Auxin regulation of a proton translocating ATPase in pea root plasma membrane vesicles. [Pisum sativum. L]
Pea root microsomal vesicles have been fractionated on a Dextran step gradient to give three fractions, each of which carries out ATP-dependent proton accumulation as measured by fluorescence quenching of quinacrine. The fraction at the 4/6% Dextran interface is enriched in plasma membrane, as determined by UDPG sterol glucosyltransferase and vanadate-inhibited ATPase. The vanadate-sensitive phosphohydrolase is not specific for ATP, has a K/sub m/ of about 0.23 millimolar for MgATP, is only slightly affected by K/sup +/ or Cl/sup -/ and is insensitive to auxin. Proton transport, on the other hand, is more specific for ATP, enhanced by anions (NO/sub 3//sup -/ > Cl/sup -/) and has a K/sub m/ of about 0.7 millimolar. Auxins decrease the K/sub m/ to about 0.35 millimolar, with no significant effect on the V/sub max/, while antiauxins or weak acids have no such effect. It appears that auxin has the ability to alter the efficiency of the ATP-driven proton transport.
- Research Organization:
- Univ. of Washington, Seattle
- DOE Contract Number:
- AT06-70ER73019
- OSTI ID:
- 6942370
- Journal Information:
- Plant Physiol.; (United States), Vol. 79:4
- Country of Publication:
- United States
- Language:
- English
Similar Records
Auxin effects on in vitro and in vivo protein phosphorylation in pea. [Pisum sativum]
Metabolism of inositol(1,4,5)trisphosphate by a soluble enzyme fraction from pea (Pisum sativum) roots
Related Subjects
ATP-ASE
ENZYME ACTIVITY
AUXINS
BIOCHEMICAL REACTION KINETICS
MICROSOMES
PROTON TRANSPORT
ANIONS
CATIONS
CELL MEMBRANES
CHLORIDES
DEXTRAN
ENZYME INHIBITORS
EXPERIMENTAL DATA
FLUORESCENCE
FRACTIONATION
GLYCOSYL TRANSFERASES
NITRATES
PEAS
PHOSPHOHYDROLASES
PLANT CELLS
POTASSIUM
QUENCHING
RESPONSE MODIFYING FACTORS
ROOTS
STEROLS
UDPG
VANADATES
ACID ANHYDRASES
ALKALI METALS
BLOOD SUBSTITUTES
CARBOHYDRATES
CELL CONSTITUENTS
CHARGED PARTICLES
CHARGED-PARTICLE TRANSPORT
CHLORINE COMPOUNDS
DATA
DRUGS
ELEMENTS
ENZYMES
FOOD
GLYCOSIDES
HALIDES
HALOGEN COMPOUNDS
HEMATOLOGIC AGENTS
HYDROLASES
HYDROXY COMPOUNDS
INFORMATION
IONS
KINETICS
LUMINESCENCE
MEMBRANES
METALS
NITROGEN COMPOUNDS
NUCLEOTIDES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANOIDS
OXYGEN COMPOUNDS
PLANT GROWTH REGULATORS
PLANTS
POLYSACCHARIDES
RADIATION TRANSPORT
REACTION KINETICS
SACCHARIDES
SEPARATION PROCESSES
STEROIDS
TRANSFERASES
TRANSITION ELEMENT COMPOUNDS
VANADIUM COMPOUNDS
VEGETABLES
550500* - Metabolism