the vacuolar ph and the trans-tonoplast deltaph modifications induced by the activity of the two proton pumps h ( + ) -atpase and h ( + ) -ppase and by the proton exchanges catalyzed by the na ( + ) /h ( + ) and ca ( 2+ ) /h ( + ) antiports at the tonoplast of isolated intact vacuoles prepared from catharanthus roseus cells enriched in inorganic phosphate ( y mathieu et al 1988 plant physiol [ in press ] ) were measured using the ( 31 ) p nmr technique .
C0042219
vacuoles
C0007634
cells