Myo-Inositol transport in Klebsiella aerogenes. scyllo-Inositol, a non-metabolizable substrate for the study of the myo-inositol transport system.
1. Scyllo-Inositol is transported against a concentration gradient by Klebsiella aerogenes, but is not metabolized. 2. The apparent KT of scyllo-inositol is 0.05 X 10(-3) M while that of myo-inositol is 0.23 X 10(-3) M. The V values are respectively 32 and 12 nmol min(-1) mg cells(-1) (dry weight). 3. Both cyclitols bind to the same carrier, since typical competitive inhibition kinetics are observed. 4. Neither phosphoenolpyruvate phosphotransferase nor a periplasmic binding protein seems to be involved in the scyllo-inositol transport system. 5. The induction of the transport system is not repressed by malate, furmarate, citrate, succinate or pyruvate; however, acetate represses the induction. The activity of the transport system is increased when the growth medium is supplemented with adenosine 3':5'-monophosphate.
D001693:Biological Transport, Active; D002352:Carrier Proteins / Q000378:metabolism; D007294:Inositol / Q000378:metabolism*; D007536:Isomerism; D007700:Kinetics; D007711:Klebsiella pneumoniae / Q000378:metabolism*; D013696:Temperature
D002352:Carrier Proteins; D007294:Inositol