SUMMARY: B is one of the many strains able to utilize glutamate as a sole source of carbon. Sodium is an obligate requirement for glutamate transport by washed whole cells, but the affinity for sodium ( = 23 mM) is low. At pH 7.6, uptake of glutamate is rapid in 50 mM-sodium at 65 °C and obeys saturation kinetics with an apparent of 0.23 μ;M-glutamate and a of 12 nmol glutamate min (mg protein). The transport system is insensitive to osmotic shock and is specific for glutamate, with both the L- and D-isomers being transported. Uptake is very sensitive to inhibitors that collapse the membrane potential (Δψ) or the chemical gradient of sodium ions (ΔNa), but a transmembrane pH gradient (ΔpH) plays no role in the transport of glutamate. These results are therefore consistent with a membrane sodium/glutamate symport system.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error