Glycine uptake into barley mesophyll vacuoles is regulated but not energized by ATP.


[U-(14)C]glycine uptake into barley (Hordeum vulgare cv Hasso) vacuoles was investigated. Glycine (2 millimolar) transport was stimulated two- to fourfold by NaATP. Stimulation was saturable with respect to ATP (1 millimolar) and linear up to 20 millimolar glycine. Stimulation by NaATP was suppressed by Mg(2+) in equimolar amounts. Neither MgATP nor Mg-inorganic pyrophosphate had any effect on basal transport rate. Thus, the proton motive force can be excluded as the driving force. Uncouplers (valinomycine/carbonylcyanide-m-chlorophenylhydrazone) inhibited the basal rate up to 30% but had no influence on NaATP-stimulated uptake. Vanadate had no effect on either basal or NaATP-stimulated uptake. Nonhydrolyzable ATP analogs (adenylyl(beta, gamma-methylen)-diphosphate or adenylyl-imidodiphosphate) stimulated comparable to NaATP. Other nucleotides (UTP, ADP) had no effect. Some evidence exists that other amino acids (arginine, alanine, isoleucine, phenylalanine) are transported to a certain extent by a similar mechanism. The results indicate a high capacity channel-like translocator that is regulated but not energized by ATP.


Citations per Year

210 Citations

Semantic Scholar estimates that this publication has 210 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{Goerlach1992GlycineUI, title={Glycine uptake into barley mesophyll vacuoles is regulated but not energized by ATP.}, author={J Goerlach and I Willms-Hoff}, journal={Plant physiology}, year={1992}, volume={99 1}, pages={134-9} }