Lysosomal permeability to potassium ions is an important property of the organelle. Influence of the membrane physical state on the potassium ion permeability of isolated lysosomes was assessed by measuring the membrane potential with bis(3-propyl-5-oxoisoxazol-4-yl)pentamethine oxonol and monitoring the lysosomal proton leakage with p-nitrophenol. The membrane fluidity of lysosomes was modulat...

The steroidal diamine irehdiamine A (IDA) is a potent inhibitor of bacteriophage growth and macromolecular synthesis in Escherichia coli. By using radioactive (42)K and (14)C-thiomethylgalactoside (TMG), rapid effects of IDA and related steroids, both on the influx of potassium and TMG via their respective transport systems and on the efflux (leakage) of radioactivity from the treated cells, ha...

During storage, erythrocytes undergo changes that alter their clearance and function after transfusion and there is increasing evidence that these changes contribute to the complications observed in transfused patients. Stored erythrocytes were incubated overnight at 37°C to mimic the temperature after transfusion. After incubation, several markers for erythrocyte damage were analysed. After ov...

In order to investigate the responses of potato plantlets under in vitro conditions to osmotic and temperature stresses, a factorial experiment was carried out in a completely randomized design with three replications. Each replicate contained a glass jar with 5 explants grown in it. The first...

We studied the toxic effects of amphotericin B and gramicidin S, alone and in combination, using free and liposome-encapsulated drugs. In vitro toxic effects of the drugs on human erythrocytes and Candida albicans were determined by measuring leakage of intracellular potassium ions (K+). Liposomal formulations of both drugs greatly reduced K+ leakage from human erythrocytes, whereas liposomal g...

With increasing frequency and intensity of dry spells in the cocoa production zones West Africa, strategies for mitigating impact water stress on seedling survival are urgently required. We investigated effects applied potassium biomass accumulation, physiological processes varieties subjected to pot experiments a gauzehouse facility. Four levels (0, 1, 2, or 3 g/plant as muriate potash) were u...

Cellular leakage observed in Escherichia coli K-12-M shortly after T7 infection might be the cause of arrested phage morphogenesis. We observed in this strain, but not in the normal host, a drastic reduction of the intracellular concentration of potassium (60%), magnesium (40%), putrescine (90%), and spermidine (40%), whereas ATP was not significantly reduced. Leakage started about 1 min after ...

2,4,6-Trinitro-3-methyl-phenol (trinitrocresol, H(+)TNC(-)) was found to inhibit anion and stimulate cation movements across the membranes of both high potassium (HK) and low potassium (LK) sheep red blood cells. The concentration of TNC(-) required to inhibit SO(4) (-) and Cl(-) efflux (10(-5)-10(-3)M) was less than that required to increase Na(+) and K(+) leakage (10(-3)-10(-2)M). Both the in...

The ability of glycinecin A, a bacteriocin derived from Xanthomonas campestris pv. glycines 8ra, to kill closely related bacteria has been demonstrated previously by our group. In the present study, we aimed at determining the glycinecin A-induced cause of death. Treatment with glycinecin A caused slow dissipation of membrane potential and rapid depletion of the pH gradient. Glycinecin A treatm...