Cyclic and noncyclic photophosphorylation in isolated guard cell chloroplasts from Vicia faba L
High rates of both cyclic and noncyclic photophosphorylation were measured in chloroplast lamellae isolated from purified guard cell protoplasts from Vicia Faba L. Typical rates of light-dependent incorporation of /sup 32/P into ATP were 100 and 190 micromoles ATP per milligram chlorophyll per hour for noncyclic (water to ferricyanide) and cyclic (phenazine methosulfate) photophosphorylation, respectively. These rates were 50 to 80% of those observed with mesophyll chloroplasts. Noncyclic photophosphorylation in guard cell chloroplasts was completely inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea supporting the notion that photophosphorylation is coupled to linear electron flow from photosystem II to photosystem I. Several lines of evidence indicated that contamination by mesophyll chloroplasts cannot account for the observed photophosphorylation rates. A comparison of the photon fluence dependence of noncyclic photophosphorylation in mesophyll and guard cell chloroplasts showed significant differences between the two preparations, with half saturation at 0.04 and 0.08 millimole per square meter per second, respectively.
- Research Organization:
- Stanford Univ., CA (United States)
- OSTI ID:
- 5681064
- Journal Information:
- Plant Physiol.; (United States), Vol. 78:2
- Country of Publication:
- United States
- Language:
- English
Similar Records
Electrophoretic assay for ribulose 1,5-bisphosphate carboxylase/oxygenase in guard cells and other leaf cells of Vicia faba L
Isolation of guard cell protoplasts from mechanically prepared epidermis of Vicia faba leaves
Related Subjects
CHLOROPLASTS
PHOSPHORYLATION
VICIA
ATP
BIOCHEMICAL REACTION KINETICS
CHLOROPHYLL
CYANIDES
ELECTRON TRANSFER
EXPERIMENTAL DATA
INHIBITION
IRON COMPOUNDS
ORGANIC CHLORINE COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHENAZINE
PHOSPHORUS 32
PLANT CELLS
SULFONIC ACID ESTERS
VISIBLE RADIATION
AZINES
BACTERIA
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CHEMICAL REACTIONS
DATA
DAYS LIVING RADIOISOTOPES
ELECTROMAGNETIC RADIATION
ESTERS
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
INFORMATION
ISOTOPES
KINETICS
LEGUMINOSAE
LIGHT NUCLEI
MICROORGANISMS
NUCLEI
NUCLEOTIDES
NUMERICAL DATA
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PHOSPHORUS ISOTOPES
PHYTOCHROMES
PIGMENTS
PLANTS
PORPHYRINS
PROTEINS
PYRAZINES
RADIATIONS
RADIOISOTOPES
REACTION KINETICS
RHIZOBIUM
TRANSITION ELEMENT COMPOUNDS
550501* - Metabolism- Tracer Techniques