.
4
Maruyama, Shumpei, Julia R. Unsworth, Valeri Sawiccy, and Virginia M. Weis. "Algae from Aiptasia egesta are robust representations of Symbiodiniaceae in the free-living state." PeerJ 10 (July 29, 2022): e13796. http://dx.doi.org/10.7717/peerj.13796.
Testo completoAbstract (sommario):
Many cnidarians rely on their dinoflagellate partners from the family Symbiodiniaceae for their ecological success. Symbiotic species of Symbiodiniaceae have two distinct life stages: inside the host, in hospite, and outside the host, ex hospite. Several aspects of cnidarian-algal symbiosis can be understood by comparing these two life stages. Most commonly, algae in culture are used in comparative studies to represent the ex hospite life stage, however, nutrition becomes a confounding variable for this comparison because algal culture media is nutrient rich, while algae in hospite are sampled from hosts maintained in oligotrophic seawater. In contrast to cultured algae, expelled algae may be a more robust representation of the ex hospite state, as the host and expelled algae are in the same seawater environment, removing differences in culture media as a confounding variable. Here, we studied the physiology of algae released from the sea anemone Exaiptasia diaphana (commonly called Aiptasia), a model system for the study of coral-algal symbiosis. In Aiptasia, algae are released in distinct pellets, referred to as egesta, and we explored its potential as an experimental system to represent Symbiodiniaceae in the ex hospite state. Observation under confocal and differential interference contrast microscopy revealed that egesta contained discharged nematocysts, host tissue, and were populated by a diversity of microbes, including protists and cyanobacteria. Further experiments revealed that egesta were released at night. In addition, algae in egesta had a higher mitotic index than algae in hospite, were photosynthetically viable for at least 48 hrs after expulsion, and could competently establish symbiosis with aposymbiotic Aiptasia. We then studied the gene expression of nutrient-related genes and studied their expression using qPCR. From the genes tested, we found that algae from egesta closely mirrored gene expression profiles of algae in hospite and were dissimilar to those of cultured algae, suggesting that algae from egesta are in a nutritional environment that is similar to their in hospite counterparts. Altogether, evidence is provided that algae from Aiptasia egesta are a robust representation of Symbiodiniaceae in the ex hospite state and their use in experiments can improve our understanding of cnidarian-algal symbiosis.
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Smith, Val H. "Light and Nutrient Effects on the Relative Biomass of Blue-Green Algae in Lake Phytoplankton." Canadian Journal of Fisheries and Aquatic Sciences 43, no. 1 (January 1, 1986): 148–53. http://dx.doi.org/10.1139/f86-016.
Testo completoAbstract (sommario):
The factors determining the relative biomass of blue-green algae during the growing season were studied using data from 22 lakes worldwide. Multiple linear regression analyses suggest that total nitrogen (TN), total phosphorus (TP), and light (as estimated from Secchi disc transparency and the depth of the mixed layer) interact to determine the relative biomass of planktonic blue-green algae. At a fixed TN: TP ratio, blue-green relative biomass increases as light availability decreases. At a fixed light level, blue-green relative biomass also increases as the TN: TP ratio decreases. Both effects are consistent with current knowledge of algal physiology, and with a recently proposed theoretical framework for algal community structure.
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Yang, Hui, Baptiste Genot, Solange Duhamel, Ryan Kerney, and John A. Burns. "Organismal and cellular interactions in vertebrate–alga symbioses." Biochemical Society Transactions 50, no. 1 (February 28, 2022): 609–20. http://dx.doi.org/10.1042/bst20210153.
Testo completoAbstract (sommario):
Photosymbioses, intimate interactions between photosynthetic algal symbionts and heterotrophic hosts, are well known in invertebrate and protist systems. Vertebrate animals are an exception where photosynthetic microorganisms are not often considered part of the normal vertebrate microbiome, with a few exceptions in amphibian eggs. Here, we review the breadth of vertebrate diversity and explore where algae have taken hold in vertebrate fur, on vertebrate surfaces, in vertebrate tissues, and within vertebrate cells. We find that algae have myriad partnerships with vertebrate animals, from fishes to mammals, and that those symbioses range from apparent mutualisms to commensalisms to parasitisms. The exception in vertebrates, compared with other groups of eukaryotes, is that intracellular mutualisms and commensalisms with algae or other microbes are notably rare. We currently have no clear cell-in-cell (endosymbiotic) examples of a trophic mutualism in any vertebrate, while there is a broad diversity of such interactions in invertebrate animals and protists. This functional divergence in vertebrate symbioses may be related to vertebrate physiology or a byproduct of our adaptive immune system. Overall, we see that diverse algae are part of the vertebrate microbiome, broadly, with numerous symbiotic interactions occurring across all vertebrate and many algal clades. These interactions are being studied for their ecological, organismal, and cellular implications. This synthesis of vertebrate–algal associations may prove useful for the development of novel therapeutics: pairing algae with medical devices, tissue cultures, and artificial ecto- and endosymbioses.
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Buschmann, Henrik. "Into another dimension: how streptophyte algae gained morphological complexity." Journal of Experimental Botany 71, no. 11 (April 9, 2020): 3279–86. http://dx.doi.org/10.1093/jxb/eraa181.
Testo completoAbstract (sommario):
Abstract Land plants with elaborated three-dimensional (3D) body plans have evolved from streptophyte algae. The streptophyte algae are known to exhibit varying degrees of morphological complexity, ranging from single-celled flagellates to branched macrophytic forms exhibiting tissue-like organization. In this review, I discuss mechanisms by which, during evolution, filamentous algae may have gained 2D and eventually 3D body plans. There are, in principle, two mechanisms by which an additional dimension may be added to an existing algal filament or cell layer: first, by tip growth-mediated branching. An example of this mechanism is the emergence and polar expansion of root hairs from land plants. The second possibility is the rotation of the cell division plane. In this case, the plane of the forthcoming cell division is rotated within the parental cell wall. This type of mechanism corresponds to the formative cell division seen in meristems of land plants. This literature review shows that of the extant streptophyte algae, the Charophyceae and Coleochaetophyceae are capable of performing both mechanisms, while the Zygnematophyceae (the actual sister to land plants) show tip growth-based branching only. I finally discuss how apical cells with two or three cutting faces, as found in mosses, may have evolved from algal ancestors.
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Broady, Paul A. "Algae and extreme environments. Ecology and physiology." Phycologia 42, no. 3 (May 2003): 317–18. http://dx.doi.org/10.2216/i0031-8884-42-3-317.1.
Testo completo
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Barott, Katie L., Alexander A. Venn, Sidney O. Perez, Sylvie Tambutté, and Martin Tresguerres. "Coral host cells acidify symbiotic algal microenvironment to promote photosynthesis." Proceedings of the National Academy of Sciences 112, no. 2 (December 29, 2014): 607–12. http://dx.doi.org/10.1073/pnas.1413483112.
Testo completoAbstract (sommario):
Symbiotic dinoflagellate algae residing inside coral tissues supply the host with the majority of their energy requirements through the translocation of photosynthetically fixed carbon. The algae, in turn, rely on the host for the supply of inorganic carbon. Carbon must be concentrated as CO2 in order for photosynthesis to proceed, and here we show that the coral host plays an active role in this process. The host-derived symbiosome membrane surrounding the algae abundantly expresses vacuolar H+-ATPase (VHA), which acidifies the symbiosome space down to pH ∼4. Inhibition of VHA results in a significant decrease in average H+ activity in the symbiosome of up to 75% and a significant reduction in O2 production rate, a measure of photosynthetic activity. These results suggest that host VHA is part of a previously unidentified carbon concentrating mechanism for algal photosynthesis and provide mechanistic evidence that coral host cells can actively modulate the physiology of their symbionts.
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Anissimova, O. V., and M. A. Gololobova. "VI ALL-RUSSIAN SCIENTIFIC CONFERENCE WITH INTERNATIONAL PARTICIPATION “ALGAE: ISSUES ON TAXONOMY, ECOLOGY AND MONITORING APPROACHES”." Ботанический журнал 108, no. 3 (March 1, 2023): 308–10. http://dx.doi.org/10.31857/s0006813623030031.
Testo completoAbstract (sommario):
The 6th All-Russian Scientific Conference with international participation “Algae: issues on taxonomy, ecology and monitoring approaches” and the School for young scientists was held in the Zvenigorod Biological Station of M.V. Lomonosov Moscow State University, September 12–17, 2022. The conference was organized by the M.V. Lomonosov Moscow State University and the Institute of Plant Physiology named after K.A. Timiryazev RAS. 82 algologists from 30 scientific institutions of Russia, Belarus and Kazakhstan attended the conference. The main topics of the Conference: Taxon problems in algology: from morphology to molecular genetics, modern synthesis; Floristics and geography of algae: problems and modern approaches; Soil algocenoses; Structural and functional organization of planktonic and benthic algocenoses; Physiology and biochemistry of algae: theory and practical application; Algae in assessing the state and quality of the environment: modern approaches, results and prospects; Cultivation – algae as an object of biotechnology: theory and its implementation in practice; Paleoalgology and biostratigraphy. During the conference, 72 reports were presented, including 6 plenary and 16 posters.
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Al-Ghelani, H. M., A. Y. A. AlKindi, S. Amer, and Y. K. Al-Akhzami. "Harmful Algal Blooms: Physiology, Behavior, Population Dynamics and Global Impacts- A Review." Sultan Qaboos University Journal for Science [SQUJS] 10 (June 1, 2005): 1. http://dx.doi.org/10.24200/squjs.vol10iss0pp1-30.
Testo completoAbstract (sommario):
Harmful, toxic algae are now considered as one of the important players in the newly emerging environmental risk factors. The apparent global increase in harmful algal blooms (HABs) is becoming a serious problem in both aquaculture and fisheries populations. Not only has the magnitude and intensity of public health and economic impacts of these blooms increased in recent years, but the number of geographic locations experiencing toxic algal blooms has also increased dramatically. There are two primary factors causing HABs outbreaks. The natural processes such as upwelling and relaxation, and the anthropogenic loading resulting in eutrophication. However, the influence of global climate changes on algal bloom phenomenon cannot be ignored. The problem warrants development of effective strategies for the management and mitigation of HABs. Progress made in the routine coastal monitoring programs, development of methods for detection of algal species and toxins and coastal modeling activities for predicting HABs reflect the international concerns regarding the impacts of HABs. Innovative techniques using molecular probes will hopefully result in development of rapid, reliable screening methods for phycotoxins and the causative organisms.
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Al-Adilah, Hanan, Martin C. Feiters, Lucy J. Carpenter, Puja Kumari, Carl J. Carrano, Dhia Al-Bader, and Frithjof C. Küpper. "Halogens in Seaweeds: Biological and Environmental Significance." Phycology 2, no. 1 (February 18, 2022): 132–71. http://dx.doi.org/10.3390/phycology2010009.
Testo completoAbstract (sommario):
Many marine algae are strong accumulators of halogens. Commercial iodine production started by burning seaweeds in the 19th century. The high iodine content of certain seaweeds has potential pharmaceutical and nutritional applications. While the metabolism of iodine in brown algae is linked to oxidative metabolism, with iodide serving the function of an inorganic antioxidant protecting the cell and thallus surface against reactive oxygen species with implications for atmospheric and marine chemistry, rather little is known about the regulation and homoeostasis of other halogens in seaweeds in general and the ecological and biological role of marine algal halogenated metabolites (except for organohalogen secondary metabolites). The present review covers these areas, including the significance of seaweed-derived halogens and of halogens in general in the context of human diet and physiology. Furthermore, the understanding of interactions between halogenated compound production by algae and the environment, including anthropogenic impacts, effects on the ozone layer and global climate change, is reviewed together with the production of halogenated natural products by seaweeds and the potential of seaweeds as bioindicators for halogen radionuclides.
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Cota, Glenn F., and Ralph E. H. Smith. "Ecology of bottom ice algae: III. Comparative physiology." Journal of Marine Systems 2, no. 3-4 (August 1991): 297–315. http://dx.doi.org/10.1016/0924-7963(91)90038-v.
Testo completo
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Hagedorn, M., V. L. Carter, J. C. Leong, and F. W. Kleinhans. "Physiology and cryosensitivity of coral endosymbiotic algae (Symbiodinium)." Cryobiology 60, no. 2 (April 2010): 147–58. http://dx.doi.org/10.1016/j.cryobiol.2009.10.005.
Testo completo
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Pozdnyakov, Ilya, Olga Matantseva, and Sergei Skarlato. "Consensus channelome of dinoflagellates revealed by transcriptomic analysis sheds light on their physiology." Algae 36, no. 4 (December 15, 2021): 315–26. http://dx.doi.org/10.4490/algae.2021.36.12.2.
Testo completoAbstract (sommario):
Ion channels are membrane protein complexes mediating passive ion flux across the cell membranes. Every organism has a certain set of ion channels that define its physiology. Dinoflagellates are ecologically important microorganisms characterized by effective physiological adaptability, which backs up their massive proliferations that often result in harmful blooms (red tides). In this study, we used a bioinformatics approach to identify homologs of known ion channels that belong to 36 ion channel families. We demonstrated that the versatility of the dinoflagellate physiology is underpinned by a high diversity of ion channels including homologs of animal and plant proteins, as well as channels unique to protists. The analysis of 27 transcriptomes allowed reconstructing a consensus ion channel repertoire (channelome) of dinoflagellates including the members of 31 ion channel families: inwardly-rectifying potassium channels, two-pore domain potassium channels, voltage-gated potassium channels (Kv), tandem Kv, cyclic nucleotide-binding domain-containing channels (CNBD), tandem CNBD, eukaryotic ionotropic glutamate receptors, large-conductance calcium-activated potassium channels, intermediate/small-conductance calcium-activated potassium channels, eukaryotic single-domain voltage-gated cation channels, transient receptor potential channels, two-pore domain calcium channels, four-domain voltage-gated cation channels, cation and anion Cys-loop receptors, small-conductivity mechanosensitive channels, large-conductivity mechanosensitive channels, voltage-gated proton channels, inositole-1,4,5- trisphosphate receptors, slow anion channels, aluminum-activated malate transporters and quick anion channels, mitochondrial calcium uniporters, voltage-dependent anion channels, vesicular chloride channels, ionotropic purinergic receptors, animal volage-insensitive cation channels, channelrhodopsins, bestrophins, voltage-gated chloride channels H+/Cl- exchangers, plant calcium-permeable mechanosensitive channels, and trimeric intracellular cation channels. Overall, dinoflagellates represent cells able to respond to physical and chemical stimuli utilizing a wide range of Gprotein coupled receptors- and Ca2+-dependent signaling pathways. The applied approach not only shed light on the ion channel set in dinoflagellates, but also provided the information on possible molecular mechanisms underlying vital cellular processes dependent on the ion transport.
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Morelli, Luca, Paulo Cartaxana, and Sónia Cruz. "Food shaped photosynthesis: Photophysiology of the sea slug Elysia viridis fed with two alternative chloroplast donors." Open Research Europe 3 (June 28, 2023): 107. http://dx.doi.org/10.12688/openreseurope.16162.1.
Testo completoAbstract (sommario):
Background: Some Sacoglossa sea slugs integrate intracellular chloroplasts derived from the algae they feed on, a process termed kleptoplasty. The stolen chloroplasts – kleptoplasts – can maintain their functionality up to several months and support animal metabolism. However, chloroplast longevity can vary depending on sea slug species and algal donor. In this study, we focus our attention on Elysia viridis, a polyphagous species that is mostly found associated to the macroalga Codium tomentosum, but that was reported to eat other macroalgae, including Chaetomorpha sp. Methods: We have investigated the changes in E. viridis physiology when provided with the two different food sources to evaluate to which extent the photosynthetic and photoprotective mechanisms of the algae chloroplasts matched those of the plastids once in the animal cells. To perform the study, we rely on the evaluation of chlorophyll a variable fluorescence to study the photophysiologic state of the integrated kleptoplasts and the high-performance liquid chromatography (HPLC) to study variations in the photosynthetic pigments. Results: We observed that the photosynthetic efficiency of E. viridis specimens is similar to the one of the respective algal donor but specimens fed with Chaetomorpha tend to have lower performances. Significant differences appear in the non-photochemical quenching (NPQ) abilities. While sea slugs fed with C. tomentosum react to high-light stress as the algae, E. viridis hosting Chaetomorpha chloroplasts are unable to properly recover from photoinhibition or perform a functional xanthophyll cycle (XC). Conclusions: Our results showed that, even if the sea slugs fed with the two algae show photosynthetic activities like the respective algal donors, not all the photoprotective mechanisms present in Chaetomorpha can be maintained in E. viridis. This indicates that the functionality of the kleptoplasts does not depend solely on their origin but also on the degree of compatibility with the animal species integrating them.
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Fürst-Jansen, Janine M. R., Sophie de Vries, and Jan de Vries. "Evo-physio: on stress responses and the earliest land plants." Journal of Experimental Botany 71, no. 11 (January 10, 2020): 3254–69. http://dx.doi.org/10.1093/jxb/eraa007.
Testo completoAbstract (sommario):
Abstract Embryophytes (land plants) can be found in almost any habitat on the Earth’s surface. All of this ecologically diverse embryophytic flora arose from algae through a singular evolutionary event. Traits that were, by their nature, indispensable for the singular conquest of land by plants were those that are key for overcoming terrestrial stressors. Not surprisingly, the biology of land plant cells is shaped by a core signaling network that connects environmental cues, such as stressors, to the appropriate responses—which, thus, modulate growth and physiology. When did this network emerge? Was it already present when plant terrestrialization was in its infancy? A comparative approach between land plants and their algal relatives, the streptophyte algae, allows us to tackle such questions and resolve parts of the biology of the earliest land plants. Exploring the biology of the earliest land plants might shed light on exactly how they overcame the challenges of terrestrialization. Here, we outline the approaches and rationale underlying comparative analyses towards inferring the genetic toolkit for the stress response that aided the earliest land plants in their conquest of land.
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Courtecuisse, Emilie, Elias Marchetti, Kevin Oxborough, Peter D. Hunter, Evangelos Spyrakos, Gavin H. Tilstone, and Stefan G. H. Simis. "Optimising Multispectral Active Fluorescence to Distinguish the Photosynthetic Variability of Cyanobacteria and Algae." Sensors 23, no. 1 (January 1, 2023): 461. http://dx.doi.org/10.3390/s23010461.
Testo completoAbstract (sommario):
This study assesses the ability of a new active fluorometer, the LabSTAF, to diagnostically assess the physiology of freshwater cyanobacteria in a reservoir exhibiting annual blooms. Specifically, we analyse the correlation of relative cyanobacteria abundance with photosynthetic parameters derived from fluorescence light curves (FLCs) obtained using several combinations of excitation wavebands, photosystem II (PSII) excitation spectra and the emission ratio of 730 over 685 nm (Fo(730/685)) using excitation protocols with varying degrees of sensitivity to cyanobacteria and algae. FLCs using blue excitation (B) and green–orange–red (GOR) excitation wavebands capture physiology parameters of algae and cyanobacteria, respectively. The green–orange (GO) protocol, expected to have the best diagnostic properties for cyanobacteria, did not guarantee PSII saturation. PSII excitation spectra showed distinct response from cyanobacteria and algae, depending on spectral optimisation of the light dose. Fo(730/685), obtained using a combination of GOR excitation wavebands, Fo(GOR, 730/685), showed a significant correlation with the relative abundance of cyanobacteria (linear regression, p-value < 0.01, adjusted R2 = 0.42). We recommend using, in parallel, Fo(GOR, 730/685), PSII excitation spectra (appropriately optimised for cyanobacteria versus algae), and physiological parameters derived from the FLCs obtained with GOR and B protocols to assess the physiology of cyanobacteria and to ultimately predict their growth. Higher intensity LEDs (G and O) should be considered to reach PSII saturation to further increase diagnostic sensitivity to the cyanobacteria component of the community.
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NOVAKOVSKAYA, IRINA V., IRINA N. EGOROVA, NINA V. KULAKOVA, ELENA N. PATOVA, DMITRY M. SHADRIN, and OLGA V. ANISSIMOVA. "Morphological and phylogenetic relations of members of the genus Coelastrella (Scenedesmaceae, Chlorophyta) from the Ural and Khentii Mountains (Russia, Mongolia)." Phytotaxa 527, no. 1 (November 26, 2021): 1–20. http://dx.doi.org/10.11646/phytotaxa.527.1.1.
Testo completoAbstract (sommario):
We describe the morphological features and the phylogenetic relationships of five morphologically similar strains belonging to the genus Coelastrella, which live in different ecological and geographical conditions of terrestrial ecosystems: in the Ural Mountains (Polar, Subpolar, and Northern Urals of Russia) and the Khentii Mountains (Russia and Mongolia). We analysed algal strains stored in the Culture Collection of Algae of the Institute of Biology, Syktyvkar, Russia (SYKOA Ch-045-09, SYKOA Ch-047-11, SYKOA Ch-072-17) and the Culture Collection of Algae at Herbarium of the Siberian Institute of Plant Physiology and Biochemistry, Irkutsk, Russia (IRK-A 2, IRK-A 173). By light microscopy, all samples were assigned to Coelastrella terrestris. However, the phylogenetic analyses based on the nucleotide sequences of 18S rDNA and ITS1-ITS2 showed that only one strain belongs to C. terrestris (IRK-A 173). Other samples were closer to C. oocystiformis (SYKOA Ch-045-09; IRK-A 2) and C. aeroterrestrica (SYKOA Ch-047-11). The strain SYKOA Ch-072-17 is probably a new species for the genus. These results confirmed the high phenotypic variability and the hidden diversity among the members of this green algal group.
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Kateriya, Suneel, Georg Nagel, Ernst Bamberg, and Peter Hegemann. "“Vision” in Single-Celled Algae." Physiology 19, no. 3 (June 2004): 133–37. http://dx.doi.org/10.1152/nips.01517.2004.
Testo completoAbstract (sommario):
Photosynthetic unicellular algae have a unique visual system. In Chlamydomonas reinhardtii, the pigmented eye comprises the optical system and at least five different rhodopsin photoreceptors. Two of them, the channelrhodopsins, are rhodopsin-ion channel hybrids switched between closed and open states by photoisomerization of the attached retinal chromophore. They promise to become a useful tool for noninvasive control of membrane potential and intracellular ion concentrations.
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Blaby-Haas, Crysten E., and Sabeeha S. Merchant. "Comparative and Functional Algal Genomics." Annual Review of Plant Biology 70, no. 1 (April 29, 2019): 605–38. http://dx.doi.org/10.1146/annurev-arplant-050718-095841.
Testo completoAbstract (sommario):
Over 100 whole-genome sequences from algae are published or soon to be published. The rapidly increasing availability of these fundamental resources is changing how we understand one of the most diverse, complex, and understudied groups of photosynthetic eukaryotes. Genome sequences provide a window into the functional potential of individual algae, with phylogenomics and functional genomics as tools for contextualizing and transferring knowledge from reference organisms into less well-characterized systems. Remarkably, over half of the proteins encoded by algal genomes are of unknown function, highlighting the volume of functional capabilities yet to be discovered. In this review, we provide an overview of publicly available algal genomes, their associated protein inventories, and their quality, with a summary of the statuses of protein function understanding and predictions.
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Krieger, Erik C., Aleluia Taise, Wendy A. Nelson, Johan Grand, Eric Le Ru, Simon K. Davy, and Christopher E. Cornwall. "Tolerance of coralline algae to ocean warming and marine heatwaves." PLOS Climate 2, no. 1 (January 4, 2023): e0000092. http://dx.doi.org/10.1371/journal.pclm.0000092.
Testo completoAbstract (sommario):
Ocean warming (OW) and marine heatwaves (MHWs) rapidly transform marine ecosystems, especially when they impact keystone or foundation species. Foundation species such as kelps, fucoids and corals are highly sensitive to heat stress, which threatens the future of temperate seaweed forests and tropical reefs. However, functioning and resilience of these systems also relies on the less conspicuous coralline algae, whose thermal tolerances have gone largely untested. Here, we examined the sensitivity of four temperate coralline algal morphotypes from three different species to four realistic present day and future OW and MHW scenarios (ambient [16°C constant]; ambient+MHW [16°C baseline + a symmetric two-week heatwave with a peak intensity of 18.7°C]; future [18.7°C constant]; future+MHW [18.7°C baseline + a symmetric two-week heatwave with a peak intensity of 21.4°C]). Photo-physiology (e.g., Fv/Fm) and calcification physiology (e.g., proxies for calcifying fluid saturation state ΩCF) were generally unaffected by the treatments, implying a high thermo-tolerance of our study species compared to other important marine foundation species. We ascribe this mainly to their photosynthetic apparatus that, unlike in other photoautotrophs, continued to function under heat stress. Experimental evidence presented here and elsewhere implies that coralline algae are likely to continue to play their crucial ecological roles in a warming ocean. Yet, such predictions are fraught with uncertainty due to the substantial gaps in our knowledge. We attempt to highlight some of these gaps and aim to present potential physiological underpinnings of their thermo-tolerance.
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Brown, Matthew B., Matthew S. Edwards, and Kwang Young Kim. "Effects of climate change on the physiology of giant kelp, Macrocystis pyrifera, and grazing by purple urchin, Strongylocentrotus purpuratus." ALGAE 29, no. 3 (September 15, 2014): 203–15. http://dx.doi.org/10.4490/algae.2014.29.3.203.
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Meri Auliadani, Natasya, and Ludmilla Fitri Untari. "Adaptasi Morfologi Spirogyra porticalis (O. F. Mueller) Cleve dalam Proses Fikoremediasi Limbah Cair Tambak Udang Vannamei BPBAP Situbondo." Jurnal Biologi Indonesia 19, no. 1 (2023): 77–91. http://dx.doi.org/10.47349/jbi/19012023/77.
Testo completoAbstract (sommario):
Plant taxonomy is the science of identifying, describing, classifying, and naming plants. The different classifications have fundamental differences in the phylogenetic, ecological, molecular, or morphological data of each taxon. The morphology of algae is influenced by environmental conditions. Algal cells can modulate their physiology and metabolism by changing their morphology, including their shape and size, in response to environmental stresses such as nutrien limitations. Liquid waste in shrimp ponds has a high content of essential compounds, one of which is nitrogen. Nitrogen content that is too high will cause algae blooms that block the entry of light into the waters. Algae blooming can be reduced by using bioremediation with autotrophic organisms such as Spirogyra porticalis. These microorganisms are easily found in aquatic ecosystems in the form of filaments. Thus, in this study, the morphology of S. porticalis as phytoremediation was carried out in the effluent of vannamei shrimp ponds at BPBAP Situbondo. This activity was carried out for three months at the Laboratory of Growth Systematics, Faculty of Biology UGM. The results showed that there were morphological differences due to differences in salinity from the remediation process. In addition, the results of this research can contribute to the field of science, especially in the fields of taxonomy, systematics and the environment, and the results of the data can be used as a reference source needed for further research.
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Lawrence, Janice E., Corina P. D. Brussaard, and Curtis A. Suttle. "Virus-Specific Responses of Heterosigma akashiwo to Infection." Applied and Environmental Microbiology 72, no. 12 (October 13, 2006): 7829–34. http://dx.doi.org/10.1128/aem.01207-06.
Testo completoAbstract (sommario):
ABSTRACT We used flow cytometry to examine the process of cell death in the bloom-forming alga Heterosigma akashiwo during infection by a double-stranded DNA virus (OIs1) and a single-stranded RNA virus (H. akashiwo RNA virus [HaRNAV]). These viruses were isolated from the same geographic area and infect the same strain of H. akashiwo. By use of the live/dead stains fluorescein diacetate and SYTOX green as indicators of cellular physiology, cells infected with OIs1 showed signs of infection earlier than HaRNAV-infected cultures (6 to 17 h versus 23 to 29 h). Intracellular esterase activity was lost prior to increased membrane permeability during infection with OIs1, while the opposite was seen with HaRNAV-infected cultures. In addition, OIs1-infected cells accumulated in the cultures while HaRNAV-infected cells rapidly disintegrated. Progeny OIs1 viruses consisted of large and small morphotypes with estimated latent periods of 11 and 17 h, respectively, and about 1,100 and 16,000 viruses produced per cell, respectively. In contrast, HaRNAV produced about 21,000 viruses per cell and had a latent period of 29 h. This study reveals that the characteristics of viral infection in algae are virus dependent and therefore are variable among viruses infecting the same species. This is an important consideration for ecosystem modeling exercises; calculations based on in situ measurements of algal physiology must be sensitive to the diverse responses of algae to viral infection.
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Zhou, Hong, and Klaus von Schwartzenberg. "Zygnematophyceae: from living algae collections to the establishment of future models." Journal of Experimental Botany 71, no. 11 (February 19, 2020): 3296–304. http://dx.doi.org/10.1093/jxb/eraa091.
Testo completoAbstract (sommario):
Abstract The class of conjugating green algae, Zygnematophyceae (Conjugatophyceae), is extremely rich in species and has attracted the interest of phycologists for a long time. It is now widely accepted that this class of charophyte algae holds a key position in the phylogenetic tree of streptophytes, where they represent the closest relatives to all land plants (embryophytes). It is increasingly evident that robust model plants that can be easily cultivated and genetically transformed are necessary to better understand the process of terrestrialization and the related molecular, cellular, and physiological adaptations. Living algae collections play an important role, not only for phylogenomic-based taxonomy but also for screening for suitable model organisms. For this review, we screened six major public algae collections for Zygnematophyceae strains and established a cumulative list comprising 738 different taxa (including species, subspecies, varieties, and forms). From the described biodiversity with 8883 registered taxa (AlgaeBase) the cultured Zygnematophyceae taxa worldwide cover only ~8.3%. We review the past research on this clade of algae and discuss it from the perspective of establishing a model organism. We present data on the life cycle of the genera Micrasterias and Spirogyra, representing the orders Desmidiales and Zygnematales, and outline the current status of genetic transformation of Zygnematophyceae algae and future research perspectives.
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Legrand, E., T. Kutti, EV Gonzalez Casal, SPS Rastrick, S. Andersen, and V. Husa. "Reduced physiological performance in a free-living coralline alga induced by salmon faeces deposition." Aquaculture Environment Interactions 13 (June 17, 2021): 225–36. http://dx.doi.org/10.3354/aei00403.
Testo completoAbstract (sommario):
Maerl beds are formed by the accumulation of free-living coralline algae and have considerable ecological significance due to the high diversity of associated fauna and flora. The rapid expansion of the Atlantic salmon Salmo salar aquaculture industry in Norway may have major impacts on surrounding maerl beds through the release of effluents, including fish faeces. This study is the first to test the effects of salmon faeces and inorganic sediment deposition on the photosynthesis, respiration, calcification and pigment content of the coralline alga Lithothamnion soriferum. In a 6 wk laboratory experiment, inorganic sediment and salmon faeces deposition significantly reduced the amount of light reaching the surface of coralline algae. No impact of inorganic sediment deposition was detected on L. soriferum physiology, while salmon faeces deposition increased respiration rate and reduced net primary production and calcification. The accumulation of salmon faeces stimulates proliferation of bacteria, with adverse consequences on L. soriferum physiology due to the potential release of toxic compounds. Burial by salmon faeces deposition also affects the physiology of coralline algae due to the flocculation of sticky faeces particles, which may limit nutrient and gas exchanges in the vicinity of thalli. Carbon dioxide accumulation in the vicinity of L. soriferum may lead to a decline in pH and alter the calcification process in cell walls. In natural maerl beds, the negative effect of faeces deposition may be exacerbated by longer-term exposure and the presence of other chemicals released by fish farms.
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Zhao, Min, Han Xiao, Dong Sun, and Shunshan Duan. "Investigation of the Inhibitory Effects of Mangrove Leaves and Analysis of Their Active Components on Phaeocystis globosa during Different Stages of Leaf Age." International Journal of Environmental Research and Public Health 15, no. 11 (November 1, 2018): 2434. http://dx.doi.org/10.3390/ijerph15112434.
Testo completoAbstract (sommario):
The presence of harmful algal blooms (HABs) can cause significant problems to the quality of the water, the marine ecosystems, and the human health, and economy worldwide. Biological remediation can inhibit harmful algal growth efficiently in an environmental-friendly manner. Therefore, the research conducted on biological remediation with regard to the inhibition of HABs is becoming a major focus in marine ecology. To date, no study has been reported with regard to the red tides occurring in mangrove wetlands. Therefore, the present study used two mangrove species, namely Bruguiera gymnorrhiza and Kandelia candel and one harmful algae species Phaeocystis globosa as experimental organisms. The present study determined the inhibitory effects and algae physiology of specific aqueous extracts from mangrove leaves on the viability of harmful algae, and analyzed the main chemical composition of the aqueous extracts by ultra-performance liquid chromatography coupled to high resolution mass spectrometry (UPLC-QTOF-MS). The results indicated that the aqueous extracts from different leaf ages of B. gymnorrhiza and K. candel leaves exhibited apparent inhibitory effects on the growth of P. globosa. The inhibitory effects of B. gymnorrhiza and K. candel leaves aqueous extracts on the growth of P. globosa were in the following order: senescent > mature > young leaves. The levels of the parameters superoxide dismutase (SOD) activity, glutathione (GSH), and malondialdehyde (MDA)content in P. globosa following treatment with B. gymnorrhiza and K. candel leaves aqueous extracts were increased as follows: senescent > mature > young leaves. Simultaneously, the intensity of the ion peaks of the specific secondary metabolites assigned 4 (No.: 4 Rt: 2.83 min), 7 (No.: 7 Rt: 3.14 min), 8 (No.: 8 Rt: 3.24 min), 9 (No.: 9 Rt: 3.82min) and 10 (No.: 10 Rt: 4.10 min) were increased. These metabolites were found in the aqueous extracts from B. gymnorrhiza leaves. The intensities of the ion peaks of the secondary metabolites 7, 8 in the aqueous extracts from the K. candel leaves were also increased. The majority of the substances that inhibited the algae found in the mangrove plants were secondary metabolites. Therefore, we considered that the norsesquiterpenes compounds 4, 8, 9, and 10 and a phenolic glycoside compound 7 were the active constituents in the aqueous extracts of the mangrove leaves responsible for the inhibition of algae growth. This evidence provided theoretical guidance for the development of biological methods to control red tides and for the further use of substances with antiproliferative activity against algae.
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Morelli, Luca, Paulo Cartaxana, and Sónia Cruz. "Food shaped photosynthesis: Photophysiology of the sea slug Elysia viridis fed with two alternative chloroplast donors." Open Research Europe 3 (March 13, 2024): 107. http://dx.doi.org/10.12688/openreseurope.16162.2.
Testo completoAbstract (sommario):
Background Some Sacoglossa sea slugs steal and integrate chloroplasts derived from the algae they feed on into their cells where they continue to function photosynthetically, a process termed kleptoplasty. The stolen chloroplasts – kleptoplasts – can maintain their functionality up to several months and support animal metabolism. However, chloroplast longevity can vary depending on sea slug species and algal donor. In this study, we focused on Elysia viridis, a polyphagous species that is mostly found associated with the macroalga Codium tomentosum, but that was reported to eat other macroalgae, including Chaetomorpha sp. Methods We have investigated the changes in E. viridis physiology when provided with the two different food sources to evaluate to which extent the photosynthetic and photoprotective mechanisms of the algae chloroplasts matched those of the plastids once in the animal cells. To perform the study, we rely on the evaluation of chlorophyll a variable fluorescence to study the photophysiological state of the integrated kleptoplasts and high-performance liquid chromatography (HPLC) to study variations in the photosynthetic pigments. Results We observed that the photosynthetic efficiency of E. viridis is lower when fed with Chaetomorpha. Also, significant differences were observed in the non-photochemical quenching (NPQ) abilities of the sea slugs. While sea slugs fed with C. tomentosum react similarly to high-light stress as the alga, E. viridis hosting Chaetomorpha chloroplasts were unable to properly recover from photoinhibition or perform a functional xanthophyll cycle (XC). Conclusions Our results showed that, even if the sea slugs fed with the two algae show photosynthetic activities like the respective algal donors, not all the photoprotective mechanisms present in Chaetomorpha can be maintained in E. viridis. This indicates that the functionality of the kleptoplasts does not depend solely on their origin but also on the degree of compatibility with the animal species integrating them.
30
CASSELTON, P. J., G. CHANDLER, N. SHAH, G. R. STEWART, and N. SUMAR. "GLUTAMINE SYNTHETASE ISOFORMS IN ALGAE." New Phytologist 102, no. 2 (February 1986): 261–70. http://dx.doi.org/10.1111/j.1469-8137.1986.tb00580.x.
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Denny, Mark, and Brian Gaylord. "The mechanics of wave-swept algae." Journal of Experimental Biology 205, no. 10 (May 15, 2002): 1355–62. http://dx.doi.org/10.1242/jeb.205.10.1355.
Testo completoAbstract (sommario):
SUMMARYWave-swept marine algae must contend with the hydrodynamic forces imposed by extreme water velocities. Nonetheless, they seldom have a shape that appears streamlined and they are constructed of weak, compliant materials. How do they survive? The answer is complex, but a coherent story is beginning to emerge. The combined effect of frond shape and material properties ensures that algae are flexible. In small individuals, flexibility allows the plant to reorient and reconfigure in flow, thereby assuming a streamlined shape and reducing the applied hydrodynamic force. In large individuals, flexibility allows fronds to `go with the flow', a strategy that can at times allow the plant to avoid hydrodynamic forces but may at other times impose inertial loads. Our understanding of algal mechanics is such that we can begin to predict the survivorship of algae as a function of size, spatial distribution and wave climate.
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Guolan, Huang, Sun Hongwen, and Cong Li Li. "Study on the physiology and degradation of dye with immobilized algae." Artificial Cells, Blood Substitutes, and Biotechnology 28, no. 4 (January 2000): 347–63. http://dx.doi.org/10.3109/10731190009119364.
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Jüttner, F. "Physiology and biochemistry of odorous compounds from freshwater cyanobacteria and algae." Water Science and Technology 31, no. 11 (June 1, 1995): 69–78. http://dx.doi.org/10.2166/wst.1995.0405.
Testo completoAbstract (sommario):
Freshwater cyanobacteria and algae are responsible for the formation of a wide spectrum of different odorous compounds that are frequently observed in natural waters and are the causes consumer complaints. The physiology and biochemistry of odorous compounds that are permanently in the cells or excreted into the environment are here described, as are the odorous compounds that are generated only after disintegration of the cells and are produced by the initiation of lipoxygenase and carotene oxygenase reactions.
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Sansone, Clementina, Christophe Brunet, Douglas M. Noonan, and Adriana Albini. "Marine Algal Antioxidants as Potential Vectors for Controlling Viral Diseases." Antioxidants 9, no. 5 (May 7, 2020): 392. http://dx.doi.org/10.3390/antiox9050392.
Testo completoAbstract (sommario):
As the COVID-19 epidemic expands in the world, and with the previous SARS epidemic, avian flu, Ebola and AIDS serving as a warning, biomedical and biotechnological research has the task to find solutions to counteract viral entry and pathogenesis. A novel approach can come from marine chemodiversity, recognized as a relevant source for developing a future natural “antiviral pharmacy”. Activities of antioxidants against viruses can be exploited to cope with human viral infection, from single individual infections to protection of populations. There is a potentially rich and fruitful reservoir of such compounds thanks to the plethora of bioactive molecules and families present in marine microorganisms. The aim of this communication is to present the state-of-play of what is known on the antiviral activities recognized in (micro)algae, highlighting the different molecules from various algae and their mechanisms of actions, when known. Given the ability of various algal molecules—mainly sulfated polysaccharides—to inhibit viral infection at Stage I (adsorption and invasion of cells), we envisage a need to further investigate the antiviral ability of algae, and their mechanisms of action. Given the advantages of microalgal production compared to other organisms, the opportunity might become reality in a short period of time.
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Cornwall, Christopher E., Steeve Comeau, Hollie Putnam, and Verena Schoepf. "Impacts of ocean warming and acidification on calcifying coral reef taxa: mechanisms responsible and adaptive capacity." Emerging Topics in Life Sciences 6, no. 1 (February 14, 2022): 1–9. http://dx.doi.org/10.1042/etls20210226.
Testo completoAbstract (sommario):
Ocean warming (OW) and acidification (OA) are two of the greatest global threats to the persistence of coral reefs. Calcifying reef taxa such as corals and coralline algae provide the essential substrate and habitat in tropical reefs but are at particular risk due to their susceptibility to both OW and OA. OW poses the greater threat to future reef growth and function, via its capacity to destabilise the productivity of both taxa, and to cause mass bleaching events and mortality of corals. Marine heatwaves are projected to increase in frequency, intensity, and duration over the coming decades, raising the question of whether coral reefs will be able to persist as functioning ecosystems and in what form. OA should not be overlooked, as its negative impacts on the calcification of reef-building corals and coralline algae will have consequences for global reef accretion. Given that OA can have negative impacts on the reproduction and early life stages of both coralline algae and corals, the interdependence of these taxa may result in negative feedbacks for reef replenishment. However, there is little evidence that OA causes coral bleaching or exacerbates the effects of OW on coral bleaching. Instead, there is some evidence that OA alters the photo-physiology of both taxa. Tropical coralline algal possess shorter generation times than corals, which could enable more rapid evolutionary responses. Future reefs will be dominated by taxa with shorter generation times and high plasticity, or those individuals inherently resistant and resilient to both marine heatwaves and OA.
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Xue, Yiming, Beining Xue, and Liusuo Zhang. "Multi-Omics Integrative Analysis to Reveal the Impacts of Shewanella algae on the Development and Lifespan of Marine Nematode Litoditis marina." International Journal of Molecular Sciences 25, no. 16 (August 22, 2024): 9111. http://dx.doi.org/10.3390/ijms25169111.
Testo completoAbstract (sommario):
Understanding how habitat bacteria affect animal development, reproduction, and aging is essential for deciphering animal biology. Our recent study showed that Shewanella algae impaired Litoditis marina development and lifespan, compared with Escherichia coli OP50 feeding; however, the underlying mechanisms remain unclear. Here, multi-omics approaches, including the transcriptome of both L. marina and bacteria, as well as the comparative bacterial metabolome, were utilized to investigate how bacterial food affects animal fitness and physiology. We found that genes related to iron ion binding and oxidoreductase activity pathways, such as agmo-1, cdo-1, haao-1, and tdo-2, were significantly upregulated in L. marina grown on S. algae, while extracellular structural components-related genes were significantly downregulated. Next, we observed that bacterial genes belonging to amino acid metabolism and ubiquinol-8 biosynthesis were repressed, while virulence genes were significantly elevated in S. algae. Furthermore, metabolomic analysis revealed that several toxic metabolites, such as puromycin, were enriched in S. algae, while many nucleotides were significantly enriched in OP50. Moreover, we found that the “two-component system” was enriched in S. algae, whereas “purine metabolism” and “one-carbon pool by folate” were significantly enriched in E. coli OP50. Collectively, our data provide new insights to decipher how diet modulates animal fitness and biology.
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Moulin, Solène L. Y., Audrey Beyly-Adriano, Stéphan Cuiné, Stéphanie Blangy, Bertrand Légeret, Magali Floriani, Adrien Burlacot, et al. "Fatty acid photodecarboxylase is an ancient photoenzyme that forms hydrocarbons in the thylakoids of algae." Plant Physiology 186, no. 3 (April 15, 2021): 1455–72. http://dx.doi.org/10.1093/plphys/kiab168.
Testo completoAbstract (sommario):
Abstract Fatty acid photodecarboxylase (FAP) is one of the few enzymes that require light for their catalytic cycle (photoenzymes). FAP was first identified in the microalga Chlorella variabilis NC64A, and belongs to an algae-specific subgroup of the glucose–methanol–choline oxidoreductase family. While the FAP from C. variabilis and its Chlamydomonas reinhardtii homolog CrFAP have demonstrated in vitro activities, their activities and physiological functions have not been studied in vivo. Furthermore, the conservation of FAP activity beyond green microalgae remains hypothetical. Here, using a C. reinhardtii FAP knockout line (fap), we showed that CrFAP is responsible for the formation of 7-heptadecene, the only hydrocarbon of this alga. We further showed that CrFAP was predominantly membrane-associated and that &gt;90% of 7-heptadecene was recovered in the thylakoid fraction. In the fap mutant, photosynthetic activity was not affected under standard growth conditions, but was reduced after cold acclimation when light intensity varied. A phylogenetic analysis that included sequences from Tara Ocean identified almost 200 putative FAPs and indicated that FAP was acquired early after primary endosymbiosis. Within Bikonta, FAP was retained in secondary photosynthetic endosymbiosis lineages but absent from those that lost the plastid. Characterization of recombinant FAPs from various algal genera (Nannochloropsis, Ectocarpus, Galdieria, Chondrus) provided experimental evidence that FAP photochemical activity was present in red and brown algae, and was not limited to unicellular species. These results thus indicate that FAP was conserved during the evolution of most algal lineages where photosynthesis was retained, and suggest that its function is linked to photosynthetic membranes.
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Zachleder, V. "Origins of Algae and Their Plastids." Photosynthetica 36, no. 4 (January 1, 2000): 600. http://dx.doi.org/10.1023/a:1007020910942.
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Moroney, J. V., S. G. Bartlett, and G. Samuelsson. "Carbonic anhydrases in plants and algae." Plant, Cell & Environment 24, no. 2 (February 2001): 141–53. http://dx.doi.org/10.1111/j.1365-3040.2001.00669.x.
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Vosolsobě, Stanislav, Roman Skokan, and Jan Petrášek. "The evolutionary origins of auxin transport: what we know and what we need to know." Journal of Experimental Botany 71, no. 11 (April 4, 2020): 3287–95. http://dx.doi.org/10.1093/jxb/eraa169.
Testo completoAbstract (sommario):
Abstract Auxin, represented by indole-3-acetic acid (IAA), has for a long time been studied mainly with respect to the development of land plants, and recent evidence confirms that canonical nuclear auxin signaling is a land plant apomorphy. Increasing sequential and physiological data show that the presence of auxin transport machinery pre-dates the emergence of canonical signaling. In this review, we summarize the present state of knowledge regarding the origins of auxin transport in the green lineage (Viridiplantae), integrating both data from wet lab experiments and sequence evidence on the presence of PIN-FORMED (PIN), PIN-LIKES (PILS), and AUXIN RESISTANT 1/LIKE-AUX1 (AUX1/LAX) homologs. We discuss a high divergence of auxin carrier homologs among algal lineages and emphasize the urgent need for the establishment of good molecular biology models from within the streptophyte green algae. We further postulate and discuss two hypotheses for the ancestral role of auxin in the green lineage. First, auxin was present as a by-product of cell metabolism and the evolution of its transport was stimulated by the need for IAA sequestration and cell detoxification. Second, auxin was primarily a signaling compound, possibly of bacterial origin, and its activity in the pre-plant green algae was a consequence of long-term co-existence with bacteria in shared ecological consortia.
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Kumar, Ajay, Rahul Prasad Singh, Indrajeet Kumar, Priya Yadav, Sandeep Kumar Singh, Kaushalendra, Prashant Kumar Singh, et al. "Algal Metabolites Can Be an Immune Booster against COVID-19 Pandemic." Antioxidants 11, no. 3 (February 24, 2022): 452. http://dx.doi.org/10.3390/antiox11030452.
Testo completoAbstract (sommario):
The world has faced the challenges of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for the last two years, first diagnosed at the end of 2019 in Wuhan and widely distributed worldwide. As a result, the WHO has proclaimed the illness brought on by this virus to be a global pandemic. To combat COVID-19, researcher communities continuously develop and implement rapid diagnoses, safe and effective vaccinations and other alternative therapeutic procedures. However, synthetic drug-related side effects and high costs have piqued scientists’ interest in natural product-based therapies and medicines. In this regard, antiviral substances derived from natural resources and some medicines have seen a boom in popularity. For instance, algae are a rich source of compounds such as lectins and sulfated polysaccharides, which have potent antiviral and immunity-boosting properties. Moreover, Algae-derived compounds or metabolites can be used as antibodies and vaccine raw materials against COVID-19. Furthermore, some algal species can boost immunity, reduce viral activity in humans and be recommended for usage as a COVID-19 preventative measure. However, this field of study is still in its early stages of development. Therefore, this review addresses critical characteristics of algal metabolites, their antioxidant potential and therapeutic potential in COVID-19.
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Caisová, Lenka. "Draparnaldia: a chlorophyte model for comparative analyses of plant terrestrialization." Journal of Experimental Botany 71, no. 11 (February 26, 2020): 3305–13. http://dx.doi.org/10.1093/jxb/eraa102.
Testo completoAbstract (sommario):
Abstract It is generally accepted that land plants evolved from streptophyte algae. However, there are also many chlorophytes (a sister group of streptophyte algae and land plants) that moved to terrestrial habitats and even resemble mosses. This raises the question of why no land plants evolved from chlorophytes. In order to better understand what enabled streptophyte algae to conquer the land, it is necessary to study the chlorophytes as well. This review will introduce the freshwater filamentous chlorophyte alga Draparnaldia sp. (Chaetophorales, Chlorophyceae) as a model for comparative analyses between these two lineages. It will also focus on current knowledge about the evolution of morphological complexity in chlorophytes versus streptophytes and their respective morphological/behavioural adaptations to semi-terrestrial habitats, and will show why Draparnaldia is needed as a new model system.
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Van, Anh Tu, Veronika Sommer, and Karin Glaser. "The Ecophysiological Performance and Traits of Genera within the Stichococcus-like Clade (Trebouxiophyceae) under Matric and Osmotic Stress." Microorganisms 9, no. 9 (August 26, 2021): 1816. http://dx.doi.org/10.3390/microorganisms9091816.
Testo completoAbstract (sommario):
Changes in water balance are some of the most critical challenges that aeroterrestrial algae face. They have a wide variety of mechanisms to protect against osmotic stress, including, but not limited to, downregulating photosynthesis, the production of compatible solutes, spore and akinete formation, biofilms, as well as triggering structural cellular changes. In comparison, algae living in saline environments must cope with ionic stress, which has similar effects on the physiology as desiccation in addition to sodium and chloride ion toxicity. These environmental challenges define ecological niches for both specialist and generalist algae. One alga known to be aeroterrestrial and euryhaline is Stichococcus bacillaris Nägeli, possessing the ability to withstand both matric and osmotic stresses, which may contribute to wide distribution worldwide. Following taxonomic revision of Stichococcus into seven lineages, we here examined their physiological responses to osmotic and matric stress through a salt growth challenge and desiccation experiment. The results demonstrate that innate compatible solute production capacity under salt stress and desiccation tolerance are independent of one another, and that salt tolerance is more variable than desiccation tolerance in the Stichococcus-like genera. Furthermore, algae within this group likely occupy similar ecological niches, with the exception of Pseudostichococcus.
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Teoh, Ming-Li, Wan-Loy Chu, and Siew-Moi Phang. "Effect of temperature change on physiology and biochemistry of algae: a review." Malaysian Journal of Science 29, no. 2 (August 26, 2010): 82–97. http://dx.doi.org/10.22452/mjs.vol29no2.1.
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Young, Erica B., Lindsay Reed, and John A. Berges. "Growth parameters and responses of green algae across a gradient of phototrophic, mixotrophic and heterotrophic conditions." PeerJ 10 (July 21, 2022): e13776. http://dx.doi.org/10.7717/peerj.13776.
Testo completoAbstract (sommario):
Many studies have shown that algal growth is enhanced by organic carbon and algal mixotrophy is relevant for physiology and commercial cultivation. Most studies have tested only a single organic carbon concentration and report different growth parameters which hampers comparisons and improvements to algal cultivation methodology. This study compared growth of green algae Chlorella vulgaris and Chlamydomonas reinhardtii across a gradient of photoautotrophic-mixotrophic-heterotrophic culture conditions, with five acetate concentrations. Culture growth rates and biomass achieved were compared using different methods of biomass estimation. Both species grew faster and produced the most biomass when supplied with moderate acetate concentrations (1–4 g L−1), but light was required to optimize growth rates, biomass yield, cell size and cell chlorophyll content. Higher acetate concentration (10 g L−1) inhibited algal production. The choice of growth parameter and method to estimate biomass (optical density (OD), chlorophyll a fluorescence, flow cytometry, cell counts) affected apparent responses to organic carbon, but use of OD at 600, 680 or 750 nm was consistent. There were apparent trade-offs among exponential growth rate, maximum biomass, and culture time spent in exponential phase. Different cell responses over 1–10 g L−1 acetate highlight profound physiological acclimation across a gradient of mixotrophy. In both species, cell size vs cell chlorophyll relationships were more constrained in photoautotrophic and heterotrophic cultures, but under mixotrophy, and outside exponential growth phase, these relationships were more variable. This study provides insights into algal physiological responses to mixotrophy but also has practical implications for choosing parameters for monitoring commercial algal cultivation.
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Raven, J. A. "Iron acquisition and allocation in stramenopile algae." Journal of Experimental Botany 64, no. 8 (May 1, 2013): 2119–27. http://dx.doi.org/10.1093/jxb/ert121.
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CLODE, PETA L., MARTIN SAUNDERS, GARTH MAKER, MARTHA LUDWIG, and CRAIG A. ATKINS. "Uric acid deposits in symbiotic marine algae." Plant, Cell & Environment 32, no. 2 (February 2009): 170–77. http://dx.doi.org/10.1111/j.1365-3040.2008.01909.x.
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Buschmann, Henrik, and Andreas Holzinger. "Understanding the algae to land plant transition." Journal of Experimental Botany 71, no. 11 (June 11, 2020): 3241–46. http://dx.doi.org/10.1093/jxb/eraa196.
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Barrero-Gil, Javier, Blanca Garciadeblás, and Begoña Benito. "Sodium, Potassium-ATPases in Algae and Oomycetes." Journal of Bioenergetics and Biomembranes 37, no. 4 (August 2005): 269–78. http://dx.doi.org/10.1007/s10863-005-6637-x.
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Barros, Marcelo P., Ernani Pinto, Teresa CS Sigaud-Kutner, Karina HM Cardozo, and Pio Colepicolo. "Rhythmicity and oxidative/nitrosative stress in algae." Biological Rhythm Research 36, no. 1-2 (February 2005): 67–82. http://dx.doi.org/10.1080/09291010400028666.
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