The Effect of Ultraviolet Light on the Sodium and Potassium Composition of Resting Yeast Cells
نویسندگان
چکیده
The Na(+) and K(+) content of non-metabolizing yeast cells was determined before and after monochromatic ultraviolet (UV) irradiation. UV facilitated the uptake of Na(+) into and the loss of K(+) from the cells (net ion flux); the effect is greatest for the shortest wavelength employed (239 mmicro) and is partly dependent upon the presence of oxygen. The UV effect on net ion flux persists for at least 90 minutes during which tests were made and it occurs following dosages which are without measurable effect on colony formation. The UV effect on net ion flux is decreased by acidity and promoted by alkalinity. Addition of calcium ions in sufficient amount prevents the usual net ion flux changes observed in irradiated yeast. Increase in concentration gradient between the inside and the outside of the cell increases the net ion flux of irradiated yeast, Na(+) uptake leading K(+) loss in all cases. UV appears to act by disorganizing the constituents of the cell surface, permitting K(+) to leave the cell in exchange for Na(+). At low intensities of UV this ionic exchange approaches equivalence, but at higher intensities more Na(+) is taken up than K(+) is lost. Some evidence suggests that the Na(+) in excess over that exchanged for K(+) is adsorbed to charged groups produced by the photochemical effect of UV on the cell surface.
منابع مشابه
Effect of Berberis vulgaris Aqueous Extract on the Apoptosis, Sodium and Potassium in Hepatocarcinogenic Rats
Objective(s) The effect of Berberis vulgaris aqueous extract in hepatocarcinogenic rats was studied to investigate the apoptotic and sodium, potassium elements properties. A loss of both intracellular potassium and sodiumoccurs when apoptotic cells shrink and prior to the loss of membraneintegrity. Materials and Methods Forty-eight Sprague dawley rats were randomly divided into 2 groups, normal...
متن کاملChemical Composition, Yield and Yield Components of Two Wheat Cultivars in Response to Salt Stress
Abstract In most southern provinces of Iran, soil salinity is a growing problem, particularly in irrigated agricultural areas, and has been found to reduce wheat yield, dramatically. To investigate the effect of sodium chloride on two wheat (Triticum aestivum L.) cultivars, four levels of salinity: 0, 4, 8 and 12 dS/m, were employed as a factorial experiment arranged in a randomized complet...
متن کاملThe mechanism of action of methanolic extract of Rumex alveolatus on the membranes of Candida albicans, Candida paraposilosis and Candida glabratata
Background: Candidiasis is a common fungal disease that is caused by different species of genital herpes and involves various parts of the body. These infections can be fatal in light of the host's immune status. Following the advancement of science and the importance of the health sector in societies, the use of chemical drugs has increased. However, due to side effects, high prices and the co...
متن کاملThe effect of incoherent ultraviolet light on the renal capsule tissue using dynamic mechanical analysis and FTIR spectroscopy
متن کامل
Effect of composition electrolyte on the morphology and photocatalytic activity of anodized titanium nanoporous
The morphology of titanium dioxide and titanium dioxide-tungsten trioxide nanocomposite films fabricated by anodizing in a glycerol solution containing 0.13 M NH4F and different quantity of Na2WO4 was investigated as a function of sodium tungstate concentrations. The effects of sodium tungstate concentration on the surface morphology were observed by scanning electron microscopy (SEM). It was c...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Journal of General Physiology
دوره 42 شماره
صفحات -
تاریخ انتشار 1959