PubMed · 5154974
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
R T Smith. Membrane alterations in red cell injuries.. https://pubmed.ncbi.nlm.nih.gov/5154974/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Yeasts are beneficial microorganisms for human society and are utilized for academic and industrial purposes. For academic purposes, S. cerevisiae is a well-investigated model for studying eukaryotic cellular processes. For industrial purposes, S. pastorianus, which has a hybrid genome of S. cerevisiae and S. eubayanus, has been served for lager beer production. During fermentation, S. pastorianus produces ~7% of EtOH, which induces plasma membrane (PM)/cell wall stress in yeast. Therefore, S. pastorianus may experience PM stress and adapt to the self-forming environment during fermentation. However, how yeast adapts to PM stress remains unclear. Here, we investigated the temporal cellular responses of S. cerevisiae and S. pastorianus during adaptation to PM stresses by time-resolved mRNA-seq analysis. Our data showed different transcriptional phenotypes between S. cerevisiae and S. pastorianus during adaptation. The results may reflect the distinct nature of the two yeasts that have evolved in different nutritional environments. The dataset presented here would provide a promising resource for studying the characteristic nature of these differentially domesticated yeasts upon PM stresses.
The anion-selective porin Omp34 from Acidovorax delafieldii was unidirectionally reconstituted in planar lipid membranes. Pore closing was recorded particularly at low salt conditions for negative and positive membrane potentials in the range of +/-10 to +/-100 mV. Relaxation curves were fitted by exponential functions in order to describe and to analyze the voltage-dependent behavior. Omp34 exhibited the following characteristics: (i) The channels are asymmetric with respect to closing characteristics and corresponding functional parameters. (ii) Relaxation curves can be fitted by a single exponential function in the low voltage range only, at >/=40 mV combinations of two exponential functions are required. (iii) Beyond 60 to 70 mV a third exponential function is necessary to fit the fast closing components properly. The time constants differ by two to three orders of magnitude. (iv) Hysteresis in I-V-diagrams originate from slow relaxation components which are different for positive and negative voltages. The implications for models aiming at description of voltage-dependent closing are discussed.
A technique is described that allows the application of fast temperature changes (time constant approximately 300 ms) of solutions superfusing cultured neurones under whole-cell mode of membrane current recording. Its principle is in heating the common outlet of the manifold which consists of 12 tubes connected to barrels containing test solutions of different composition. The outlet is made from a glass capillary (25 mm length, 620/350 microns outer/inner diameter) coated on the outside wall with platinum for a length of 12 mm. The heating element, a platinum layer, is electrically connected to the probe fixed to the micromanipulator used for positioning the manifold. The solutions, driven by gravity, are applied by opening electronic valves controlled either manually or in programmed sequences. The DC current for heating is controlled either manually or by external voltage command. The advantage of the technique is that the same temperature pattern can be applied to 12 different solutions. The technique is used for classifying sensory neurones in culture with respect to their sensitivity to heat and algogens; however, it is applicable to any study of the effects of increased temperature on the activity of ion channels in cultured cells.