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[PMID]:29408405
[Au] Autor:Wang H; Park BS; Lim WA; Ki JS
[Ad] Endereço:Department of Biotechnology, Sangmyung University, Seoul 03016, South Korea.
[Ti] Título:CpMCA, a novel metacaspase gene from the harmful dinoflagellate Cochlodinium polykrikoides and its expression during cell death.
[So] Source:Gene;651:70-78, 2018 Apr 20.
[Is] ISSN:1879-0038
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Metacaspases (MCAs) are cysteine proteases that share sequence homology with caspases, and may play roles in programmed cell death (PCD). In the present study, we identified a novel MCA gene (CpMCA) from the red tide dinoflagellate Cochlodinium polykrikoides, and examined its molecular characteristics and gene expression in response to algicide-induced cell death. CpMCA cDNA is 1164 bp in length, containing a dinoflagellate spliced leader sequence (dinoSL), an 879-bp open reading frame (ORF), which codes for a 293-aa protein, and a poly (A) tail. Multi-sequence comparison indicated that CpMCA belongs to type I MCA, but it has a different structure at the N-terminal. Phylogenetic analysis showed that C. polykrikoides may have acquired the MCA gene from bacteria by means of horizontal gene transfer (HGT). In addition, expressions of CpMCA significantly increased following exposure to the common algicides copper sulfate and oxidizing chlorine, which trigger cell death in dinoflagellates, suggesting that CpMCA may be involved in cell death.
[Mh] Termos MeSH primário: Caspases/genética
Dinoflagelados/genética
[Mh] Termos MeSH secundário: Morte Celular/efeitos dos fármacos
Morte Celular/genética
DNA Complementar
DNA de Protozoário
Dinoflagelados/efeitos dos fármacos
Dinoflagelados/enzimologia
Expressão Gênica
Transferência Genética Horizontal
Genes Bacterianos
Genes de Protozoários
Herbicidas/farmacologia
Filogenia
Análise de Sequência de DNA
Transcrição Genética/efeitos dos fármacos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Complementary); 0 (DNA, Protozoan); 0 (Herbicides); EC 3.4.22.- (Caspases)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180207
[St] Status:MEDLINE


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[PMID]:28448468
[Au] Autor:Williams E; Place A; Bachvaroff T
[Ad] Endereço:Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, 701 East Pratt St., Baltimore, MD 21202, USA. williamse@umces.edu.
[Ti] Título:Transcriptome Analysis of Core Dinoflagellates Reveals a Universal Bias towards "GC" Rich Codons.
[So] Source:Mar Drugs;15(5), 2017 Apr 27.
[Is] ISSN:1660-3397
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Although dinoflagellates are a potential source of pharmaceuticals and natural products, the mechanisms for regulating and producing these compounds are largely unknown because of extensive post-transcriptional control of gene expression. One well-documented mechanism for controlling gene expression during translation is codon bias, whereby specific codons slow or even terminate protein synthesis. Approximately 10,000 annotatable genes from fifteen "core" dinoflagellate transcriptomes along a range of overall guanine and cytosine (GC) content were used for codonW analysis to determine the relative synonymous codon usage (RSCU) and the GC content at each codon position. GC bias in the analyzed dataset and at the third codon position varied from 51% and 54% to 66% and 88%, respectively. Codons poor in GC were observed to be universally absent, but bias was most pronounced for codons ending in uracil followed by adenine (UA). GC bias at the third codon position was able to explain low abundance codons as well as the low effective number of codons. Thus, we propose that a bias towards codons rich in GC bases is a universal feature of core dinoflagellates, possibly relating to their unique chromosome structure, and not likely a major mechanism for controlling gene expression.
[Mh] Termos MeSH primário: Composição de Bases/genética
Códon/genética
Dinoflagelados/genética
Sequência Rica em GC/genética
Transcriptoma/genética
[Mh] Termos MeSH secundário: Viés
Perfilação da Expressão Gênica/métodos
Filogenia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Codon)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170428
[St] Status:MEDLINE


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[PMID]:28464391
[Au] Autor:Lawrence SA; Floge SA; Davy JE; Davy SK; Wilson WH
[Ad] Endereço:School of Biological Sciences, Victoria University of Wellington, Wellington, 6140, New Zealand.
[Ti] Título:Exploratory analysis of Symbiodinium transcriptomes reveals potential latent infection by large dsDNA viruses.
[So] Source:Environ Microbiol;19(10):3909-3919, 2017 Oct.
[Is] ISSN:1462-2920
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Coral reefs are in decline worldwide. Much of this decline is attributable to mass coral bleaching events and disease outbreaks, both of which are linked to anthropogenic climate change. Despite increased research effort, much remains unknown about these phenomena, especially the causative agents of many coral diseases. In particular, coral-associated viruses have received little attention, and their potential roles in coral diseases are largely unknown. Previous microscopy studies have produced evidence of viral infections in Symbiodinium, the endosymbiotic algae critical for coral survival, and more recently molecular evidence of Symbiodinium-infecting viruses has emerged from metagenomic studies of corals. Here, we took an exploratory whole-transcriptome approach to virus gene discovery in three different Symbiodinium cultures. An array of virus-like genes was found in each of the transcriptomes, with the majority apparently belonging to the nucleocytoplasmic large DNA viruses. Upregulation of virus-like gene expression following stress experiments indicated that Symbiodinium cells may host latent or persistent viral infections that are induced via stress. This was supported by analysis of host gene expression, which showed changes consistent with viral infection after exposure to stress. If these results can be replicated in Symbiodinium cells in hospite, they could help to explain the breakdown of the coral-Symbiodinium symbiosis, and possibly some of the numerous coral diseases that have yet to be assigned a causative agent.
[Mh] Termos MeSH primário: Vírus de DNA/genética
Dinoflagelados/genética
Dinoflagelados/virologia
Transcriptoma/genética
[Mh] Termos MeSH secundário: Animais
Antozoários/fisiologia
Mudança Climática
Recifes de Corais
Simbiose/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180221
[Lr] Data última revisão:
180221
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE
[do] DOI:10.1111/1462-2920.13782


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[PMID]:29364606
[Au] Autor:Rumyantseva KV; Kosolapova NG; Kosolapov DB
[Ti] Título:[Relations between Bacterioplankton, Heterotrophic Nanoflagellates, and Virioplankton in the Littoral Zone of a LarRe Plain Reservoir:. ImDact of Bird Colonies.]
[So] Source:Mikrobiologiia;85(5):588-597, 2016 Sep.
[Is] ISSN:0026-3656
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Interactions of the main components of microbial planktonic food web (bacteria, heterotrophic nanoflagellates, and viruses) were studied in a protected overgrown littoral zone of the Rybinsk Reservoir (Upper Volga).. The effect of bird colonial, settlements (the Laridae family) on these processes was deter- mined. The following systems exhibited significant negative correlations: "heterotrophic nanoflagellates- large rod-shaped bacteria" ("predator-prey"), "viruses-bacteriophages-bacterial products" ("parasite-. host") and "heterotrophic nanoflagellates-viruses-bacteriophages." Relations between biotic factors con- trolling bacterial development were more pronounced outside the zone affected by colonial bird settlements. Near the bird colony the role of viruses in mortality of planktonic bacteria increased. Reproduction of bacte- rial cells accelerated in response to the increase in feeding activity of heterotrophic nanoflagellates. Viruses- bacteriophages and heterotrophic nanoflagellates probably eliminate different targets until medium-sized cells become predominant in the bacterial community. Then heterotrophic nanoflagellates consume bacterial cells infected with viruses.
[Mh] Termos MeSH primário: Bactérias/crescimento & desenvolvimento
Charadriiformes/fisiologia
Dinoflagelados/crescimento & desenvolvimento
Processos Heterotróficos/fisiologia
Plâncton/crescimento & desenvolvimento
Vírus/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Animais
Bactérias/virologia
Carga Bacteriana
Contagem de Células
Dinoflagelados/microbiologia
Dinoflagelados/virologia
Ecossistema
Cadeia Alimentar
Plâncton/microbiologia
Plâncton/virologia
Tanques/microbiologia
Tanques/virologia
Federação Russa
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180208
[Lr] Data última revisão:
180208
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180125
[St] Status:MEDLINE


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[PMID]:29337581
[Au] Autor:Guberman-Pfeffer MJ; Greco JA; Birge RR; Frank HA; Gascón JA
[Ad] Endereço:Department of Chemistry, University of Connecticut , Storrs, Connecticut 06269-3060, United States.
[Ti] Título:Light Harvesting by Equally Contributing Mechanisms in a Photosynthetic Antenna Protein.
[So] Source:J Phys Chem Lett;9(3):563-568, 2018 Feb 01.
[Is] ISSN:1948-7185
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We report supramolecular quantum mechanics/molecular mechanics simulations on the peridinin-chlorophyll a protein (PCP) complex from the causative algal species of red tides. These calculations reproduce for the first time quantitatively the distinct peridinin absorptions, identify multichromophoric molecular excitations, and elucidate the mechanisms regulating the strongly allowed S (1 A ) → S (1 B ) absorptions of the bound peridinins that span a 58 nm spectral range in the region of maximal solar irradiance. We discovered that protein binding site-imposed conformations, local electrostatics, and electronic coupling contribute equally to the spectral inhomogeneity. Electronic coupling causes coherent excitations among the densely packed pigments. Complementary pairing of tuning mechanisms is the result of a competition between pigment-pigment and pigment-environment interactions. We found that the aqueous solvent works in concert with the charge distribution of PCP to produce a strong correlation between peridinin spectral bathochromism and the local dielectric environment.
[Mh] Termos MeSH primário: Proteínas de Ligação à Clorofila/química
Clorofila/química
Fotossíntese
[Mh] Termos MeSH secundário: Carotenoides
Dinoflagelados
Proliferação Nociva de Algas
Luz
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorophyll Binding Proteins); 1406-65-1 (Chlorophyll); 33281-81-1 (peridinin); 36-88-4 (Carotenoids); YF5Q9EJC8Y (chlorophyll a)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180207
[Lr] Data última revisão:
180207
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jpclett.7b03211


  6 / 3274 MEDLINE  
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[PMID]:29186143
[Au] Autor:Klueter A; Trapani J; Archer FI; McIlroy SE; Coffroth MA
[Ad] Endereço:Department of Geology, State University of New York at Buffalo, Buffalo, New York, United States of America.
[Ti] Título:Comparative growth rates of cultured marine dinoflagellates in the genus Symbiodinium and the effects of temperature and light.
[So] Source:PLoS One;12(11):e0187707, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Many dinoflagellate microalgae of the genus Symbiodinium form successful symbioses with a large group of metazoans and selected protists. Yet knowledge of growth kinetics of these endosymbionts and their ecological and evolutionary implications is limited. We used a Bayesian biphasic generalized logistic model to estimate key parameters of the growth of five strains of cultured Symbiodinium, S. microadriaticum (cp-type A194; strain 04-503), S. microadriaticum (cp-type A194; strain CassKB8), S. minutum (cp-type B184; strain Mf 1.05b.01.SCI.01), S. psygmophilum (cp-type B224; strain Mf 11.05b.01) and S. trenchii (cp-type D206; strain Mf 2.2b), grown in four different combinations of temperature and light. Growth kinetics varied among Symbiodinium strains and across treatments. Biphasic growth was especially evident for S. minutum and S. psygmophilum across all treatments. Monophasic growth was more common when final asymptotic densities were relatively low (~ 200 million cells ml-1). All species tended to grow faster and / or reached a higher asymptote at 26°C than at 18°C. The fastest growth was exhibited by S. minutum, with an approximate four-fold increase in estimated cell density after 60 days. The strongest effect of light was seen in S. trenchii, in which increasing light levels resulted in a decrease in initial growth rate, and an increase in asymptotic density, time when growth rate was at its maximum, final growth rate, and maximum growth rate. Results suggest that Symbiodinium species have different photokinetic and thermal optima, which may affect their growth-related nutritional physiology and allow them to modify their response to environmental changes.
[Mh] Termos MeSH primário: Dinoflagelados/crescimento & desenvolvimento
Luz
Biologia Marinha
Temperatura Ambiente
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171226
[Lr] Data última revisão:
171226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171130
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0187707


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[PMID]:29182651
[Au] Autor:Natsuike M; Saito R; Fujiwara A; Matsuno K; Yamaguchi A; Shiga N; Hirawake T; Kikuchi T; Nishino S; Imai I
[Ad] Endereço:Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Hokkaido, Japan.
[Ti] Título:Evidence of increased toxic Alexandrium tamarense dinoflagellate blooms in the eastern Bering Sea in the summers of 2004 and 2005.
[So] Source:PLoS One;12(11):e0188565, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The eastern Bering Sea has a vast continental shelf, which contains various endangered marine mammals and large fishery resources. Recently, high numbers of toxic A. tamarense resting cysts were found in the bottom sediment surface of the eastern Bering Sea shelf, suggesting that the blooms have recently occurred. However, little is known about the presence of A. tamarense vegetative cells in the eastern Bering Sea. This study's goals were to detect the occurrence of A. tamarense vegetative cells on the eastern Bering Sea shelf and to find a relationship between environmental factors and their presence. Inter-annual field surveys were conducted to detect A. tamarense cells and environmental factors, such as nutrients, salinity, chlorophyll a, and water temperature, along a transect line on the eastern Bering Sea shelf during the summers of 2004, 2005, 2006, 2009, 2012, and 2013. A. tamarense vegetative cells were detected during every sampling year, and their quantities varied greatly from year to year. The maximum cell densities of A. tamarense observed during the summers of 2004 and 2005 were much higher than the Paralytic shellfish poisoning warning levels, which are greater than 100-1,000 cells L-1, in other subarctic areas. Lower quantities of the species occurred during the summers of 2009, 2012, and 2013. A significant positive correlation between A. tamarense quantity and water temperature and significant negative correlations between A. tamarense quantity and nutrient concentrations (of phosphate, silicate, and nitrite and nitrate) were detected in every sampling period. The surface- and bottom-water temperatures varied significantly from year to year, suggesting that water temperatures, which have been known to affect the cell growth and cyst germination of A. tamarense, might have affected the cells' quantities in the eastern Bering Sea each summer. Thus, an increase in the Bering Sea shelf's water temperature during the summer will increase the frequency and scale of toxic blooms and the toxin contamination of plankton feeders. This poses serious threats to humans and the marine ecosystem.
[Mh] Termos MeSH primário: Dinoflagelados/metabolismo
Eutrofização
Água do Mar/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171226
[Lr] Data última revisão:
171226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171129
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0188565


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[PMID]:29045489
[Au] Autor:Litaker RW; Holland WC; Hardison DR; Pisapia F; Hess P; Kibler SR; Tester PA
[Ad] Endereço:National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Fisheries and Habitat Research, Beaufort, North Carolina, United States of America.
[Ti] Título:Ciguatoxicity of Gambierdiscus and Fukuyoa species from the Caribbean and Gulf of Mexico.
[So] Source:PLoS One;12(10):e0185776, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Dinoflagellate species belonging to the genera Gambierdiscus and Fukuyoa produce ciguatoxins (CTXs), potent neurotoxins that concentrate in fish causing ciguatera fish poisoning (CFP) in humans. While the structures and toxicities of ciguatoxins isolated from fish in the Pacific and Caribbean are known, there are few data on the variation in toxicity between and among species of Gambierdiscus and Fukuyoa. Quantifying the differences in species-specific toxicity is especially important to developing an effective cell-based risk assessment strategy for CFP. This study analyzed the ciguatoxicity of 33 strains representing seven Gambierdiscus and one Fukuyoa species using a cell based Neuro-2a cytotoxicity assay. All strains were isolated from either the Caribbean or Gulf of Mexico. The average toxicity of each species was inversely proportional to growth rate, suggesting an evolutionary trade-off between an investment in growth versus the production of defensive compounds. While there is 2- to 27-fold variation in toxicity within species, there was a 1740-fold difference between the least and most toxic species. Consequently, production of CTX or CTX-like compounds is more dependent on the species present than on the random occurrence of high or low toxicity strains. Seven of the eight species tested (G. belizeanus, G. caribaeus, G. carolinianus, G. carpenteri, Gambierdiscus ribotype 2, G. silvae and F. ruetzleri) exhibited low toxicities, ranging from 0 to 24.5 fg CTX3C equivalents cell-1, relative to G. excentricus, which had a toxicity of 469 fg CTX3C eq. cell-1. Isolates of G. excentricus from other regions have shown similarly high toxicities. If the hypothesis that G. excentricus is the primary source of ciguatoxins in the Atlantic is confirmed, it should be possible to identify areas where CFP risk is greatest by monitoring only G. excentricus abundance using species-specific molecular assays.
[Mh] Termos MeSH primário: Ciguatoxinas/toxicidade
Dinoflagelados/química
[Mh] Termos MeSH secundário: Análise de Variância
Animais
Região do Caribe
Linhagem Celular
Golfo do México
Camundongos
Especificidade da Espécie
Testes de Toxicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
11050-21-8 (Ciguatoxins)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171019
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185776


  9 / 3274 MEDLINE  
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[PMID]:28763480
[Au] Autor:Drumm K; Liebst-Olsen M; Daugbjerg N; Moestrup Ø; Hansen PJ
[Ad] Endereço:Marine Biological Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
[Ti] Título:Effects of irradiance and prey deprivation on growth, cell carbon and photosynthetic activity of the freshwater kleptoplastidic dinoflagellate Nusuttodinium (= Gymnodinium) aeruginosum (Dinophyceae).
[So] Source:PLoS One;12(8):e0181751, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The freshwater dinoflagellate Nusuttodinium aeruginosum lacks permanent chloroplasts. Rather it sequesters chloroplasts as well as other cell organelles, like mitochondria and nuclei, from ingested cryptophyte prey. In the present study, growth rates, cell production and photosynthesis were measured at seven irradiances, ranging from 10 to 140 µmol photons m-2s-1, when fed the cryptophyte Chroomonas sp. Growth rates were positively influenced by irradiance and increased from 0.025 d-1 at 10 µmol photons m-2s-1 to maximum growth rates of ~0.3 d-1 at irradiances ≥ 40 µmol photons m-2s-1. Similarly, photosynthesis ranged from 1.84 to 36.9 pg C cell-1 h-1 at 10 and 140 µmol photons m-2s-1, respectively. The highest rates of photosynthesis in N. aeruginosum only corresponded to ~25% of its own cell carbon content and estimated biomass production. The measured rates of photosynthesis could not explain the observed growth rates at high irradiances. Cultures of N. aeruginosum subjected to prey starvation were able to survive for at least 27 days in the light. The sequestered chloroplasts maintained their photosynthetic activity during the entire period of starvation, during which the population underwent 4 cell divisions. This indicates that N. aeruginosum has some control of the chloroplasts, which may be able to replicate. In conclusion, N. aeruginosum seems to be in an early stage of chloroplast acquisition with some control of its ingested chloroplasts.
[Mh] Termos MeSH primário: Carbono/metabolismo
Núcleo Celular/metabolismo
Cloroplastos/metabolismo
Dinoflagelados/fisiologia
Mitocôndrias/metabolismo
Fotossíntese
[Mh] Termos MeSH secundário: Biomassa
Criptófitas
Relação Dose-Resposta à Radiação
Água Doce
Luz
Microscopia de Fluorescência
Fótons
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
7440-44-0 (Carbon)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170802
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0181751


  10 / 3274 MEDLINE  
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[PMID]:28750320
[Au] Autor:Taira H; Taguchi S
[Ad] Endereço:Laboratory of Biological Oceanography, Soka University, 1-236 Tangi-Cho, Hachioji, Tokyo 192-8857, Japan.
[Ti] Título:Cellular Mycosporine-like amino acids protect photosystem II of the Dinoflagellate Scrippsiella sweeneyae from ultraviolet radiation damage.
[So] Source:J Photochem Photobiol B;174:27-34, 2017 Sep.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Photo-damage to photosystem II (PSII) from ultraviolet radiation (UVR) was determined using chlorophyll fluorescence in relation to sunscreen factors on the dinoflagellate Scrippsiella sweeneyae based on the cellular mycosporine-like amino acid contents (C ) and cell diameter (=light path, d). Three different C were prepared by acclimating cells to three levels (30.8, 15.2, and 7.7Wm ) of photosynthetically active radiation (PAR). PAR-acclimated cells were exposed to PAR (0.64Wm )+UVR (3.94W m =2.51Wm UVB+1.43Wm UVA) for 12min. High PAR (HL) and medium PAR (NDF1) treatments acclimated cells to induce shinorine and porphyra-334 (longer λ at 333 and 334nm); whereas, the low PAR (NDF2) treatment acclimated cells to induce mycosporine-glycine and palythine (shorter λ at 310 and 320nm). Absorption spectra for the individual MAAs were reconstructed using the λ and C and were summed to reconstruct the absorption of the total C (m cell ) to estimate the sunscreen factor (S ) at λ . The highest S was obtained for cells that acclimated to the highest PAR (highest C and longest d); whereas, the lowest S was obtained for cells acclimated to the lowest PAR (the lowest C and the shortest d). C contributed approximately 94%, whereas d contributed <6%, of the sunscreen factor (S ). UVR-induced damage was indexed with a temporal decrease in the optimum quantum yield (F /F ) in the Photosystem II. The highest damage was observed for cells acclimated to the lowest S (lowest C and shortest d); whereas, the lowest damage was observed for cells acclimated to the highest S (highest C and longest d). The C mitigated most of the UVR-induced damage in photosystem II of the dinoflagellate S. sweeneyae.
[Mh] Termos MeSH primário: Aminoácidos/metabolismo
Dinoflagelados/metabolismo
Dinoflagelados/efeitos da radiação
Complexo de Proteína do Fotossistema II/metabolismo
Raios Ultravioleta/efeitos adversos
[Mh] Termos MeSH secundário: Clorofila/metabolismo
Dinoflagelados/citologia
Fotossíntese/efeitos da radiação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids); 0 (Photosystem II Protein Complex); 1406-65-1 (Chlorophyll); YF5Q9EJC8Y (chlorophyll a)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171012
[Lr] Data última revisão:
171012
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE



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