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101.
Marcelo Magioli Katia Maria Paschoaletto Micchi de Barros Ferraz Eleonore Zulnara Freire Setz Alexandre Reis Percequillo Michelle Viviane de Sá Santos Rondon Vanessa Villanova Kuhnen Mariana Cristina da Silva Canhoto Karen Evelyn Almeida dos Santos Claudia Zukeran Kanda Gabriela de Lima Fregonezi Helena Alves do Prado Mitra Katherina Ferreira Milton Cezar Ribeiro Priscilla Marqui Schmidt Villela Luiz Lehmann Coutinho Márcia Gonçalves Rodrigues 《European Journal of Wildlife Research》2016,62(4):431-446
102.
Cooperation of Aspergillus nidulans enzymes increases plant polysaccharide saccharification
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Robson Tramontina Diogo Robl Gabriela Piccolo Maitan‐Alfenas Ronald P. de Vries 《Biotechnology journal》2016,11(7):988-992
Efficient polysaccharide degradation depends on interaction between enzymes acting on the main chain and the side chains. Previous studies demonstrated cooperation between several enzymes, but not all enzyme combinations have been explored. A better understanding of enzyme cooperation would enable the design of better enzyme mixtures, optimally profiting from synergistic effects. In this study, we analyzed the cooperation of several enzymes involved in the degradation of xylan, glucan, xyloglucan and crude plant biomass from Aspergillus nidulans by single and combined incubations with their polymeric substrate. Positive effects were observed between most enzymes, although not always to the same extent. Moreover, the tailor made cocktails formulated in this study resulted in efficient release of glucose from plant biomass. This study also serves as an example for the complex cooperation that occurs between enzymes in plant biomass saccharification and how expression in easily‐accessible hosts, such as Pichia pastoris, can help in revealing these effects. 相似文献
103.
Gabriela Castaño-Meneses 《Arthropod-Plant Interactions》2016,10(5):403-417
The canopy of forests has been considered “the last biotic frontier,” and study of its elements is very important in explaining the global functionality in ecosystems. Epiphytic plants and arthropods are essential elements in canopy habitats, and their relationships have been studied in order to understand the high diversity in tropical forests. Nevertheless, there are few studies on this development in temperate forests. The arthropod community was studied during the rainy and dry seasons at two altitudes, and a total of 240 T. violacea plants of three sizes were collected from Abies religiosa and Quercus spp. host trees. A total of 163,043 arthropods were collected and about 200 morphospecies identified. The highest abundance was obtained during the dry season, while high diversity was found during the rainy season. There was a significant effect of plant size, host trees and collecting season on abundance and diversity, and there were seasonal variations in community composition. The community hosted on A. religiosa epiphytes showed higher abundance and density than that of Quercus. 相似文献
104.
Stefan Schleifenbaum Torsten Prietzel Gabriela Aust Andreas Boldt Sebastian Fritsch Isabel Keil Holger Koch Robert M?bius Holger A. Scheidt Martin F. X. Wagner Niels Hammer 《PloS one》2016,11(3)
Introduction
Though xenogeneic acellular scaffolds are frequently used for surgical reconstruction, knowledge of their mechanical properties is lacking. This study compared the mechanical, histological and ultrastructural properties of various native and acellular specimens.Materials and Methods
Porcine esophagi, ureters and skin were tested mechanically in a native or acellular condition, focusing on the elastic modulus, ultimate tensile stress and maximum strain. The testing protocol for soft tissues was standardized, including the adaption of the tissue’s water content and partial plastination to minimize material slippage as well as templates for normed sample dimensions and precise cross-section measurements. The native and acellular tissues were compared at the microscopic and ultrastructural level with a focus on type I collagens.Results
Increased elastic modulus and ultimate tensile stress values were quantified in acellular esophagi and ureters compared to the native condition. In contrast, these values were strongly decreased in the skin after acellularization. Acellularization-related decreases in maximum strain were found in all tissues. Type I collagens were well-preserved in these samples; however, clotting and a loss of cross-linking type I collagens was observed ultrastructurally. Elastins and fibronectins were preserved in the esophagi and ureters. A loss of the epidermal layer and decreased fibronectin content was present in the skin.Discussion
Acellularization induces changes in the tensile properties of soft tissues. Some of these changes appear to be organ specific. Loss of cross-linking type I collagen may indicate increased mechanical strength due to decreasing transverse forces acting upon the scaffolds, whereas fibronectin loss may be related to decreased load-bearing capacity. Potentially, the alterations in tissue mechanics are linked to organ function and to the interplay of cells and the extracellular matrix, which is different in hollow organs when compared to skin. 相似文献105.
Rafael Conceição de Souza Gabriela de Medeiros Muniz Andrei Santos Siqueira Adonis de Melo Lima Alessandra Pereira da Silva Evonnildo Costa Gonçalves João Lídio da Silva Gonçalves Vianez Júnior 《Journal of molecular modeling》2016,22(11):269
Human immunodeficiency virus (HIV) infections continue to exert an enormous impact on global human health. This led experts to emphasize the importance of new measures for preventing HIV infections, including the development of vaccines and novel drugs. In this context, a promising approach involves the use of lectins that can bind the surface envelope glycoprotein gp120 of HIV with high affinity, preventing viral entry. The cyanobacterial lectin microvirin (MVN) has been proposed as a candidate for development as a topical microbicide because of its ability to bind to high mannose-type glycans, potently inhibiting HIV-1 entry. Thus, the aim of this computational study was to investigate the effects of four point mutations (D53Q, D53E, D53K, and D53W) on the structure and affinity of MVN with di-mannose (MAN). Molecular dynamics simulations followed by binding free energy calculations using MM-GBSA were employed. The calculated binding free energy of ligand-receptor complexation of MVN with MAN was ?26.02 kcal mol-1. We identified in the wild-type protein that residues I45, T59, and Q81 have a major contribution to the binding free energy of di-mannose. Among the investigated mutants, the most promising one was the D53W mutation, with a theoretical binding free energy value of ?29.16 kcal mol-1. We suggest that this increased stability is due to the introduction of extra rigidity on the hinge region connecting two key structural elements of the MVN binding site. 相似文献
106.
107.
Brigitta Ine Van Tussenbroek Tania Valdivia‐Carrillo Irene Teresa Rodríguez‐Virgen Sylvia Nashieli Marisela Sanabria‐Alcaraz Karina Jiménez‐Durán Kor Jent Van Dijk Guadalupe Judith Marquez‐Guzmán 《Ecology and evolution》2016,6(15):5542-5556
The high prevalence of dioecy in marine angiosperms or seagrasses (>50% of all species) is thought to enforce cross‐fertilization. However, seagrasses are clonal plants, and they may still be subject to sibling‐mating or bi‐parental inbreeding if the genetic neighborhood is smaller than the size of the genets. We tested this by determining the genetic neighborhoods of the dioecious seagrass Thalassia testudinum at two sites (Back‐Reef and Mid‐Lagoon) in Puerto Morelos Reef Lagoon, Mexico, by measuring dispersal of pollen and seeds in situ, and by fine‐scale spatial autocorrelation analysis with eight polymorphic microsatellite DNA markers. Prevalence of inbreeding was verified by estimating pairwise kinship coefficients; and by analysing the genotypes of seedlings grown from seeds in mesocosms. Average dispersal of pollen was 0.3–1.6 m (max. 4.8 m) and of seeds was 0.3–0.4 m (max. 1.8 m), resulting in a neighborhood area of 7.4 m2 (range 3.4–11.4 m2) at Back‐Reef and 1.9 (range 1.87–1.92 m2) at Mid‐Lagoon. Neighborhood area (Na) derived from spatial autocorrelation was 0.1–20.5 m2 at Back‐Reef and 0.1–16.9 m2 at Mid‐Lagoon. Maximal extensions of the genets, in 19 × 30 m plots, were 19.2 m (median 7.5 m) and 10.8 m (median 4.8 m) at Back‐Reef and Mid‐Lagoon. There was no indication of deficit or excess of heterozygotes nor were coefficients of inbreeding (FIS) significant. The seedlings did not show statistically significant deficit of heterozygotes (except for 1 locus at Back‐Reef). Contrary to our expectations, we did not find evidence of bi‐parental inbreeding in this dioecious seagrass with large genets but small genetic neighborhoods. Proposed mechanisms to avoid bi‐parental inbreeding are possible selection against homozygotes during fecundation or ovule development. Additionally, the genets grew highly dispersed (aggregation index Ac was 0.09 and 0.10 for Back‐Reef and Mid‐Lagoon, respectively); such highly dispersed guerrilla‐like clonal growth form likely increases the probability of crossing between different potentially unrelated genets. 相似文献
108.
Chiara V. Segré Silvia Senese Sara Loponte Stefano Santaguida Paolo Soffientini Gabriela Grigorean 《MABS-AUSTIN》2016,8(1):37-42
Histone deacetylases (HDACs) are modification enzymes that regulate a plethora of biological processes. HDAC1, a crucial epigenetic modifier, is deregulated in cancer and subjected to a variety of post-translational modifications. Here, we describe the generation of a new monoclonal antibody that specifically recognizes a novel highly dynamic prophase phosphorylation of serine 406-HDAC1, providing a powerful tool for detecting early mitotic cells. 相似文献
109.
Barcoding,population structure,and demographic history of Prodiplosis longifila associated with the Andes
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Sandra M. Velasco‐Cuervo Lizethe L. Espinosa Diana N. Duque‐Gamboa Maria F. Castillo‐Cárdenas Luis M. Hernández Yoan C. Guzmán Maria R. Manzano Nelson Toro‐Perea 《Entomologia Experimentalis et Applicata》2016,158(2):217-227
Prodiplosis longifila Gagné (Diptera: Cecidomyiidae) is an insect pest that attacks various types of crops, including tomato, Solanum lycopersicum L. (Solanaceae), a vegetable with substantial economic significance worldwide. Prodiplosis longifila is a widely distributed pest in Colombia, Ecuador, and Peru, countries characterized by the presence of significant geographic barriers like the Andes Mountains. It has been reported that geographic barriers affect the dynamics and genetic differentiation of insect populations. Therefore, the aim of this study was to assess the diversity, genetic structure, and demographic history of P. longifila through the analysis of sequences within the mitochondrial region of cytochrome oxidase I (COI) and rDNA‐ITS2 in 27 populations located in Colombia and Ecuador. Analyses were performed on populations distributed in three geographic groups separated by the presence of the Andes Mountains. A total of 11 haplotypes were identified with the COI gene and only one haplotype in the rDNA‐ITS2 was found. Analyses of population structure and demographic history revealed that there is a structure associated with the Andes, which is reflected in an uneven distribution of the haplotype frequencies between regions, but even so, gene flow between populations was detected which produces low genetic differentiation. Because P. longifila has a short‐range dispersion that determines its territorial nature, it would be expected that other factors are producing the genetic exchange between populations. We suggest that the anthropogenic effect produced by farming practices, such as the use of seedlings as seed, which may carry P. longifila larvae, cause passive dispersal of pest throughout the Andes, particularly in Colombia. 相似文献
110.