TY - JOUR
AU - Vianello,, Angelo
AB - Abstract Radish (Raphanus sativus L.) microsomal vesicles show a vanadate- ánd nitrate-insensitive, and imidodiphosphate-sensitive electrogenic transport of protons dependent upon addition of inorganic pyrophosphate (PP) or ADP. The activity is detectable in preparations from 24 h-old seedlings and increases about 3 fold in vesicles from 72 h-old seedlings. The ADP-dependent proton uptake, being prevented by inorganic pyrophosphatase, used as a PP scavenging system, can be ascribed to enzymes utilizing ADP and producing PP which appears the only substrate for the proton pumping PPase. The H+-PPase has a Km of ca. 10 μM for the translocating function and 20 μM for the hydrolytic activity. It has a pH optimum near to 7.0 and is stimulated by certain monovalent cations (K+, Rb+ and Cs+). The majority of this activity is associated with a high density (35–45% sucrose interface) fraction which is enriched for vanadate-sensitive, nitrate-insensitive ATPase activity. This content is only available as a PDF. © 1990. The Japanese Society of Plant Physiologists (JSPP)
TI - Proton Pumping Pyrophosphatase in a High Density Fraction of Radish Microsomes
JO - Plant and Cell Physiology
DO - 10.1093/oxfordjournals.pcp.a077901
DA - 1990-01-01
UR - https://www.deepdyve.com/lp/oxford-university-press/proton-pumping-pyrophosphatase-in-a-high-density-fraction-of-radish-3VvtYSzQhA
SP - 261
EP - 266
VL - 31
IS - 2
DP - DeepDyve
ER -