title: Inhibition of chloroplast reactions with phenylmercuric acetate.
abstract: Phenylmercuric acetate is a selective inhibitor of the photosynthetic activities of isolated spinach (Spinacia oleracea) chloroplasts. At 5 mum concentration of phenylmercuric acetate, photophosphorylation is inhibited. At 33 mum phenylmercuric acetate, ferredoxin is inactivated. Ferredoxin-NADP oxidoreductase is 50% inhibited at 100 mum phenylmercuric acetate. Photosystem II reactions are 50% inhibited at 150 mum phenylmercuric acetate and very much higher cooncentrations-500 mum-are needed to approach complete inhibition. Phenylmercuric acetate inhibition of photosystem II appears to be selective, blocking a site between the 3-(3,4-dichlorophenyl)-1,1-dimethyl urea sensitive site and the site inactivated by high concentrations of tris buffer.
authors.affiliation: Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907.
authors.forename: R C
authors.initials: RC
authors.lastname: Honeycutt
authors.forename: D W
authors.initials: DW
authors.lastname: Krogmann