Search results for "RME"

Influence of autochthonous microbiota on the sicilian wine producution

2014

Divalent Cations Reduce the pH Sensitivity of OmpF Channel Inducing the PKA Shift of Key Acidic Residues

2011

In contrast to the highly-selective channels of neurophysiology employing mostly the exclusion mechanism, different factors account for the selectivity of large channels. Elucidation of these factors is essential for understanding the permeation mechanisms in ion channels and their regulation in vivo. The interaction between divalent cations and a protein channel, the bacterial porin OmpF, has been investigated paying attention to the channel selectivity and its dependence on the solution pH. Unlike the experiments performed in salts of monovalent cations, the channel is now practically insensitive to pH, being anion selective all over the pH range considered. Electrostatic calculations bas…

Recensione a Il carme 67 di Catullo. Introduzione, edizione critica, traduzione e commento a cura di ORAZIO PORTUESE, Cesena, Stilgraf, 2013 (Quadern…

2015

Reviewed Work - Il carme 67 di Catullo, (Quaderni di «Paideia») by Orazio Portuese, Cesena 2013, pp. 420, ISBN 978-88-96240-39-7 Recensione a "Il carme 67 di Catullo", (Quaderni di «Paideia») a cura di Orazio Portuese, Cesena 2013, pp. 420, ISBN 978-88-96240-39-7

La ‘tragedia’ del carme 64

2011

Bacillus thuringiensis Cry1Ac Toxin-Binding and Pore-Forming Activity in Brush Border Membrane Vesicles Prepared from Anterior and Posterior Midgut R…

2008

ABSTRACT It is generally accepted that Bacillus thuringiensis Cry toxins insert into the apical membrane of the larval midgut after binding to specific receptors, and there is evidence that the distribution of binding molecules along the midgut is not uniform. By use of the voltage-sensitive dye DiSC 3 (5) and 125 I-labeled Cry1Ac, we have measured the effect of Cry1Ac in terms of permeabilization capacity and of binding parameters on brush border membrane vesicles (BBMV) prepared from the anterior and the posterior regions of the larval midgut from two insect species, Manduca sexta and Helicoverpa armigera . The permeabilizing activity was significantly higher with BBMV from the posterior …

Staphylococcal alpha-toxin: repair of a calcium-impermeable pore in the target cell membrane

2000

Staphylococcal alpha-toxin forms heptameric pores that render membranes permeable for monovalent cations. The pore is formed by an amphipathic beta-barrel encompassing amino acid residues 118-140 of each subunit of the oligomer. Human fibroblasts are susceptible to alpha-toxin but are able to repair the membrane lesions. Thereby, toxin oligomers remain embedded in the plasma membrane and exposed to the extracellular medium. In this study, we sought to detect structural changes occurring in the pore-forming sequence during lesion repair. Single cysteine substitution mutants were labelled with the environmentally sensitive fluorochrome acrylodan and, after mixing with wild-type toxin, incorpo…

Cryopreservation of Escherichia coli K12TG1: Protection from the damaging effects of supercooling by freezing

2015

Injuries in living cells caused by water freezing during a freeze-thaw process have been extensively reported. In particular, intracellular water freezing has long been incriminated in cell death caused by a high cooling rate, but this supposition could not always be demonstrated. This work aims to discriminate the role of water freezing, dehydration and cold-induced injuries in cellular damage occuring during cryopreservation. For this purpose, Escherichia coli K12TG1 suspensions were maintained in a supercooled or frozen state at -20°C for times ranging from 10 min to 5 h. The supercooled state was maintained for a long period at -20°C by applying a non-injurious isostatic pressure (P<40 …

Permeabilization of the erythrocyte membrane with streptolysin O allows access to the vacuolar membrane of Plasmodium falciparum and a molecular anal…

1997

Selective permeabilization of infected host cells with pore-forming proteins provides a novel tool to study protein synthesis and viability of the in…

2001

Protein sorting in Plasmodium falciparum-infected red blood cells permeabilized with the pore-forming protein streptolysin O

1996

Plasmodium falciparum is an intracellular parasite of human red blood cells (RBCs). Like many other intracellular parasites, P. falciparum resides and develops within a parasitophorous vacuole which is bound by a membrane that separates the host cell cytoplasm from the parasite surface. Some parasite proteins are secreted into the vacuolar space and others are secreted, by an as yet poorly defined pathway, into the RBC cytosol. The transport of proteins from the parasite has been followed mainly using morphological methods. In search of an experimental system that would allow (i) dissection of the individual steps involved in transport from the parasite surface into the RBC cytosol, and (ii…