Premium
Modification of Photosystem II by phenylglyoxal
Author(s) -
Gardner Gary,
Allen Cheryl D.,
Paterson David R.
Publication year - 1983
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(83)80047-7
Subject(s) - phenylglyoxal , chemistry , thylakoid , photosystem ii , photosystem i , biophysics , arginine , electron transport chain , chloroplast , biochemistry , photosynthesis , stereochemistry , biology , amino acid , gene
Shipman [(1981) J. Theor. Biol. 90, 123–148] has recently noted that herbicides from various chemical classes which inhibit electron transport through Photosystem II have a flat polar component in the range 3–5 debye, and he suggests that this component of the herbicide interacts with a strong electric field across the protein binding site in the thylakoid. This polar portion of the binding site could be a salt bridge, the cationic end of which may be an arginine residue. Phenylglyoxal is a protein‐modifying reagent with specificity toward arginine residues. Pretreatment of chloroplast membranes with 50 mM phenylglyoxal for 30 min at 30°C completely abolished the ability to bind specifically [ 14 C]atrazine. Pretreatment with 50 mM phenylglyoxal also completely abolished the subsequent ability of the chloroplasts to carry out photosynthetic electron transport. These data provide strong evidence for the involvement of arginine residues in the binding and action of Photosystem II herbicides.