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991.
Jean Carlos Rodrigues Silva Luis Henrique Souza Guimarães José Carlos Santos Salgado Rosa Prazeres Melo Furriel Maria Lourdes T. M. Polizeli José César Rosa João Atilio Jorge 《Folia microbiologica》2013,58(6):561-568
Two cellulases from Scytalidium thermophilum were purified and characterized, exhibiting tolerance to glucose and cellobiose. Characterization of purified cellulases I and II by mass spectrometry revealed primary structure similarities with an exoglucanase and an endoglucanase, respectively. Molecular masses were 51.2 and 45.6 kDa for cellulases I and II, respectively, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Cellulases I and II exhibited isoelectric points of 6.2 and 6.9 and saccharide contents of 11 and 93 %, respectively. Optima of temperature and pH were 60–65 °C and 4.0 for purified cellulase I and 65 °C and 6.5 for purified cellulase II. Both cellulases maintained total CMCase activity after 60 min at 60 °C. Cysteine, Mn2+, dithiotreitol and ß-mercaptoethanol-stimulated cellulases I and II. The tolerance to cellulose hydrolysis products and the high thermal stabilities of Scytalidium cellulases suggest good potential for industrial applications. 相似文献
992.
C. J. H. Souza A. S. McNeilly M. V. Benavides E. O. Melo J. C. F. Moraes 《Animal genetics》2014,45(5):732-739
Litter size (LS) in sheep is determined mainly by ovulation rate (OR). Several polymorphisms have been identified in the growth differentiation factor 9 (GDF9) gene that result in an increase in OR and prolificacy of sheep. Screening the databank of the Brazilian Sheep Breeders Association for triplet delivery, we identified flocks of prolific Ile de France ewes. After resequencing of GDF9, a point mutation (c.943C>T) was identified, resulting in a non‐conservative amino acid change (p.Arg315Cys) in the cleavage site of the propeptide. This new allele was called Vacaria (FecGv). A flock of half‐sib ewes was evaluated for OR in the first three breeding seasons, and Vacaria heterozygotes had higher OR (P < 0.001), averaging 2.1 ± 0.1 when compared to 1.2 ± 0.1 in wild‐type ewes. The OR was also influenced by age, increasing in the second and third breeding seasons (P < 0.001). In flocks segregating this allele, the LS was higher in mutant sheep (P < 0.001), averaging 1.61 ± 0.07 in heterozygotes and 1.29 ± 0.03 in wild‐type ewes. Analysis of homozygote reproductive tract morphology revealed uterine and ovarian hypoplasia. Ovarian follicles continue to develop up to small antral stages, although with abnormal oocyte morphology and altered arrangement of granulosa cells. After the collapse of the oocyte in most follicles, the remaining cells formed clusters that persisted in the ovary. This SNP is useful to improve selection for dam prolificacy and also as a model to investigate GDF9 post‐translation processing and the fate of the follicular cells that remain after the oocyte demise. 相似文献
993.
994.
Nadia Melo Matthew Capek Oscar M. Arenas Ali Afify Ayse Yilmaz Christopher J. Potter Peter J. Laminette Alessia Para Marco Gallio Marcus C. Stensmyr 《Current biology : CB》2021,31(9):1988-1994.e5
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995.
Carla S. Alves Manuel N. Melo Henri G. Franquelim Rafael Ferre Marta Planas Lidia Feliu Eduard Bardají Wioleta Kowalczyk David Andreu Nuno C. Santos Miguel X. Fernandes Miguel A. R. B. Castanho 《The Journal of biological chemistry》2010,285(36):27536-27544
The potential of antimicrobial peptides (AMPs) as an alternative to conventional therapies is well recognized. Insights into the biological and biophysical properties of AMPs are thus key to understanding their mode of action. In this study, the mechanisms adopted by two AMPs in disrupting the Gram-negative Escherichia coli bacterial envelope were explored. BP100 is a short cecropin A-melittin hybrid peptide known to inhibit the growth of phytopathogenic Gram-negative bacteria. pepR, on the other hand, is a novel AMP derived from the dengue virus capsid protein. Both BP100 and pepR were found to inhibit the growth of E. coli at micromolar concentrations. Zeta potential measurements of E. coli incubated with increasing peptide concentrations allowed for the establishment of a correlation between the minimal inhibitory concentration (MIC) of each AMP and membrane surface charge neutralization. While a neutralization-mediated killing mechanism adopted by either AMP is not necessarily implied, the hypothesis that surface neutralization occurs close to MIC values was confirmed. Atomic force microscopy (AFM) was then employed to visualize the structural effect of the interaction of each AMP with the E. coli cell envelope. At their MICs, BP100 and pepR progressively destroyed the bacterial envelope, with extensive damage already occurring 2 h after peptide addition to the bacteria. A similar effect was observed for each AMP in the concentration-dependent studies. At peptide concentrations below MIC values, only minor disruptions of the bacterial surface occurred. 相似文献
996.
997.
Cleiton A. Domingos José W. Da S. Melo Manoel G. C. GondimJr. Gilberto J. De Moraes Rachid Hanna Late M. Lawson-Balagbo Peter Schausberger 《Experimental & applied acarology》2010,50(3):201-215
Neoseiulus baraki Athias-Henriot (Acari: Phytoseiidae) has been reported from the Americas, Africa and Asia, often in association with Aceria guerreronis Keifer (Acari: Eriophyidae), one of the most important pests of coconut (Cocos nucifera L.) in different parts of the world. That phytoseiid has been considered one of the most common predators associated with
A. guerreronis in Brazil. The objective of this study was to evaluate the feeding preference and the effect of food items commonly present
on coconut fruits and several temperature regimes on the life history of a Brazilian population of N. baraki. Completion of immature development was possible when N. baraki was fed A. guerreronis, Steneotarsonemus concavuscutum Lofego and Gondim Jr., and Tyrophagus putrescentiae (Schrank). Fecundity was highest on T. putrescentiae (39.4 eggs), followed by A. guerreronis (24.8 eggs). In choice tests, irrespective of the food on which N. baraki was reared, a larger number of adults of this predator chose leaf discs containing A. guerreronis than discs containing other food items, demonstrating a preference of the former for the latter as food. Egg to adult thermal
developmental time was calculated as 84.2 degree-days, above a threshold of 15.8°C. This lower developmental threshold is
higher than previously published for phytoseiid species from higher latitudes. Neoseiulus
baraki was shown to have higher biotic potential at 30°C (r
m 0.29). The results suggest N. baraki to be a promising biological control agent of A. guerreronis, well adapted to survive and develop in areas with relatively high temperatures, where that pest prevails. 相似文献
998.
Wilson Marcelo da Silva Júnior Fabiano Rodrigues de Melo Leandro Santana Moreira Elaine Ferreira Barbosa João Augusto Alves Meira-Neto 《Ecological Research》2010,25(1):25-32
This work examines patches of Atlantic forests in Minas Gerais State where woolly spider monkeys (Brachyteles
hypoxanthus) are inhabitants in order to understand the effects of forest structure, diversity, and succession in B.
hypoxanthus abundance. This study was carried out in three reserves: Rio Doce State Park (PERD), Mata do Sossego (Sossego), and Serra
do Brigadeiro State Park (PESB). Structural studies were carried out by means of point-centered quarter samples in areas used
by woolly spider monkeys. Evenness was lower in PERD than in the other two communities. By means of successional functional
groups analysis and diametric structure, the PERD forest sample was shown to be in the later, and PESB forest sample in the
earlier, stages of secondary succession. We found that tree species evenness and structural traits driven by succession were
important factors in determining spider monkey abundance patterns. The PERD forest sample had lower evenness and had lower
density of woolly spider monkeys than the Sossego forest sample. The lowest density of these primates was in the PESB forest
sample, the earlier successional stage of secondary succession of this study. 相似文献
999.
Siqueira RS Bonjardim LR Araújo AA Araújo BE Melo MG Oliveira MG Gelain DP Silva FA DeSantana JM Albuquerque-Júnior RL Rocha RF Moreira JC Antoniolli AR Quintans-Júnior LJ 《Zeitschrift für Naturforschung. C, Journal of biosciences》2010,65(9-10):551-561
Physicochemical characterization and antinociceptive and anti-inflammatory activities of atranorin (AT) extracted from Cladina kalbii Ahti in formalin- and capsaicin-induced orofacial pain and anti-inflammatory tests in rodents were studied. Physicochemical characterization showed that AT has the general formula C19H18O8. Male Swiss mice were pretreated with AT (100, 200, and 400 mg/kg, i.p.), morphine (3 mg/kg, i.p.), or vehicle (0.9% saline with two drops of 0.2% Tween 80) before formalin (20 microl, 2%) or capsaicin (20 microl, 2.5 microg) were injected into the right vibrissa. Our results showed that i.p. treatment with AT displayed marked inhibitory effects in different orofacial pain tests in mice. AT (400 mg/kg, i.p.) was effective in reducing the nociceptive face-rubbing behavioural response in both phases of the formalin test, which was also naloxone-sensitive. Additionally, AT produced a significant antinociceptive effect at all doses in the capsaicin test. Such results were unlikely to be provoked by motor abnormality, since AT-treated mice exhibited no performance alteration on the rota rod apparatus. AT exhibited significant anti-inflammatory activity in the acute model of inflammation (leukocyte migration to the peritoneal cavity), carrageenan- and arachidonic acid-induced hind paw edema in rats. Additionally, AT exhibited a dose-dependent antioxidant activity in vitro, as assessed by total radical-trapping antioxidant parameter and total antioxidant reactivity assays. All these findings suggest that AT might represent an important tool for the management of orofacial pain and/or inflammatory disorders. 相似文献
1000.
Fernando Faria Franco Erica Cristina Carvalho Silva‐Bernardi Fabio Melo Sene Esteban Ruben Hasson Maura Helena Manfrin 《Journal of Zoological Systematics and Evolutionary Research》2010,48(4):322-331
We have measured nucleotide variation in the CLOCK/CYCLE heterodimer inhibition domain (CCID) of the clock X‐linked gene period in seven species belonging to the Drosophila buzzatii cluster, namely D. buzzatii, Drosophila koepferae, Drosophila antonietae, Drosophila serido, Drosophila gouveai, Drosophila seriema and Drosophila borborema. We detected that the purifying selection is the main force driving the sequence evolution in period, in agreement with the important role of CCID in clock machinery. Our survey revealed that period provides valuable phylogenetic information that allowed to resolve phylogenetic relationships among D. gouveai, D. borborema and D. seriema, which composed a polytomic clade in preliminary studies. The analysis of patterns of intraspecific variation revealed two different lineages of period in D. koepferae, probably reflecting introgressive hybridization from D. buzzatii, in concordance with previous molecular data. 相似文献