ATP-dependent K+ uptake by a photosynthetic purple sulfur bacterium
Davidson, V.L.; Knaff, D.B.
Archives of Biochemistry and Biophysics 213(2): 358-362
ISSN/ISBN: 0003-9861 PMID: 7073281 DOI: 10.1016/0003-9861(82)90561-6
Chromatium vinosum contains an ATP-dependent K+ uptake system which is light independent and sensitive to DCCD [N,N'-dicyclohexylcarbodiimide]. Kinetic measurements show Km = 0.27 mM for K+ and Km = 1.3 mM for Tl+, an alernate substrate. The internal K+ content of the cell increases with increasing medium osmolality and is unaffected by changes in external K+ concentration.