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111.
112.
Guadalupe Medina-de la Rosa Moisés Graciano Carcaño-Montiel Jesús Francisco López-Olguín Miguel Ángel Hernández-Espinosa José Antonio Rivera-Tapia 《Archives Of Phytopathology And Plant Protection》2016,49(11-12):310-321
The chitinase enzyme was identified in isolated bacteria of maize rhizosphere as well as its potential for the biological control of fungi associated at seeds of the same plant. The production of chitinase enzyme was found in the genera identified as Acinetobacter, Bacterium, Burkholderia, Paenibacillus, Pseudomonas, Rhizobium, Shewanella, Sphingomonas and Stenotrophomonas. Bacterial isolates with ability to degrade fungal mycelium from maize fungi as Fusarium and Alternaria among others, were detected. Bacterial chitinase activity and the presence of the chiA gene were determined. The inoculation of chitinolytic bacteria showed a positive effect in the control of fungi in maize seeds. The results support the potential use of chitinase enzyme producing bacteria on the control of phytopathogenic fungi. 相似文献
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Ernesto E. Ambroggio Guadalupe S. Costa Navarro Luis Benito Prez Socas Luis A. Bagatolli Andrea V. Gamarnik 《The Journal of biological chemistry》2021,297(3)
Dengue virus (DENV) and Zika virus (ZIKV) capsid proteins efficiently recruit and surround the viral RNA at the endoplasmic reticulum (ER) membrane to yield nascent viral particles. However, little is known either about the molecular mechanisms by which multiple copies of capsid proteins assemble into nucleocapsids (NCs) or how the NC is recruited and wrapped by the ER membrane during particle morphogenesis. Here, we measured relevant interactions concerning this viral process using purified DENV and ZIKV capsid proteins, membranes mimicking the ER lipid composition, and nucleic acids in in vitro conditions to understand the biophysical properties of the RNA genome encapsidation process. We found that both ZIKV and DENV capsid proteins bound to liposomes at liquid-disordered phase regions, docked exogenous membranes, and RNA molecules. Liquid–liquid phase separation is prone to occur when positively charged proteins interact with nucleic acids, which is indeed the case for the studied capsids. We characterized these liquid condensates by measuring nucleic acid partition constants and the extent of water dipolar relaxation, observing a cooperative process for the formation of the new phase that involves a distinct water organization. Our data support a new model in which capsid–RNA complexes directly bind the ER membrane, seeding the process of RNA recruitment for viral particle assembly. These results contribute to our understanding of the viral NC formation as a stable liquid–liquid phase transition, which could be relevant for dengue and Zika gemmation, opening new avenues for antiviral intervention. 相似文献
116.
The Pacific jack Caranx caninus is a common species fished by artisanal fishermen off the coast of Colima, México. During 2002, monthly samples of morphometric data and otoliths were taken to determine age and growth. Seven age groups were identified. The highest growth, 14.4 cm, takes place during the first year of life. During the second year, C caninus grows 11.76 cm; the third year 9.61 cm; the fourth 7.85 cm; the fifth 6.41 cm and sixth year 5.24 cm. The constants of von Bertalanffy's growth equation were: L(infinity) = 83.26 cm, W(infinity) = 18.138 g, K = 0.202, t(0) = -0.283 and A(0.95) = 15 years. Growth curves of other species of the same genus were calculated in order to compare them with the one obtained in the present work. The gonadosomatic index presented higher values during November and May. The periods of more intensive feeding are from August to February. 相似文献
117.
In vitro effect of malathion and diazinon on oocytes fertilization and embryo development in porcine
Yvonne Ducolomb Eduardo Casas Alejandra Valdez Guadalupe González Mario Altamirano-Lozano Miguel Betancourt 《Cell biology and toxicology》2009,25(6):623-633
Diazinon and malathion are commonly used organophosphate insecticides in agriculture, industry, and in veterinary medicine
as an ectoparasiticide. The importance to carry out in vitro reproductive toxicology assays lies on the need of knowing the
alterations these insecticides may cause at cellular level, since they are endocrine disruptors that interfere with reproductive
functions. The aim of this study was to evaluate in vitro oocyte viability, fertilization, and embryo development with different
concentrations of diazinon and malathion. For in vitro fertilization (IVF), porcine oocytes and sperm were co-incubated for
7 h with increasing concentrations (50, 100, and 500 μM) of diazinon and malathion. For embryo development, fertilized oocytes
were cultured in medium containing the same insecticide concentrations during 96 h for embryo development and 144 h for morulae
formation. Diazinon did not affect oocyte viability and embryo divisions but decreased IVF (fertilization inhibition50 = 502 μM) and morulae formation (morulae inhibition50 = 344 μM). Malathion affected all the studied parameters: lethal concentration50 = 1 mM, fertilization inhibition50 = 443 μM, development inhibition50 = 375 μM, and morulae inhibition50 = 216 μM. The results of this study indicate that diazinon and malathion used in commercial formulation could be toxic, producing
impairment in in vitro fertilization and embryo development. This is an approach for further investigations to find out cell
damage mechanisms produced by these widely used insecticides. 相似文献
118.
Marín-Martinez R Veloz-García R Veloz-Rodríguez R Guzmán-Maldonado SH Loarca-Pina G Cardador-Martinez A Guevara-Olvera L Miranda-López R Torres-Pacheco I Pérez CP Herrera-Hernández G Villaseñor-Ortega F González-Chavira M Guevara-Gonzalez RG 《Bioresource technology》2009,100(1):434-439
Quebracho extracts are used in tannery due to their high concentration of phenolics. The Mexican tannery industry uses around 450 kg/m(3) of which, 150 kg/m(3) remains in wastewaters and are discharged in drain pipe systems or rivers. The quebracho phenolics recovered from tannery wastewater (QPTW) was characterized by HPLC. The antimutagenic and antioxidant activities as well as the microbiological quality were evaluated. Total phenolic content of QPTW was 621mg catechin equivalent/g sample. Gallic and protocatechuic acids were the major components characterized by HPLC. QPTW showed an inhibition range on aflatoxin B(1) mutagenicity from 16 to 60% and was dose-dependent. Antioxidant activity (defined as beta-carotene bleaching) of QPTW (64.4%) at a dose of 12.3mg/mL was similar to that of BHT (68.7%) at a dose of 0.33 mg/mL, but lower than Trolox (90.8% at a dose of 2.5mg/mL); meanwhile antiradical activity (measured as reduction of DPPH) (60.8%) was higher than that of BHT (50.8%) and Trolox (34.2%). Quebracho residues were demonstrated to be an outstanding source of phenolic acids and for research and industrial uses. 相似文献
119.
Maria Guadalupe Vizoso Pinto Josefina Maria Villegas Jan Peter Rudolf Haase Jürgen Haas Amelie Sophia Lotz Ania Carolina Muntau Armin Baiker 《Proteomics》2009,9(23):5303-5308
The GC content is highly variable among the genomes of different organisms. It has been shown that recombinant gene expression in mammalian cells is much more efficient when GC‐rich coding sequences of a certain protein are used. In order to study protein–protein interactions in Varicella zoster virus, a GC‐low herpesvirus, we have developed a novel luminescence‐based maltose‐binding protein pull‐down interaction screening system (LuMPIS) that is able to overcome the impaired protein expression levels of GC‐low ORFs in mammalian expression systems. 相似文献
120.
Raimon Sanmartí Eduard Graell Maria L Perez Guadalupe Ercilla Odette Vi?as Jose A Gómez-Puerta Jordi Gratacós Alejandro Balsa Maria J Gómara Marta Larrosa Juan D Ca?ete Isabel Haro 《Arthritis research & therapy》2009,11(5):R135