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Del-Claro Kleber Anjos Diego V. Torezan-Silingardi Helena Maura 《Journal of Ethology》2022,40(1):31-36
Journal of Ethology - Facilitation is an ecological interaction in which the presence of one species (e.g., ecosystem engineers) alters the environment in a way that enhances growth, survival or... 相似文献
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Wayllace NZ Valdez HA Merás A Ugalde RA Busi MV Gomez-Casati DF 《Molecular biology reports》2012,39(1):585-591
The metabolic pathways leading to the synthesis of bacterial glycogen involve the action of several enzymes, among which glycogen
synthase (GS) catalyzes the elongation of the α-1,4-glucan. GS from Agrobacterium tumefaciens uses preferentially ADPGlc, although UDPGlc can also be used as glycosyl donor with less efficiency. We present here a continuous
spectrophotometric assay for the determination of GS activity using ADP- or UDPGlc. When ADPGlc was used as the substrate,
the production of ADP is coupled to NADH oxidation via pyruvate kinase (PK) and lactate dehydrogenase (LDH). With UDPGlc as
substrate, UDP was converted to ADP via adenylate kinase and subsequent coupling to PK and LDH reactions. Using this assay,
we determined the kinetic parameters of GS and compared them with those obtained with the classical radiochemical method.
For this purpose, we improved the expression procedure of A. tumefaciens GS using Escherichia coli BL21(DE3)-RIL cells. This assay allows the continuous monitoring of glycosyltransferase activity using ADPGlc or UDPGlc as
sugar-nucleotide donors. 相似文献
76.
Rubn Mateos Fernndez Marko Petek Iryna Gerasymenko Mojca Juterek pela Baebler
Kalyani Kallam Elena Moreno Gimnez Janine Gondolf Alfred Nordmann Kristina Gruden Diego Orzaez Nicola J Patron 《Plant biotechnology journal》2022,20(1):25-36
Arthropod crop pests are responsible for 20% of global annual crop losses, a figure predicted to increase in a changing climate where the ranges of numerous species are projected to expand. At the same time, many insect species are beneficial, acting as pollinators and predators of pest species. For thousands of years, humans have used increasingly sophisticated chemical formulations to control insect pests but, as the scale of agriculture expanded to meet the needs of the global population, concerns about the negative impacts of agricultural practices on biodiversity have grown. While biological solutions, such as biological control agents and pheromones, have previously had relatively minor roles in pest management, biotechnology has opened the door to numerous new approaches for controlling insect pests. In this review, we look at how advances in synthetic biology and biotechnology are providing new options for pest control. We discuss emerging technologies for engineering resistant crops and insect populations and examine advances in biomanufacturing that are enabling the production of new products for pest control. 相似文献
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Mikovski Andréia Izabel da Silva Nayara Tayane Silva Lázara Aline Simões Machado Mariana de Souza Barbosa Lília Cristina Reis Aryane Campos de Matos Elyabe Monteiro Viccini Lyderson Facio da Silva Souza Claudinei Machado Marcelo Dias Otoni Wagner Campos de Carvalho Ilio Fealho Rocha Diego Ismael da Silva Maurecilne Lemes 《Plant Cell, Tissue and Organ Culture》2021,145(2):239-259
Plant Cell, Tissue and Organ Culture (PCTOC) - Somaclonal variation during in vitro culture is often an undesirable phenomenon but may also be a source of genetic variation useful for breeders. The... 相似文献
79.
Magalhães GS Novo JB Clissa PB Della Casa MS Butera D da Silva AM 《Molecular biotechnology》2012,51(2):119-127
Due to its specialized post-translational machinery, mammalian cells represent an interesting and not fully explored system
to express snake toxins. Therefore, in this work, we built up a new mammalian expression vector that enhances the feasibility
to use mammalian cells to express proteins as biomarkers. Among the modifications, an Igκ signal peptide and a 6xHis tag were
inserted into this vector in order to drive the protein to the supernatant and simplify its purification, respectively. In
addition, to facilitate selection of high producing clones and also tag proteins which may function as a biomarker, the sequence
of enhanced green fluorescent protein (EGFP) was added. The efficiency of the resulting vector (pToxEGFP) was tested by cloning
and expressing the viper venom disintegrin echistatin (Ech) that due to its affinity to integrin αvβ3 was tested as a molecular
marker. Expression of EGFP-Ech was achieved in CHO-DXB11 cells resulting in a yield of 22 mg/L. The binding activity of this
chimera protein was successfully achieved on human umbilical vein endothelial cells which highly express αvβ3. The results
indicate that pToxEGFP may constitute an efficient and versatile expression vector to express tagged proteins with potential
biomarker activity. 相似文献
80.
Ruiz-Moreno D Willis BL Page AC Weil E Cróquer A Vargas-Angel B Jordan-Garza AG Jordán-Dahlgren E Raymundo L Harvell CD 《Diseases of aquatic organisms》2012,100(3):249-261
Coral diseases are taking an increasing toll on coral reef structure and biodiversity and are important indicators of declining health in the oceans. We implemented standardized coral disease surveys to pinpoint hotspots of coral disease, reveal vulnerable coral families and test hypotheses about climate drivers from 39 locations worldwide. We analyzed a 3 yr study of coral disease prevalence to identify links between disease and a range of covariates, including thermal anomalies (from satellite data), location and coral cover, using a Generalized Linear Mixed Model. Prevalence of unhealthy corals, i.e. those with signs of known diseases or with other signs of compromised health, exceeded 10% on many reefs and ranged to over 50% on some. Disease prevalence exceeded 10% on 20% of Caribbean reefs and 2.7% of Pacific reefs surveyed. Within the same coral families across oceans, prevalence of unhealthy colonies was higher and some diseases were more common at sites in the Caribbean than those in the Pacific. The effects of high disease prevalence are potentially extensive given that the most affected coral families, the acroporids, faviids and siderastreids, are among the major reef-builders at these sites. The poritids and agaricids stood out in the Caribbean as being the most resistant to disease, even though these families were abundant in our surveys. Regional warm temperature anomalies were strongly correlated with high disease prevalence. The levels of disease reported here will provide a much-needed local reference point against which to compare future change. 相似文献