title: Chemical modification and cross-linking as probes of regions on ferredoxin involved in its interaction with ferredoxin: NADP reductase.
abstract: Ferredoxin which had been modified with glycine ethylester in the presence of a water-soluble carbodiimide to the extent of one carboxyl-group modified per ferredoxin was subjected to peptide mapping in an attempt to locate the site(s) of modification. The peptide mapping was done by HPLC and analysis of the resulting chromatogram allowed assignment of peaks to various segments in the amino acid sequences of the two isozymes of ferredoxin. The modified ferredoxin appeared to be a mixture of ferredoxin derivatives in which modification had occurred in three areas of the molecule. Although unable to identify the specific residues modified, it has been shown that modification is localized in the regions of residues 26-30, 65-70, and 92-94. The possibility that these regions of ferredoxin may define its binding site for ferredoxin: NADP reductase is discussed. Peptide mapping studies on a covalently linked adduct between ferredoxin and ferredoxin: NADP reductase also support these regions of ferredoxin as being important in the interaction between the two proteins.
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002851:Chromatography, High Pressure Liquid; D010450:Endopeptidases / Q000378:metabolism; D005288:Ferredoxins / Q000378:metabolism*; D007527:Isoenzymes / Q000032:analysis; D008958:Models, Molecular; D008968:Molecular Conformation; D010088:Oxidoreductases / Q000378:metabolism*; D010446:Peptide Fragments / Q000032:analysis; D012697:Serine Endopeptidases; D013820:Thermolysin / Q000378:metabolism; D014675:Vegetables
chemical_list: D005288:Ferredoxins; D007527:Isoenzymes; D010446:Peptide Fragments; D010088:Oxidoreductases; C028878:ferredoxin-NAD+ reductase; D010450:Endopeptidases; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase; D013820:Thermolysin