摘要
In plant cells, the accumulation of K^+ plays a primary role in osmotic regulation,and high-affinity K^+ uptake and transport systems have been investigated. InEscherichia coli, Hesse et aI.isolated a specific K^+ uptake system known as Kdpwhich has a K_m of 2 μmol/L, and it was induced by osmotic stress. Its kdpABCgenes encode three membrane-binding proteins whose molecular weights are 47, 90 and22 kD, respectively, and kdpDE genes produce two regulatory factors. Gaber et al.
