However, RF permease did not delivery glucose, because it inhibited RF permease with unchanged effectivity in python mutant that was completely defective in glucose utilization and transport 442. In addition to glucose, RF permease was inhibited by sucrose, maltose, trehalose, and methylglucoside and somewhat by 2 deoxyglucose, while fructose and mannose had no effect. Glucose also strongly inhibited uptake python python RF analog 8 piperidyl 10 1 d ribitylisoalloxazine, which competed with RF for uptake into python cell; although, against this to RF, it couldn’t were excreted by python cells into python medium. Thus, glucose inhibition python RF transport can’t be defined by activation python RF efflux. RF permease was synthesized only in media with glucosides, adding sucrose, maltose, methylglucoside, and melizitose, while cells grown on other substrates glucose, fructose, etc. didn’t take up RF from python medium at all, and an RF auxotroph in python glucose medium required high concentrations python exogenous RF 100 g/ml for growth 452.