THE EFFECTS OF STRUCTURAL DEGRADATION ON THE COUPLED PHOTOCHEMICAL ACTIVITIES OF ISOLATED CHLOROPLASTS,
Abstract
Isolated washed chloroplasts were degraded by sonication or lipolytic enzymes and the inhibition of photophosphorylation coupled to photoreduction was measured. Sonication, pancreatic lipase and phospholipase A inhibited photophosphorylation to a considerably greater extent than photoreduction. The enzymes did not inhibit phenazine methosulfate-mediated phosphorylation as much as the coupled phosphorylation with ferricyanide. This differential inhibition of phosphorylation could not be accounted for by any type of ATPase activity. Wheat germ lipases, which best hydrolyze lipids with short fatty acid chains, did not affect the photoreactions. Some poorer-grade preparations were contaminated with an ATPase which could account for some uncoupling. The data support the hypothesis that, as with mitochondria, a more complex phospholipoprotein structure is necessary for the coupled reactions than for electron transport alone. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 13, 1964
- Accession Number
- AD0620594
Entities
People
- Jonathan Gressel
- Mordhay Avron
Organizations
- Weizmann Institute of Science