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Artigos de revistas sobre o tema "Microorganismes marins"

Autor: Grafiati
Publicado: 26 de outubro de 2024

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1

Querellou, J. "Les microorganismes des milieux extrêmes : des grands fonds marins aux applications industrielles". Cahiers de Nutrition et de Diététique 39, n.º 6 (dezembro de 2004): 397–400. http://dx.doi.org/10.1016/s0007-9960(04)94479-3.

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NICOLAS, J. L., F. J. GATESOUPE, S. FROUEL, E. BACHERE e Y. GUEGUEN. "Quelles stratégies alternatives aux antibiotiques en aquaculture ?" INRAE Productions Animales 20, n.º 3 (7 de setembro de 2007): 253–58. http://dx.doi.org/10.20870/productions-animales.2007.20.3.3465.

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Malgré des réglementations contraignantes, l’usage des antibiotiques en préventif est encore répandu en aquaculture, particulièrement pendant les phases critiques (stades précoces, métamorphose, transferts d’animaux), mais aussi chez des animaux en croissance. En plus des améliorations que l’on peut encore apporter en matière de zootechnie et de prophylaxie traditionnelle, des méthodes alternatives sont maintenant disponibles ou en développement. Les préparations microbiennes commercialisées pour les élevages terrestres sont de plus en plus utilisées pour les élevages de crevettes et de poissons, mais chaque espèce ou élevage demanderait des expérimentations particulières pour déterminer les produits et les doses les plus efficaces. En effet, les réponses des animaux à l’ajout des probiotiques peuvent être variables et l’absence de données fiables freine leur application en routine. Les probiotiques d’origine terrestre contenant des Lactobacillus, des Bacillus ou d’autres bactéries de genres connexes, ou bien encore des levures, ne conviennent pas pour les mollusques bivalves comme les huîtres, les coquilles St Jacques, les palourdes. Seules quelques bactéries marines sélectionnées protègent les larves de bivalves contre les infections bactériennes. Cependant, l’utilisation pratique de ces bactéries gram (-) pose de nombreux problèmes d’autorisation légale, de production, de conservation et de distribution. L’intérêt des probiotiques réside dans leurs effets multiples, qui associent à des activités antibactériennes, des effets sur l’hôte telles que la stimulation de la réponse immunitaire ou celle de la croissance, bien que les mécanismes d’action ne soient pas clairement identifiés. Par contre ils n’ont pas la même efficacité que les antibiotiques pour stopper une infection. Les prébiotiques comme les fructo-oligosaccharides constituent une autre possibilité d’améliorer la santé des animaux, et des essais ont montré leur efficacité chez les alevins de turbot par exemple. Une troisième alternative est représentée par les peptides antimicrobiens. Ces molécules ont un large spectre d’activité antimicrobienne. Ils peuvent tuer des bactéries gram (-) et gram (+), des champignons ou des virus enveloppés. Plusieurs de ces peptides viennent d’être découverts chez les invertébrés marins (crevettes et huîtres), où ils sont un élément essentiel de la défense de ces animaux sans immunité acquise. Ils pourraient remplacer avantageusement les antibiotiques à terme. Ils devraient générer moins de résistances chez les microorganismes cibles, car ils agissent sur les membranes cellulaires et ils devraient être plus vite dégradés sans produire de résidus.
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Muehlstein, Lisa K. "The host – pathogen interaction in the wasting disease of eelgrass, Zostera marina". Canadian Journal of Botany 70, n.º 10 (1 de outubro de 1992): 2081–88. http://dx.doi.org/10.1139/b92-258.

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A marine epidemic of wasting disease decimated populations of eelgrass, Zostera marina L., in the early 1930s. Labyrinthula, a marine slime mold was the suspected pathogen, although the cause was never clearly determined. Presently, a recurrence of wasting disease of Z. marina was documented in populations along the coasts of North America and Europe. A pathogenic species of Labyrinthula, described as Labyrinthula zosterae Porter et Muehlstein, was identified as the primary microorganism causing the present wasting disease. Of all the microorganisms tested in laboratory disease tests, only L. zosterae caused disease symptoms. Direct microscopic observations revealed that Labyrinthula cells were found most frequently associated with marginal areas of disease symptoms and appeared to move rapidly through the tissue, directly penetrating cell walls. The ectoplasmic network that surrounds Labyrinthula cells appeared to have an important role in the enzymatic degradation of plant cell walls and presumably a role in the destruction of cytoplasmic contents of the plant cells. Direct contact of diseased leaves with healthy leaves was the mechanism of disease spread from plant to plant. Key words: Labyrinthula, Zostera marina, eelgrass wasting disease.
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Pirog, T. P. "PRACTICALLY VALUABLE METABOLITES OF MARINE MICROORGANISMS". Biotechnologia Acta 13, n.º 3 (junho de 2020): 5–29. http://dx.doi.org/10.15407/biotech13.03.005.

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SIMIDU, USIO. "Marine Microorganisms". Sen'i Gakkaishi 48, n.º 11 (1992): P578—P583. http://dx.doi.org/10.2115/fiber.48.11_p578.

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Rui, Zhang, Liu Yu, ZhaoZhi Hui, SunMei Rong, Tangjun Yu, Du Hui e Liao Yan. "The role of marine microorganisms in offshore pollution remediation". SDRP Journal of Earth Sciences & Environmental Studies 5, n.º 1 (2020): 25–34. http://dx.doi.org/10.25177/jeses.5.1.ra.10625.

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Jeasmin, Akter,, Sathi Zakia Sultana e Siddeq Md. Mahfuj Alam. "Isolation of Bioactive Secondary Metabolites From Marine Streptomyces Species". DIU Journal of Health and Life Sciences 1, n.º 01 & 02 (30 de janeiro de 2014): 10–17. http://dx.doi.org/10.36481/diuhls.v01i1-2.j13wh875.

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Marine Microorganisms and animals gaining attention biotechnologically for the isolation of bioactive metabolites. An antagonistic marine microorganism was collected from Sundarban, mangrove forest of Bangladesh. The microorganism was identified on the basis of its morphological characteristics as Streptomyces species. It was grown in the yeast-extract glucose broth media at 37.5°C for 7 days for production bioactive metabolites.Antibacterial activity of ethyl acetate and chloroform extracts of the culture filtrate was performed against Bacillus subtilis and Escherichia coli. Cytotoxic activity of the extracts wes also determined by brine shrimp lethality bioassay. The LC50 values were 2.2, 0.9, and 1.6 μg/ml for chloroform and ethyl acetate extract and cephalosporin, respectively. Further analysis is going on to isolation of the active constituents from the extracts. Keywords: Streptomyces spp, antimicrobial compound, marine microorganism, susceptibility testing &brine shrimp lethality bioassay.
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8

Sergushkina, Marta, Oksana Zaitseva, Andrey Khudyakov, Tatyana Polezhaeva, Olga Solomina e Inna Paturova. "New Possibilities of Using Zosteran Pectin from the Marine Plant Zostera marina (L.)". Journal of Biomedical Research & Environmental Sciences 4, n.º 1 (janeiro de 2023): 117–25. http://dx.doi.org/10.37871/jbres1655.

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Zosteran pectin isolated from the perennial marine plant Zostera marina (L.) has a complex molecular structure and a wide range of biological activity. Aim Study: This study aims to identify new properties (adhesive, cryoprotective) of zosteran pectin. Materials and Methods: The adhesive properties of zosteran were investigated by evaluating the microorganism adhesiveness index and the erythrocyte participation rate. To assess the cryoprotective properties of zosteran, the cryoscopic method and various methods for assessing the viability of leukocytes (cryoresistance, cell membrane integrity, and phagocytosis) were used. Results: Zosteran pectin in each assay consistently revealed more adhesive and cryoprotective properties compared to other substances. The results revealed that zosteran at a concentration of 0.3% increase the percentage of red blood cells with lactobacilli attached to their surface. The addition of zosteran to various cryoprotectants changed the osmolarity and freezing point of only the mixture of pectin with DMSO. Zosteran/DMSO cryosolution significantly better retained the viability of leukocytes after exposure to negative temperatures (-80°C), compared with a solution containing only DMSO. Conclusion: Our data reveal new properties of zosteran, due to which pectin changes the conditions of bacterial adhesive activity. This can be used to enhance the perception of microorganisms by intestinal cells in representatives of normal microflora or to reduce it in pathogens of infectious diseases. The obtained cryoprotective effect of the solution with zosteran can be used for further research on the preservation of biological objects (spermatozoa, platelets, etc.) at low temperatures.
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Hatmandi, Ariani, e Kaneo Kanoh. "ISOLATION AND STRUCTURE DETERMINATION OF ANTICANCER SUBSTANCES FROM MARINE MICROORGANISMS: A PRELIMINARY STUDY OF NEW BUTENOLIDE AS NEW ANTICANCER". Marine Research in Indonesia 33, n.º 2 (31 de dezembro de 2008): 189–93. http://dx.doi.org/10.14203/mri.v33i2.491.

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An investigation to find new anticancer substances from marine microorganisms was conducted at the Marine Biotechnology Institute, Kamaishi Campus, Iwate, Japan. The samples were from MBI microorganism collection. They were bacteria, actinomycetes and fungus. Mammalian cancer cells, A549, were used as screening medium. The method for screening of the targeted microorganism was micro plate method. HK294 was found as microorganism which has the most interesting phenomenon in inhibiting A549 cancer cells. HK294 was identified to be Streptomyces viridocyaneus (homology 99%) by its 16S rDNA sequence. The HK294 was cultured in Marine Broth medium and incubated at 30°C for seven days in 100 rpm orbital shaker incubator, to produce active substance. Silica Gel Column Chromatography and High Pressure Liquid Chromatography were used for separation of the active substances. NMR and Mass Spectrum were used for determination of the active substances. Butenolide, Teleocidin A1 and New Butenolide were isolated from this experiment. The New Butenolide is promising to be used for anticancer drug but it need further research.
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Quirós-Rodríguez, Jorge Alexander, Carlos Nisperuza-Pérez e Juan Yepes-Escobar. "Los microplásticos, una amenaza desconocida para los ecosistemas marinos de Colombia: perspectivas y desafíos a enfrentar". Gestión y Ambiente 24, n.º 1 (23 de setembro de 2021): 91615. http://dx.doi.org/10.15446/ga.v24n1.91615.

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Los plásticos están presentes en todos los aspectos de la vida cotidiana y su producción masiva alrededor del mundo ha traído consigo un área emergente de investigación: los microplásticos, estas partículas de tamaño diminuto están causando graves efectos en el ambiente marino, a tal punto que hay una creciente preocupación por los posibles efectos sobre la biota, el equilibrio de los ecosistemas marinos y la salud humana. La presente revisión tiene por objetivo brindar una visión más integrada de la contaminación por microplásticos y sus posibles problemáticas asociadas en los ecosistemas marinos y costeros de Colombia. Teniendo en cuenta la información disponible hasta la fecha, se evidencia un aumento progresivo en el estudio de estos contaminantes principalmente en cuanto a su distribución. Sin embargo, existe escaza información del efecto que puede tener sobre la biodiversidad de los ecosistemas marinos de Colombia, por ello se hizo necesario recurrir a bibliografía internacional, en la cual se atribuyen tres problemáticas a los microplásticos: la ingestión por parte de la biota marina, proliferación de microorganismos no deseados y la biomagnificación de sustancias tóxicas, lo cual respalda que estas partículas son una amenaza evidente para los ecosistemas marinos de Colombia. Finalmente, se proponen siete áreas de actuación para el estudio de estas partículas, y algunas estrategias que permitan minimizar su efecto, haciendo énfasis en que la educación pública es una parte crítica para crear cambios a nivel social.
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Lu, Xiaoling, Xiaoyu Liu, Cong Long, Guoxiang Wang, Yun Gao, Junhua Liu e Binghua Jiao. "A Preliminary Study of the Microbial Resources and Their Biological Activities of the East China Sea". Evidence-Based Complementary and Alternative Medicine 2011 (2011): 1–8. http://dx.doi.org/10.1155/2011/806485.

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East China Sea is one of the four sea areas in China, which possesses peculiar ecological environment and many kinds of living creatures, especially the microorganisms. We established the East China Sea microorganism library (during 2006–2010) for the first time, which stored about 30000 strains that covered most kinds of the species. In this paper, 395 pure strains of East China Sea microorganism library which belong to 33 different genera were mainly introduced.Sulfitobacter,Halomonas,Bacillus,Pseudoalteromonas, andIdiomarinawere the most dominant species. On the large-scale biological activity screening of the 395 strains, 100 strains possess different biological activities based on different screening models, of which 11.4% strains have antibacterial activities, 15.9% have cytotoxicity activities, and 6.1% have antioxidation activities. Besides, the secondary metabolites of 6 strains with strong biological activities were studied systematically; diketopiperazines and macrocyclic lactones are the active secondary metabolites. The species and the biological activity of microorganisms diversity, the abundant structure type of the secondary metabolites, and their bioactivities all indicate that East China Sea is a potent marine microorganisms-derived developing resource for drug discovery.
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OKAMI, Yoshiro. "Marine Microorganisms Producing Bioactives." Journal of the agricultural chemical society of Japan 65, n.º 9 (1991): 1321–29. http://dx.doi.org/10.1271/nogeikagaku1924.65.1321.

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Consi, Thomas R. "Micro-Safaris: The Display of Live Microorganisms in Public Aquariums". Marine Technology Society Journal 35, n.º 1 (1 de março de 2001): 36–47. http://dx.doi.org/10.4031/002533201787997999.

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Marine and freshwater microorganisms are important components of aquatic ecosystems but they are not commonly displayed, live, in public aquariums. In this paper I review the technical challenges involved in displaying and maintaining aquatic microorganisms. A proposed viewing system consisting of a mobile, immersed, endoscope is presented as a possible solution to these technical challenges. A set of simple experiments is described that evaluate the image characteristics generated by an endoscope used to observe live microorganisms. The results of these tests showed that the endoscope gives acceptable images in this application. Optical and mechanical problems encountered in the experiments are also discussed.Throughout the paper sources of new technology are identified that have potential applications in the development of the microorganism display systems.
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Rathnayake, Anuruddhika Udayangani, Racheal Abuine, Yong-Jae Kim e Hee-Guk Byun. "Anti-Alzheimer’s Materials Isolated from Marine Bio-resources: A Review". Current Alzheimer Research 16, n.º 10 (20 de novembro de 2019): 895–906. http://dx.doi.org/10.2174/1567205016666191024144044.

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The most common type of dementia found in the elderly population is Alzheimer’s disease. The disease not only impacts the patients and their families but also the society therefore, the main focus of researchers is to search new bioactive materials for treating AD. The marine environment is a rich source of functional ingredients and to date, we can find sufficient research relating to anti- Alzheimer’s compounds isolated from marine environment. Therefore, this review focuses on the anti- Alzheimer’s material from marine bio-resources and then expounds on the anti-Alzheimer’s compounds from marine seaweed, marine animal and marine microorganisms. Moreover, because of the complexity of the disease, different hypothesizes have been elaborated and active compounds have been isolated to inhibit different stages of pathophysiological mechanisms. Sulfated polysaccharides, glycoprotein, and enzymatic hydrolysates from marine seaweeds, peptides, dietary omega-3 polyunsaturated fatty acids and skeletal polysaccharide from marine animals and secondary metabolites from marine microorganism are summarized in this review under the anti-Alzheimer’s compounds from the marine.
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Moriñigo, M. A., M. A. Muñoz, R. Cornax, E. Martinez-Manzanares e J. J. Borrego. "Presence of Indicators and Salmonella in Natural Waters Affected by Outfall Wastewater Discharges". Water Science and Technology 25, n.º 9 (1 de maio de 1992): 1–8. http://dx.doi.org/10.2166/wst.1992.0200.

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The presence of the pathogenic microorganism Salmonella as well as indicator microorganisms (total and faecal coliforms, faecal streptococci, Clostridium perfringens, and coliphages) was investigated in three different aquatic environments affected by sewage discharges. The relationships between indicators and Salmonella depended mainly on the source of faecal discharges and on the survival capability of the microorganisms in aquatic environments. The microorganisms most closely related to Salmonella spp were faecal coliforms and C. perfringens, the latter yielding also the highest linear regression slope value. Detection percentages of Salmonella spp were high even at a low level of pollution, which allowed detection of the pathogens in the absence of classical indicator microorganisms in the sample. The results obtained in the present study showed that there were no differences in survival rates between the serotypes of Salmonella tested. Moreover, Salmonella spp exhibited a similar persistence to E. coli in aquatic ecosystems, particularly in marine environment.
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Rojas-Alfaro, Rebeca, Rodolfo Umaña-Castro, Norman Rojas-Campos e Maribel Vargas-Montero. "Primer reporte de bacterias y dinoflagelados marinos luminiscentes del Parque Nacional Isla del Coco, Costa Rica". Revista de Biología Tropical 68, S1 (24 de março de 2020): S213—S224. http://dx.doi.org/10.15517/rbt.v68is1.41182.

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Introducción: La bioluminiscencia es la capacidad de ciertos organismos para transformar la energía química en energía lumínica mediante varios procesos bioquímicos. Objetivo: el aislamiento e identificación por primera vez de bacterias luminiscentes en agua marina superficial y la identificación de dinoflagelados luminiscentes marinos del Parque Nacional Isla del Coco, Costa Rica. Metodología: Se colectaron muestras de agua marina obtenida por buceo a 20 m y a nivel superficial de 13 sitios en la Isla del Coco, Costa Rica. Por otra parte, se analizaron muestras de fitoplancton colectadas desde la superficie hasta los 30 m de profundudad en los alrededores de 8 sitios de la Isla del Coco, y se determinaron varias especies luminiscentes pertenecientes a los géneros Ornithocercus y Ceratocorys. Resultados: Se logró obtener 7 aislados bacterianos luminiscentes, se identificaron y caracterizaron bioquímicamente mediante una plataforma automatizada (Vitek) con altos niveles de confianza, se ubicaron taxonómicamente dentro del género Vibrio, 2 especies: V. alginolyticus y V. parahaemolyticus, además, algunos aislados presentaron resistencia al antibiótico ampicilina y 100% capacidad hemolítica. Esta investigación muestra evidencia de la presencia de especies microscópicas marinas en Isla del Coco, Costa Rica, capaces de presentar el fenómeno de la luminiscencia, por lo que profundizar en su estudio sería relevante en cuanto a la importancia de estos microorganismos en la producción de metabolitos secundarios y como indicadores de floraciones algales nocivas, por lo que se hace necesario realizar más investigación científica para determinar su potencial biotecnológico. Conclusiones: De la misma forma, los resultados obtenidos en esta investigación sugieren expandir las localidades de colecta y aislamientos de microorganismos luminiscentes, acompañado de una caracterización bioquímica y molecular, con el fin de explorar la diversidad microbiana asociada a eventos de luminiscencia y determinar los ambientes en el que estas especies se desarrollan.
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Abdalla, Ehab Omer, Mohammed Taha Abdalla Shigidi, Hassan Khalid Elsubki e Nahid Abdel Rahim Osman. "Antimicrobial activity of methanolic extracts of selected marine macroalgae against some pathogenic microorganisms". Journal of Coastal Life Medicine 4, n.º 5 (maio de 2016): 364–67. http://dx.doi.org/10.12980/jclm.4.2016j6-46.

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Wang, Fengping, Meng Li, Li Huang e Xiao-Hua Zhang. "Cultivation of uncultured marine microorganisms". Marine Life Science & Technology 3, n.º 2 (15 de março de 2021): 117–20. http://dx.doi.org/10.1007/s42995-021-00093-z.

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KOBAYASHI, Jun'ichi, Masarni ISHIBASHI e Hideyuki SHIGEMORI. "Bioactive Substances from Marine Microorganisms." Journal of Synthetic Organic Chemistry, Japan 50, n.º 9 (1992): 772–85. http://dx.doi.org/10.5059/yukigoseikyokaishi.50.772.

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URAKAWA, HIDETOSHI. "Molecular ecology of marine microorganisms". NIPPON SUISAN GAKKAISHI 72, n.º 5 (2006): 811–14. http://dx.doi.org/10.2331/suisan.72.811.

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Javed, Faraza, M. Imran Qadir, Khalid Hussain Janbaz e Muhammad Ali. "Novel drugs from marine microorganisms". Critical Reviews in Microbiology 37, n.º 3 (20 de maio de 2011): 245–49. http://dx.doi.org/10.3109/1040841x.2011.576234.

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KELECOM, ALPHONSE. "Secondary metabolites from marine microorganisms". Anais da Academia Brasileira de Ciências 74, n.º 1 (março de 2002): 151–70. http://dx.doi.org/10.1590/s0001-37652002000100012.

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After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.
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Cottrell, Matthew T., Jessica A. Moore e David L. Kirchman. "Chitinases from Uncultured Marine Microorganisms". Applied and Environmental Microbiology 65, n.º 6 (1 de junho de 1999): 2553–57. http://dx.doi.org/10.1128/aem.65.6.2553-2557.1999.

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ABSTRACT Our understanding of the degradation of organic matter will benefit from a greater appreciation for the genes encoding enzymes involved in the hydrolysis of biopolymers such as chitin, one of the most abundant polymers in nature. To isolate representative and abundant chitinase genes from uncultivated marine bacteria, we constructed libraries of genomic DNA isolated from coastal and estuarine waters. The libraries were screened for genes encoding proteins that hydrolyze a fluorogenic analogue of chitin, 4-methylumbelliferyl β-d-N,N′-diacetylchitobioside (MUF-diNAG). The abundance of clones capable of MUF-diNAG hydrolysis was higher in the library constructed with DNA from the estuary than in that constructed with DNA from coastal waters, although the abundance of positive clones was also dependent on the method used to screen the library. Plaque assays revealed nine MUF-diNAG-positive clones of 75,000 screened for the estuarine sample and two clones of 750,000 for the coastal sample. A microtiter plate assay revealed approximately 1 positive clone for every 500 clones screened in the coastal library. The number of clones detected with the plaque assay was consistent with estimates of the portion of culturable bacteria that degrade chitin. Our results suggest that culture-dependent methods do not greatly underestimate the portion of marine bacterial communities capable of chitin degradation.
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Habbu, Prasanna, Vijayanand Warad, Rajesh Shastri, Smita Madagundi e Venkatrao H. Kulkarni. "Antimicrobial metabolites from marine microorganisms". Chinese Journal of Natural Medicines 14, n.º 2 (fevereiro de 2016): 101–16. http://dx.doi.org/10.1016/s1875-5364(16)60003-1.

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C., Pedrós-Alió, e Simó R. "Studying marine microorganisms from space". International Microbiology 5, n.º 4 (1 de dezembro de 2002): 195–200. http://dx.doi.org/10.1007/s10123-002-0087-7.

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Hentschel, Ute. "Natural Products from Marine Microorganisms". ChemBioChem 3, n.º 11 (4 de novembro de 2002): 1151–54. http://dx.doi.org/10.1002/1439-7633(20021104)3:11<1151::aid-cbic1151>3.0.co;2-5.

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Yamazaki, Yoshimitsu, Akihiko Maruyama, Kuniaki Hosono, Takanori Higashihara e Harumi Kobayash. "Asymmetrie Reduction of Synthetic Ketones by Marine Microorganisms". Zeitschrift für Naturforschung C 48, n.º 5-6 (1 de junho de 1993): 451–56. http://dx.doi.org/10.1515/znc-1993-5-609.

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Abstract Three strains of bacteria reducing (trifluoroacetyl)ferrocene (3) to optically pure (R)-2,2,2-trifluoro-l-hydroxyethylferrocene (4) and one bacterial strain reducing 3 to (S)-4 of moderate optical purity were isolated from sea-water collected at the coastal areas in Ibaraki prefecture of Japan. The former three strains were identified as Micrococcus lylae, Micrococcus luteus, and Deleya marina and the latter as Bacillus licheniformis. These strains also asymmetrically reduced some other synthetic ketones, e.g., 2,2,2-trifluoroacetophenone (7) and phenyl trimethylsilyl ketone (9). Further screening of microorganisms capable of reducing 3 was done with bacteria isolated from sea-water of the deep sea (Okinawa trough, Japan trench, and Mariana trough) and of the pelagic areas (Indian Ocean and South China Sea). Most of these marine strains preferentially reduced 3 to (R)-4 similar to the coastal strains, but the frequency of finding very highly enantioselective strains (i.e., those forming 4 of > 90% e.e.) was remark­ ably high in several sites of the deep sea and pelagic areas as compared with the coast and terrestrial environment.
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González-Toril, E., R. Amils, R. J. Delmas, J. R. Petit, J. Komárek e J. Elster. "Bacterial diversity of autotrophic enriched cultures from remote, glacial Antarctic, Alpine and Andean aerosol, snow and soil samples". Biogeosciences 6, n.º 1 (8 de janeiro de 2009): 33–44. http://dx.doi.org/10.5194/bg-6-33-2009.

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Abstract. Four different communities and one culture of autotrophic microbial assemblages were obtained by incubation of samples collected from high elevation snow in the Alps (Mt. Blanc area) and the Andes (Nevado Illimani summit, Bolivia), from Antarctic aerosol (French station Dumont d'Urville) and a maritime Antarctic soil (King George Island, South Shetlands, Uruguay Station Artigas), in a minimal mineral (oligotrophic) media. Molecular analysis of more than 200 16S rRNA gene sequences showed that all cultured cells belong to the Bacteria domain. Phylogenetic comparison with the currently available rDNA database allowed sequences belonging to Proteobacteria Alpha-, Beta- and Gamma-proteobacteria), Actinobacteria and Bacteroidetes phyla to be identified. The Andes snow culture was the richest in bacterial diversity (eight microorganisms identified) and the marine Antarctic soil the poorest (only one). Snow samples from Col du Midi (Alps) and the Andes shared the highest number of identified microorganisms (Agrobacterium, Limnobacter, Aquiflexus and two uncultured Alphaproteobacteria clones). These two sampling sites also shared four sequences with the Antarctic aerosol sample (Limnobacter, Pseudonocardia and an uncultured Alphaproteobacteriaclone). The only microorganism identified in the Antarctica soil (Brevundimonas sp.) was also detected in the Antarctic aerosol. Most of the identified microorganisms had been detected previously in cold environments, marine sediments soils and rocks. Air current dispersal is the best model to explain the presence of very specific microorganisms, like those identified in this work, in environments very distant and very different from each other.
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Na, Hengyuan, Dong Liu e Shengsheng Wang. "An Attention-Based Uncertainty Revising Network with Multi-Loss for Environmental Microorganism Segmentation". Electronics 12, n.º 3 (2 de fevereiro de 2023): 763. http://dx.doi.org/10.3390/electronics12030763.

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The presence of environmental microorganisms is inevitable in our surroundings, and segmentation is essential for researchers to identify, understand, and utilize the microorganisms; make use of their benefits; and prevent harm. However, the segmentation of environmental microorganisms is challenging because their vague margins are almost transparent compared with those of the environment. In this study, we propose a network with an uncertainty feedback module to find ambiguous boundaries and regions and an attention module to localize the major region of the microorganism. Furthermore, we apply a mid-pred module to output low-resolution segmentation results directly from decoder blocks at each level. This module can help the encoder and decoder capture details from different scales. Finally, we use multi-loss to guide the training. Rigorous experimental evaluations on the benchmark dataset demonstrate that our method achieves higher scores than other sophisticated network models (95.63% accuracy, 89.90% Dice, 81.65% Jaccard, 94.68% recall, 0.59 ASD, 2.24 HD95, and 85.58% precision) and outperforms them.
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Uetake, Jun, Thomas C. J. Hill, Kathryn A. Moore, Paul J. DeMott, Alain Protat e Sonia M. Kreidenweis. "Airborne bacteria confirm the pristine nature of the Southern Ocean boundary layer". Proceedings of the National Academy of Sciences 117, n.º 24 (1 de junho de 2020): 13275–82. http://dx.doi.org/10.1073/pnas.2000134117.

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Microorganisms are ubiquitous and highly diverse in the atmosphere. Despite the potential impacts of airborne bacteria found in the lower atmosphere over the Southern Ocean (SO) on the ecology of Antarctica and on marine cloud phase, no previous region-wide assessment of bioaerosols over the SO has been reported. We conducted bacterial profiling of boundary layer shipboard aerosol samples obtained during an Austral summer research voyage, spanning 42.8 to 66.5°S. Contrary to findings over global subtropical regions and the Northern Hemisphere, where transport of microorganisms from continents often controls airborne communities, the great majority of the bacteria detected in our samples were marine, based on taxonomy, back trajectories, and source tracking analysis. Further, the beta diversity of airborne bacterial communities varied with latitude and temperature, but not with other meteorological variables. Limited meridional airborne transport restricts southward community dispersal, isolating Antarctica and inhibiting microorganism and nutrient deposition from lower latitudes to these same regions. A consequence and implication for this region’s marine boundary layer and the clouds that overtop it is that it is truly pristine, free from continental and anthropogenic influences, with the ocean as the dominant source controlling low-level concentrations of cloud condensation nuclei and ice nucleating particles.
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Paul, Valerie J., Christopher J. Freeman e Vinayak Agarwal. "Chemical Ecology of Marine Sponges: New Opportunities through “-Omics”". Integrative and Comparative Biology 59, n.º 4 (27 de abril de 2019): 765–76. http://dx.doi.org/10.1093/icb/icz014.

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Abstract The chemical ecology and chemical defenses of sponges have been investigated for decades; consequently, sponges are among the best understood marine organisms in terms of their chemical ecology, from the level of molecules to ecosystems. Thousands of natural products have been isolated and characterized from sponges, and although relatively few of these compounds have been studied for their ecological functions, some are known to serve as chemical defenses against predators, microorganisms, fouling organisms, and other competitors. Sponges are hosts to an exceptional diversity of microorganisms, with almost 40 microbial phyla found in these associations to date. Microbial community composition and abundance are highly variable across host taxa, with a continuum from diverse assemblages of many microbial taxa to those that are dominated by a single microbial group. Microbial communities expand the nutritional repertoire of their hosts by providing access to inorganic and dissolved sources of nutrients. Not only does this continuum of microorganism–sponge associations lead to divergent nutritional characteristics in sponges, these associated microorganisms and symbionts have long been suspected, and are now known, to biosynthesize some of the natural products found in sponges. Modern “omics” tools provide ways to study these sponge–microbe associations that would have been difficult even a decade ago. Metabolomics facilitate comparisons of sponge compounds produced within and among taxa, and metagenomics and metatranscriptomics provide tools to understand the biology of host–microbe associations and the biosynthesis of ecologically relevant natural products. These combinations of ecological, microbiological, metabolomic and genomics tools, and techniques provide unprecedented opportunities to advance sponge biology and chemical ecology across many marine ecosystems.
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Pinedo-Rivilla, Cristina, Josefina Aleu e Rosa Durán-Patrón. "Cryptic Metabolites from Marine-Derived Microorganisms Using OSMAC and Epigenetic Approaches". Marine Drugs 20, n.º 2 (18 de janeiro de 2022): 84. http://dx.doi.org/10.3390/md20020084.

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Marine microorganisms have proven to be a source of new natural products with a wide spectrum of biological activities relevant in different industrial sectors. The ever-increasing number of sequenced microbial genomes has highlighted a discrepancy between the number of gene clusters potentially encoding the production of natural products and the actual number of chemically characterized metabolites for a given microorganism. Homologous and heterologous expression of these biosynthetic genes, which are often silent under experimental laboratory culture conditions, may lead to the discovery of new cryptic natural products of medical and biotechnological interest. Several new genetic and cultivation-based strategies have been developed to meet this challenge. The OSMAC approach (one strain—many compounds), based on modification of growth conditions, has proven to be a powerful strategy for the discovery of new cryptic natural products. As a direct extension of this approach, the addition of chemical elicitors or epigenetic modifiers have also been used to activate silent genes. This review looks at the structures and biological activities of new cryptic metabolites from marine-derived microorganisms obtained using the OSMAC approach, the addition of chemical elicitors, and enzymatic inhibitors and epigenetic modifiers. It covers works published up to June 2021.
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Zhao, Yanchen, Liyun Guo, Yu Xia, Xiyi Zhuang e Weihua Chu. "Isolation, Identification of Carotenoid-Producing Rhodotorula sp. from Marine Environment and Optimization for Carotenoid Production". Marine Drugs 17, n.º 3 (8 de março de 2019): 161. http://dx.doi.org/10.3390/md17030161.

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Carotenoids are natural pigments found in plants and microorganisms. These important nutrients play significant roles in animal health. In contrast to plant production, the advantages of microbial fermentation of carotenoids are the lower media costs, fast growth rate of microorganisms, and the ease of culture condition control. In this study, a colony of red pigment-producing yeast, Rhodotorula sp. RY1801, was isolated from the sediment of marine environment with the potential to produce carotenoids. Optimization of carotenoid production in Rhodotorula sp. RY1801 was also discussed. The optimum conditions found for carotenoid production were as follows: temperature, 28 °C; pH 5.0; carbon source, 10 g/L glucose, nitrogen source, 10 g/L yeast extract, maximum concentration of 987 µg/L of total carotenoids was obtained. The results of this study show that the isolated yeast strain Rhodotorula sp. RY1801 can potentially be used in future as a promising microorganism for the commercial production of carotenoids.
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Blanco -Jarvio, A., A. Martínez -López e A. Bautista -García. "OPTIMIZACIÓN DE UN PROTOCOLO DE EXTRACCIÓN DE DNA TOTAL PARA LA AMPLIFICACIÓN DE MARCADORES MOLECULARES FUNCIONALES ESPECÍFICOS DE ORGANISMOS DESNITRIFICANTES". CICIMAR Oceánides 29, n.º 2 (1 de dezembro de 2014): 37. http://dx.doi.org/10.37543/oceanides.v29i2.138.

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En esta contribución se planteó el objetivo de resolver la problemática que se enfrenta al trabajar con técnicas de biología molecular para la extracción de DNA obtenido de material particulado marino en suspensión, y se presenta un propuesta de cómo pueden ser resueltos estos problemas. Los protocolos comúnmente empleados fueron modificados para optimizar la cantidad de DNA total extraído, incrementado así la probabilidad de la amplificación de genes funcionales. Se presentan, además, resultados de la selección de sitios hipervariables para el 16S rRNA, así como para los genes nirS, nirK y nosZ para determinación de amplicones útiles en la identificación de microorganismos participantes en la ruta de desnitrificación en la columna de agua. Protocol optimization for DNA extraction and amplification by PCR of denitrifying organisms In this contribution we had the objective to solve the problems encountered working with molecular biology techniques for the extraction of DNA obtained from marine suspended particulate matter, and we provide an alternative on how to resolve such problems. Commonly employed protocols were modified to optimize the total DNA extracted increasing in terms of quality and quantity the probability of amplifying the functional genes. In addition, the results of the selection of hypervariable sites of 16S rARN and nirS, nirK and nosZ genes are presented for the determination of amplicons useful in the identification of microorganisms participating in the denitrification pathway in the water column
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Blanco -Jarvio, A., A. Martínez -López e A. Bautista -García. "OPTIMIZACIÓN DE UN PROTOCOLO DE EXTRACCIÓN DE DNA TOTAL PARA LA AMPLIFICACIÓN DE MARCADORES MOLECULARES FUNCIONALES ESPECÍFICOS DE ORGANISMOS DESNITRIFICANTES". CICIMAR Oceánides 29, n.º 2 (1 de dezembro de 2014): 37. http://dx.doi.org/10.37543/oceanides.v29i2.138.

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En esta contribución se planteó el objetivo de resolver la problemática que se enfrenta al trabajar con técnicas de biología molecular para la extracción de DNA obtenido de material particulado marino en suspensión, y se presenta un propuesta de cómo pueden ser resueltos estos problemas. Los protocolos comúnmente empleados fueron modificados para optimizar la cantidad de DNA total extraído, incrementado así la probabilidad de la amplificación de genes funcionales. Se presentan, además, resultados de la selección de sitios hipervariables para el 16S rRNA, así como para los genes nirS, nirK y nosZ para determinación de amplicones útiles en la identificación de microorganismos participantes en la ruta de desnitrificación en la columna de agua. Protocol optimization for DNA extraction and amplification by PCR of denitrifying organisms In this contribution we had the objective to solve the problems encountered working with molecular biology techniques for the extraction of DNA obtained from marine suspended particulate matter, and we provide an alternative on how to resolve such problems. Commonly employed protocols were modified to optimize the total DNA extracted increasing in terms of quality and quantity the probability of amplifying the functional genes. In addition, the results of the selection of hypervariable sites of 16S rARN and nirS, nirK and nosZ genes are presented for the determination of amplicons useful in the identification of microorganisms participating in the denitrification pathway in the water column
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Zhao, Xin-Qing. "Genome-Based Studies of Marine Microorganisms to Maximize the Diversity of Natural Products Discovery for Medical Treatments". Evidence-Based Complementary and Alternative Medicine 2011 (2011): 1–11. http://dx.doi.org/10.1155/2011/384572.

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Marine microorganisms are rich source for natural products which play important roles in pharmaceutical industry. Over the past decade, genome-based studies of marine microorganisms have unveiled the tremendous diversity of the producers of natural products and also contributed to the efficiency of harness the strain diversity and chemical diversity, as well as the genetic diversity of marine microorganisms for the rapid discovery and generation of new natural products. In the meantime, genomic information retrieved from marine symbiotic microorganisms can also be employed for the discovery of new medical molecules from yet-unculturable microorganisms. In this paper, the recent progress in the genomic research of marine microorganisms is reviewed; new tools of genome mining as well as the advance in the activation of orphan pathways and metagenomic studies are summarized. Genome-based research of marine microorganisms will maximize the biodiscovery process and solve the problems of supply and sustainability of drug molecules for medical treatments.
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Sáenz-Arias, Sol, Ostin Garcés-Ordóñez, Tania Córdoba-Meza, Lina Blandon, Luisa Espinosa Díaz, Lizbeth Vivas-Aguas e Miquel Canals. "Contaminación por vertidos de aguas residuales: Una revisión de las interacciones microorganismos–microplásticos y sus posibles riesgos ambientales en aguas costeras colombianas". Ecosistemas 32, n.º 1 (29 de abril de 2023): 2489. http://dx.doi.org/10.7818/ecos.2489.

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Los vertidos de aguas residuales en los ecosistemas acuáticos son fuente de microplásticos y microorganismos patógenos, que afectan la calidad ambiental y representan un riesgo para la biodiversidad y la salud humana. Los objetivos de esta revisión fueron: (i) analizar los impactos de los vertimientos de aguas residuales sobre la calidad sanitaria de aguas costeras de Colombia, y (ii) examinar los posibles riesgos ambientales de las interacciones entre microorganismos–microplásticos. Durante el 2021, en el marco del monitoreo ambiental marino de Colombia se midieron los coliformes termotolerantes–CTE y los enterococos fecales–EFE en muestras de agua marina superficial en 128 estaciones, registrándose concentraciones de 2–704 000 NMP de CTE/100 mL y de 1–3360 UFC de EFE/100 mL. Los municipios con mayor impacto sobre la calidad sanitaria del agua marina fueron Santa Marta (Caribe) y Tumaco (Pacífico). En relación con lo anterior, se revisaron 84 documentos sobre contaminación microbiológica e interacciones microorganismos–microplásticos en aguas costeras publicados entre 2005 y febrero/2021, examinando aspectos metodológicos, grupos microbianos más comunes, interacciones microorganismos–microplásticos y sus riesgos ambientales. En Colombia existen riesgos asociados a la contaminación microbiológica y por microplásticos en las aguas costeras que requieren atención. Es necesario mejorar la gestión de residuos; la investigación/monitoreo de las comunidades microbianas, sus genes de resistencia/virulencia; y las interacciones de dichas comunidades con los microplásticos y otros organismos comercialmente importantes.
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Wang, Lijun, Xiaofei Lu, Zhikai Xing, Xindong Teng, Shuang Wang, Tianyi Liu, Li Zheng, Xumin Wang e Jiangyong Qu. "Macrogenomics Reveals Effects on Marine Microbial Communities during Oplegnathus punctatus Enclosure Farming". Biology 13, n.º 8 (15 de agosto de 2024): 618. http://dx.doi.org/10.3390/biology13080618.

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(1) Background: Laizhou Bay is an important aquaculture area in the north of China. Oplegnathus punctatus is one of the species with high economic benefits. In recent years, the water environment of Laizhou Bay has reached a mild eutrophication level, while microorganisms are an important group between the environment and species. In this study, we evaluated alterations in environmental elements, microbial populations, and antibiotic resistance genes (ARGs) along with their interconnections during Oplegnathus punctatus net culture. (2) Methods: A total of 142 samples from various water layers were gathered for metagenome assembly analysis. Mariculture increases the abundance of microorganisms in this culture area and makes the microbial community structure more complex. The change had more significant effects on sediment than on seawater. (3) Results: Certain populations of cyanobacteria and Candidatus Micrarchaecta in seawater, and Actinobacteria and Thaumarchaeota in sediments showed high abundance in the mariculture area. Antibiotic resistance genes in sediments were more sensitive to various environmental factors, especially oxygen solubility and salinity. (4) Conclusions: These findings highlight the complex and dynamic nature of microorganism–environment–ARG interactions, characterized by regional specificity and providing insights for a more rational use of marine resources.
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Baharum, S. N., E. K. Beng e M. A. A. Mokhtar. "Marine Microorganisms: Potential Application and Challenges". Journal of Biological Sciences 10, n.º 6 (1 de agosto de 2010): 555–64. http://dx.doi.org/10.3923/jbs.2010.555.564.

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Shizuri, Yoshikazu. "Natural Products from Marine Derived Microorganisms". Journal of Synthetic Organic Chemistry, Japan 68, n.º 5 (2010): 534–42. http://dx.doi.org/10.5059/yukigoseikyokaishi.68.534.

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Arrigo, Kevin R. "Marine microorganisms and global nutrient cycles". Nature 437, n.º 7057 (14 de setembro de 2004): 349–55. http://dx.doi.org/10.1038/nature04159.

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KOBAYASHI, Jun'ichi, e Masami ISHIBASHI. "Bioactive Substances from Symbiotic Marine Microorganisms". Kagaku To Seibutsu 37, n.º 5 (1999): 316–23. http://dx.doi.org/10.1271/kagakutoseibutsu1962.37.316.

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Chen, Gang, Hai-Feng Wang e Yue-Hu Pei. "Secondary metabolites from marine-derived microorganisms". Journal of Asian Natural Products Research 16, n.º 1 (11 de novembro de 2013): 105–22. http://dx.doi.org/10.1080/10286020.2013.855202.

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Kobayashi, Junichi, e Masami Ishibashi. "Bioactive metabolites of symbiotic marine microorganisms". Chemical Reviews 93, n.º 5 (julho de 1993): 1753–69. http://dx.doi.org/10.1021/cr00021a005.

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Andryukov, B. G., V. V. Mikhaylov, N. N. Besednova, T. S. Zaporozhets, M. P. Bynina e E. V. Matosova. "The Bacteriocinogenic Potential of Marine Microorganisms". Russian Journal of Marine Biology 44, n.º 6 (novembro de 2018): 433–41. http://dx.doi.org/10.1134/s1063074018060020.

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Sashchuk, O. V., T. V. Gudzenko e V. O. Ivanytsia. "MICROORGANISMS OF MARINE COLD HYDROCARBON SEEPS". Microbiology&Biotechnology, n.º 2(61) (20 de setembro de 2024): 6–27. http://dx.doi.org/10.18524/2307-4663.2024.2(61).310552.

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Marine hydrocarbon seeps, due to their unique geophysical and geochemical characteristics, form unique conditions for the development of specific microbial communities. Diverse and interconnected metabolic activities of them underlie global ecological processes. In this review were considered the geophysical and chemical conditions for the formation of seepages and hydrocarbon fluids – energy sources and substrates for metabolic processes mediated by microorganisms that exist in these ecological niches. It was presented the information about microbial biodiversity in cold hydrocarbon seeps, its metabolic potential in conditions of dynamic environmental development.
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Gang, Yehui, Tae-Yang Eom, Svini Dileepa Marasinghe, Youngdeuk Lee, Eunyoung Jo e Chulhong Oh. "Optimising the DPPH Assay for Cell-Free Marine Microorganism Supernatants". Marine Drugs 19, n.º 5 (29 de abril de 2021): 256. http://dx.doi.org/10.3390/md19050256.

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Antioxidants prevent ageing and are usually quantified and screened using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. However, this assay cannot be used for salt-containing samples, such as the cell-free supernatants of marine microorganisms that are aggregated under these conditions. Herein, the DPPH solvent (methanol or ethanol) and its water content were optimized to enable the analysis of salt-containing samples, aggregation was observed for alcohol contents of >70%. The water content of methanol influenced the activities of standard antioxidants but did not significantly affect that of the samples. Based on solution stability considerations, 70% aqueous methanol was chosen as the optimal DPPH solvent. The developed method was successfully applied to the cell-free supernatants of marine bacteria (Pseudoalteromonas rubra and Pseudoalteromonas xiamenensis), revealing their high antioxidant activities. Furthermore, it was concluded that this method would be useful for the screening of marine microorganism–derived antioxidants, which also has numerous potential applications, such as salt-fermented foods.
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Zakaria, N. N., A. F. A. Roslee, C. Gomez-Fuentes, A. Zulkharnain, M. Abdulrasheed, S. Sabri, N. Ramírez-Moreno, N. Calisto-Ulloa e S. A. Ahmad. "Kinetic studies of marine psychrotolerant microorganisms capable of degrading diesel in the presence of heavy metals". Revista Mexicana de Ingeniería Química 19, n.º 3 (1 de março de 2020): 1375–88. http://dx.doi.org/10.24275/rmiq/bio1072.

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Oberbeckmann, Sonja, e Matthias Labrenz. "Marine Microbial Assemblages on Microplastics: Diversity, Adaptation, and Role in Degradation". Annual Review of Marine Science 12, n.º 1 (3 de janeiro de 2020): 209–32. http://dx.doi.org/10.1146/annurev-marine-010419-010633.

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We have known for more than 45 years that microplastics in the ocean are carriers of microbially dominated assemblages. However, only recently has the role of microbial interactions with microplastics in marine ecosystems been investigated in detail. Research in this field has focused on three main areas: ( a) the establishment of plastic-specific biofilms (the so-called plastisphere); ( b) enrichment of pathogenic bacteria, particularly members of the genus Vibrio, coupled to a vector function of microplastics; and ( c) the microbial degradation of microplastics in the marine environment. Nevertheless, the relationships between marine microorganisms and microplastics remain unclear. In this review, we deduce from the current literature, new comparative analyses, and considerations of microbial adaptation concerning plastic degradation that interactions between microorganisms and microplastic particles should have rather limited effects on the ocean ecosystems. The majority of microorganisms growing on microplastics seem to belong to opportunistic colonists that do not distinguish between natural and artificial surfaces. Thus, microplastics do not pose a higher risk than natural particles to higher life forms by potentially harboring pathogenic bacteria. On the other hand, microplastics in the ocean represent recalcitrant substances for microorganisms that are insufficient to support prokaryotic metabolism and will probably not be microbially degraded in any period of time relevant to human society. Because we cannot remove microplastics from the ocean, proactive action regarding research on plastic alternatives and strategies to prevent plastic entering the environment should be taken promptly.
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Romano, Stefano, Stephen Jackson, Sloane Patry e Alan Dobson. "Extending the “One Strain Many Compounds” (OSMAC) Principle to Marine Microorganisms". Marine Drugs 16, n.º 7 (23 de julho de 2018): 244. http://dx.doi.org/10.3390/md16070244.

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Genomic data often highlights an inconsistency between the number of gene clusters identified using bioinformatic approaches as potentially producing secondary metabolites and the actual number of chemically characterized secondary metabolites produced by any given microorganism. Such gene clusters are generally considered as “silent”, meaning that they are not expressed under laboratory conditions. Triggering expression of these “silent” clusters could result in unlocking the chemical diversity they control, allowing the discovery of novel molecules of both medical and biotechnological interest. Therefore, both genetic and cultivation-based techniques have been developed aimed at stimulating expression of these “silent” genes. The principles behind the cultivation based approaches have been conceptualized in the “one strain many compounds” (OSMAC) framework, which underlines how a single strain can produce different molecules when grown under different environmental conditions. Parameters such as, nutrient content, temperature, and rate of aeration can be easily changed, altering the global physiology of a microbial strain and in turn significantly affecting its secondary metabolism. As a direct extension of such approaches, co-cultivation strategies and the addition of chemical elicitors have also been used as cues to activate “silent” clusters. In this review, we aim to provide a focused and comprehensive overview of these strategies as they pertain to marine microbes. Moreover, we underline how changes in some parameters which have provided important results in terrestrial microbes, but which have rarely been considered in marine microorganisms, may represent additional strategies to awaken “silent” gene clusters in marine microbes. Unfortunately, the empirical nature of the OSMAC approach forces scientists to perform extensive laboratory experiments. Nevertheless, we believe that some computation and experimental based techniques which are used in other disciplines, and which we discuss; could be effectively employed to help streamline the OSMAC based approaches. We believe that natural products discovery in marine microorganisms would be greatly aided through the integration of basic microbiological approaches, computational methods, and technological innovations, thereby helping unearth much of the as yet untapped potential of these microorganisms.
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