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J Slavík

Publications and source records attributed to J Slavík.

35 records · Page 2Linked to original sources
PubMed1983

Intracellular pH topography: determination by a fluorescent probe.

The distribution of pH inside the yeast Endomyces magnusii was measured at 1 micron resolution using different external pH values. In a neutral buffer the pH of the cytoplasm was 6.7-7.2 in the center, decreasing to 6.0 toward the periphery of the cell. A decrease of external pH was followed by a gradual uniform decrease of internal pH. Using a comparison of the 'pH map' with phase-contrast picture of the same cell, the pH of the vacuoles was estimated to be 5.5-5.6.

Cells↗
PubMed1982

Anilinonaphthalene sulfonate fluorescence and amino acid transport in yeast.

Fluorescence of 1-anilinonaphthalene-8-sulfonate in yeast membranes appears to be caused predominantly by binding to lipids (ANS protein:ANS lipid approximately 1 : 20) as indicated by the fluorescence lifetime, degree of polarization, and excitation spectra. It was insensitive to short-circuiting the membrane potential. Fluorescence intensity increased as cells (especially after pretreatment with energy donors such as glucose) were exposed to some amono acids, in particular, aspartic and glutamic acids. The character of fluorescence shifted to that of protein-bound ANS, suggesting an exposure of new protein sites accessible to the probe. This shift could be prevented by inhibitors of energy transduction as well as of transport. The K1/2 of the shift was at 2.5 mM aspartic acid.

Amino Acids↗