Prediction,structure characterization,and evolutionary analysis of Erwinia psidii putative type III effectors     

Isadora C. Pereira  Jorge L. Badel  Pedro M. P. Vidigal  Adryelle A. Sousa  Samuel A. Santos  Lúcio M. S. Guimarães  Acelino C. Alfenas 《Plant pathology》2021,70(3):555-566

Erwinia psidii is a gram-negative bacterium that threatens both guava and eucalypt plantations in several countries. Despite the economic importance of both crops, nothing is currently known about the molecular mechanisms underlying E. psidii pathogenicity and, consequently, how it evolved to infect Eucalyptus species besides its presumed native host Psidium guajava. In this study, we predicted putative type III secretion system effectors that may play important roles during plant–E. psidii interactions and conducted effector structure and phylogenetic analyses to gain important insights into their function and evolution. For that, the whole genomes of four E. psidii strains that exhibit differential aggressiveness towards eucalypt clones were sequenced and their effector repertoires predicted based on sequence identity with known effectors of the model phytopathogen Erwinia amylovora. Only proteins sharing significant sequence identity with the DspE and Eop1 effectors were found. Here, it is shown that these two E. psidii effectors retain all structural characteristics of their corresponding protein superfamilies, but exhibit allelic variations that are consistent with the observed aggressiveness differences between strains. Phylogenetic analyses revealed that whereas E. psidii housekeeping gene sequences are more closely related to those from Erwinia tracheiphila, the effector (either nucleotide or amino acid) sequences are more closely related to their Pantoea agglomerans counterparts, suggesting that dspE and eop1 were both acquired through horizontal gene transfer from the latter bacterial species. The results of this study provide important insights on E. psidii pathogenicity and set the stage for future effector functional studies.  相似文献   

Minimum number of measurements for efficient estimation of black spot resistance in papaya genotypes     

de Moraes  Ramon  Vivas  Marcelo  Chagas  José Tiago Barroso  Vivas  Janieli Maganha Silva  da Cruz  Derivaldo Pureza  Pereira  Messias Gonzaga  do Amaral Júnior  Antonio Teixeira 《European journal of plant pathology / European Foundation for Plant Pathology》2021,160(3):637-647

European Journal of Plant Pathology - During a field survey in Tamil Nadu (2014–16), chilli plants showing chlorotic and necrotic ring spots and necrotic streaks on leaves and stems were...  相似文献   

On the Health Benefits vs. Risks of Seaweeds and Their Constituents: The Curious Case of the Polymer Paradigm     

Joo Cotas  Diana Pacheco  Glacio Souza Araujo  Ana Valado  Alan T. Critchley  Leonel Pereira 《Marine drugs》2021,19(3)

To exploit the nutraceutical and biomedical potential of selected seaweed-derived polymers in an economically viable way, it is necessary to analyze and understand their quality and yield fluctuations throughout the seasons. In this study, the seasonal polysaccharide yield and respective quality were evaluated in three selected seaweeds, namely the agarophyte Gracilaria gracilis, the carrageenophyte Calliblepharis jubata (both red seaweeds) and the alginophyte Sargassum muticum (brown seaweed). It was found that the agar synthesis of G. gracilis did not significantly differ with the seasons (27.04% seaweed dry weight (DW)). In contrast, the carrageenan content in C. jubata varied seasonally, being synthesized in higher concentrations during the summer (18.73% DW). Meanwhile, the alginate synthesis of S. muticum exhibited a higher concentration (36.88% DW) during the winter. Therefore, there is a need to assess the threshold at which seaweed-derived polymers may have positive effects or negative impacts on human nutrition. Furthermore, this study highlights the three polymers, along with their known thresholds, at which they can have positive and/or negative health impacts. Such knowledge is key to recognizing the paradigm governing their successful deployment and related beneficial applications in humans.  相似文献   

The Seaweed Diet in Prevention and Treatment of the Neurodegenerative Diseases     

Leonel Pereira  Ana Valado 《Marine drugs》2021,19(3)

Edible marine algae are rich in bioactive compounds and are, therefore, a source of bioavailable proteins, long chain polysaccharides that behave as low-calorie soluble fibers, metabolically necessary minerals, vitamins, polyunsaturated fatty acids, and antioxidants. Marine algae were used primarily as gelling agents and thickeners (phycocolloids) in food and pharmaceutical industries in the last century, but recent research has revealed their potential as a source of useful compounds for the pharmaceutical, medical, and cosmetic industries. The green, red, and brown algae have been shown to have useful therapeutic properties in the prevention and treatment of neurodegenerative diseases: Parkinson, Alzheimer’s, and Multiple Sclerosis, and other chronic diseases. In this review are listed and described the main components of a suitable diet for patients with these diseases. In addition, compounds derived from macroalgae and their neurophysiological activities are described.  相似文献   

Current Knowledge on Microviridin from Cyanobacteria     

Samuel Cavalcante do Amaral  Patrick Romano Monteiro  Joaquim da Silva Pinto Neto  Gustavo Marques Serra  Evonnildo Costa Gonalves  Luciana Pereira Xavier  Agenor Valadares Santos 《Marine drugs》2021,19(1)

Cyanobacteria are a rich source of secondary metabolites with a vast biotechnological potential. These compounds have intrigued the scientific community due their uniqueness and diversity, which is guaranteed by a rich enzymatic apparatus. The ribosomally synthesized and post-translationally modified peptides (RiPPs) are among the most promising metabolite groups derived from cyanobacteria. They are interested in numerous biological and ecological processes, many of which are entirely unknown. Microviridins are among the most recognized class of ribosomal peptides formed by cyanobacteria. These oligopeptides are potent inhibitors of protease; thus, they can be used for drug development and the control of mosquitoes. They also play a key ecological role in the defense of cyanobacteria against microcrustaceans. The purpose of this review is to systematically identify the key characteristics of microviridins, including its chemical structure and biosynthesis, as well as its biotechnological and ecological significance.  相似文献   

Environmental Impact on Seaweed Phenolic Production and Activity: An Important Step for Compound Exploitation     

Silvia Lomartire  Joo Cotas  Diana Pacheco  Joo Carlos Marques  Leonel Pereira  Ana M. M. Gonalves 《Marine drugs》2021,19(5)

Seaweeds are a potential source of bioactive compounds that are useful for biotechnological applications and can be employed in different industrial areas in order to replace synthetic compounds with components of natural origin. Diverse studies demonstrate that there is a solid ground for the exploitation of seaweed bioactive compounds in order to prevent illness and to ensure a better and healthier lifestyle. Among the bioactive algal molecules, phenolic compounds are produced as secondary metabolites with beneficial effects on plants, and also on human beings and animals, due to their inherent bioactive properties, which exert antioxidant, antiviral, and antimicrobial activities. The use of phenolic compounds in pharmaceutical, nutraceutical, cosmetics, and food industries may provide outcomes that could enhance human health. Through the production of healthy foods and natural drugs, bioactive compounds from seaweeds can help with the treatment of human diseases. This review aims to highlight the importance of phenolic compounds from seaweeds, the scope of their production in nature and the impact that these compounds can have on human and animal health through nutraceutical and pharmaceutical products.  相似文献   

Performance of ‘Tahiti’ lime on twelve rootstocks under irrigated and non-irrigated conditions     

Erick Espinoza-Núñez  Francisco de Assis Alves Mourão Filho  Eduardo Sanches Stuchi  Tatiana Cantuarias-Avilés  Carlos Tadeu dos Santos Dias 《Scientia Horticulturae》2011

Faced with new challenges, such as emerging diseases, shortening of orchard longevity, and larger social and environmental demands from consumers, practices such as rootstock diversification, irrigation and high density plantings have become relevant for the Brazilian citrus industry. This research had the objective to evaluate the performance of irrigated and non-irrigated ‘Tahiti’ lime trees grafted on 12 rootstocks and one interstock. Plots were distributed following a randomized block design, with four replicates and one plant per plot. Rootstocks influenced plant vigor, especially ‘Flying Dragon’ trifoliate, which reduced tree height by approximately 47% compared to the ‘Rangpur’ lime. Trees that were budded on more vigorous rootstocks showed higher yield when grown without irrigation than with irrigation. The ‘1646’ citradia and ‘Morton’ citrange rootstocks performed particularly well. On the other hand, the plants on less vigorous rootstocks showed better performance in terms of yield under irrigation than the same combinations without irrigation, especially those grafted on the tetraploid ‘Carrizo’ and ‘Troyer’ citranges, ‘Swingle’ citrumelo, ‘Davis A’ trifoliate and ‘Flying Dragon’ trifoliate. Plants budded on the ‘1708’ citradia had high yields under irrigated and non-irrigated conditions. The effect of interstock on plant vigor was dependent of rootstock. Interstocked plants on ‘Davis A’ trifoliate were higher than those without interstock. On the other hand, interstocked plants on Catania 2 ‘Volkamer’ lemon were less vigorous than those without interstock.  相似文献   

Kinetics of Mercury Bioaccumulation in the Polychaete Hediste diversicolor and in the Bivalve Scrobicularia plana, Through a Dietary Exposure Pathway     

Patricia G. Cardoso  Eduarda Pereira  Tiago F. Grilo  Armando C. Duarte  Miguel A. Pardal 《Water, air, and soil pollution》2012,223(1):421-428

Mercury bioaccumulation kinetics of two important macrobenthic species, the polychaete Hediste diversicolor and the bivalve Scrobicularia plana, were evaluated following a dietary pathway (i.e. contaminated algae), through a mesocosm laboratory experiment. Both studied species presented a similar model of Hg bioaccumulation kinetics, a linear pattern of accumulation through time being the mercury accumulation in the organisms proportional to the mercury concentration in the food. Mercury bioaccumulation rates were higher in the polychaete H. diversicolor (reaching approximately 0.15 μg g⁻¹ at the end of the experiment) than in the bivalve S. plana (≈0.07 μg g⁻¹), which could be related to their feeding strategies, ingestion rates and assimilation efficiencies. Moreover, the mercury bioaccumulation revealed to be quite a fast process especially for the polychaete, and despite the fact that this species is not an edible organism, it is an important prey item, which can greatly contribute to the transport of contaminants to higher trophic levels. Therefore, the bioaccumulation of mercury by these important macrobenthic species, especially the bivalves, represents a non-negligible risk for humans.  相似文献   

Geographical variation and quality assessment of Stryphnodendron adstringens (Mart.) Coville within Brazil     

Valéria S. Corrêa  Antonio L. Cerdeira  Ana L. Fachin  Bianca W. Bertoni  Paulo S. Pereira  Suzelei C. Fran?a  Henrique G. Momm  Rita M. Moraes  Ana M. S. Pereira 《Genetic Resources and Crop Evolution》2012,59(7):1349-1356

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Delineation of specific management areas for coffee cultivation based on the soil–relief relationship and numerical classification     

Maria Gabriela Baracat Sanchez  José Marques Jr.  Diego Silva Siqueira  Livia Arantes Camargo  Gener Tadeu Pereira 《Precision Agriculture》2013,14(2):201-214

Predicting and mapping productivity areas allows crop producers to improve their planning of agricultural activities. The primary aims of this work were the identification and mapping of specific management areas allowing coffee bean quality to be predicted from soil attributes and their relationships to relief. The study area was located in the Southeast of the Minas Gerais state, Brazil. A grid containing a total of 145 uniformly spaced nodes 50 m apart was established over an area of 31.7 ha from which samples were collected at depths of 0.00–0.20 m in order to determine physical and chemical attributes of the soil. These data were analysed in conjunction with plant attributes including production, proportion of beans retained by different sieves and drink quality. The results of principal component analysis (PCA) in combination with geostatistical data showed the attributes clay content and available iron to be the best choices for identifying four crop production environments. Environment A, which exhibited high clay and available iron contents, and low pH and base saturation, was that providing the highest yield (30.4l ha^?1) and best coffee beverage quality (61 sacks ha^?1). Based on the results, we believe that multivariate analysis, geostatistics and the soil–relief relationships contained in the digital elevation model (DEM) can be effectively used in combination for the hybrid mapping of areas of varying suitability for coffee production.  相似文献