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11.
Cloning and molecular characterization of two genes encoding adhesion proteins involved in Trichomonas vaginalis cytoadherence 总被引:11,自引:2,他引:9
12.
Washed chloroplast membranes from romaine lettuce leaves were treated with the cross-linking reagent dimethyladipimidate (DMA) for various periods of time and subsequently analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Comparative examination of the electrophoretic profiles from control and treated membranes revealed that the light-harvesting chlorophyll-protein complex (LHCPC) was readily cross-linked to yield “dimers” and “oligomers” of higher molecular weight. Two polypeptides, of 25 and 23 kilodaltons, previously identified as two subunits of the LHCPC, were the major cross-linked species; other peptides were also cross-linked, but to a much lesser extent. These results suggest that cross-linking of chloroplast membranes with DMA, under our conditions, occurs primarily among the components of the LHCPC. We also measured the photosystem II activity in control and DMA-treated chloroplasts and found no impairment of this photochemical activity in the cross-linked chloroplasts as compared with controls. 相似文献
13.
E J Van Zoelen C Henriques de Jesus E de Jonge M Mulder M C Blok J de Gier 《Biochimica et biophysica acta》1978,511(3):335-347
1. The reflection coefficient for the permeation of thiourea through bilayers of phosphatidylcholine is a function of the fatty-acid composition of the lipid molecules. By means of these reflection coefficients an index for membrane fluidity has been given to each of those lipids, relative to that of egg phosphatidylcholine. 2. The maximum number of water molecules that can copermeate with each molecule of solute by means of solute-solvent interaction is a function of the packing of the lipid molecules in the bilayer. This parameter has been used in this paper for characterizing the fluidity of cholesterol-containing membranes and for membranes with their lipids in the gel state. 相似文献
14.
In the present study we extend previous work from this laboratory on the polypeptide composition of photosynthetic lamellae. Using a high resolution sodium dodecyl sulfate gel electrophoresis technique, we show that both grana and stroma lamellae have qualitatively very similar polypeptide compositions although some clear quantitative differences are demonstrated. 相似文献
15.
16.
Signalling of Trichomonas vaginalis for amoeboid transformation and adhesin synthesis follows cytoadherence 总被引:2,自引:0,他引:2
Rossana Arroyo Arturo González-Robles Adolfo Martínez-Palomo J. F. Alderete 《Molecular microbiology》1993,7(2):299-309
The cytoadherence of Trichomonas vaginalis, the sexually transmitted flagellated protozoan, to vaginal epithelial cells (VECs) is the key to infection. Electron microscopy revealed that in vitro-grown parasites having typical globular shape transformed rapidly after contact with VECs into thin, flat, amoeboid cells, maximizing the area of adhesion to the surface of VECs. Amoebic trichomonads formed filopodia and pseudopodia, which interdigitated at distinct sites on the plasma membrane of target cells. In contrast, the amoeboid transformation did not occur for T. vaginalis interacting with He La cells, the previously used in vitro host model cell. Initial parasitism of VECs by a single organism was followed by establishment of a monolayer of trichomonads on the host cell. Finally, parasites adhering to either VECs or HeLa cells were induced to synthesize greater amounts of the four previously described adhesins. Therefore, distinct signals after contact with either epithelial cell type leads to the morphological transformation and/or induction of adhesin synthesis by T. vaginalis. 相似文献
17.
Marking of sited cells after electrophysiologic study 总被引:1,自引:0,他引:1
18.
Rossana Saracino Chiara Capponi Sara Di Persio Carla Boitani Silvia Masciarelli Francesco Fazi Stefania Fera Elena Vicini 《Molecular reproduction and development》2020,87(4):419-429
Glial cell line‐derived neurotrophic factor (GDNF) and retinoic acid (RA) are two molecules crucial for the regulation of the spermatogonial compartment of the testis. During the cycle of the seminiferous epithelium, their relative concentration oscillates with lower GDNF levels in stages where RA levels are high. It has been recently shown that RA negatively regulates Gdnf expression but the mechanisms behind are so far unknown. Here, we show that RA directly downregulates Gdnf mRNA levels in primary murine Sertoli cells through binding of RARα to a novel DR5‐RARE on Gdnf promoter. Pharmacological inhibition and chromatin immunoprecipitation–quantitative polymerase chain reaction analysis suggested that the underlying mechanism involved histone deacetylase activity and epigenetic repression of Gdnf promoter upon RA treatment. 相似文献
19.
Basso Rossana Patricia Poester Vanice Rodrigues Benelli Jéssica Louise Stevens David A. Zogbi Heruza Einsfeld Vasconcellos Izadora Clezar da S. Pasqualotto Alessandro Comarú Xavier Melissa Orzechowski 《Mycopathologia》2021,186(1):109-112
Mycopathologia - Most reports associating fungal infections with COVID-19 have been cases of invasive aspergillosis. Here, we report a case of severe histoplasmosis and COVID-19 infections in an... 相似文献
20.
Câmara Paulo E. A. S. Convey Peter Rangel Sandro B. Konrath Marcelo Barreto Cristine Chaves Pinto Otavio H. B. Silva Micheline Carvalho Henriques Diego Knop de Oliveira Hermeson Cassiano Rosa Luiz H. 《Extremophiles : life under extreme conditions》2021,25(4):369-384
Extremophiles - As part of the reconstruction of the Brazilian Antarctic Station on King George Island, three areas of moss carpet were transplanted to minimize the impact of the new facilities on... 相似文献