抄録
Washed cells of Staphylococcus aureus FDA 209P accumulated thiamine (B_1) in the presence of glucose and high concentration of buffer (more than 0.1 M) at 37℃. The process of accumulation was clearly distinguished from the adsorption of B_1 by (1) heat instability, (2) optimum pH (8.2 or more alkaline), (3) accumulation of B_1 phosphates, (4) accumulation in the presence of high ionic strength, (5) optimum temperature (42℃ for the initial rate), and (6) Km (1.3×10^<-6>M). The uptake activity was repressed by high concentration of B_1 in the growth medium. Pyrithiamine competed the uptake of free B_1 and free B_1 competed the accumulation of pyrithiamine. Pyrithiamine was taken up and phosphorylated in the cell. TDP was also taken up by the cell and accumulated as B_1 phosphates, which could not be accounted for by the mechanisms posturating the hydrolysis of TDP to free B_1 prior to the penetration into bacterial membrane, followed by phosphorylation of free B_1 in the cell.
