title: Microheterogeneity of parsley plastocyanin.
abstract: A procedure for isolation of two iso-plastocyanins from parsley has been described here. Three consecutive chromatographic steps on DE-52-Whatman cellulose were applied for isolation of two total plastocyanin (PC) fractions, oxidized [PC(II)] and reduced [PC(I)]. By chromatofocusing of PC(II) on Polybuffer exchanger 74 two different plastocyanins, designated as plastocyanin a (PCa) and plastocyanin b (PCb), were obtained. The isoelectric points (pI) of PCa and PCb at 10 degrees C are 4.16 and 4.14, respectively. The complete amino acid sequences of PCa and PCb were determined. The two iso-proteins consist of 97 amino acid residues and differ only at sequence position 53, where Glu in PCa is replaced by Asp in PCb.
authors.affiliation: Central Laboratory of Biophysics, Bulgarian Academy of Sciences, Sofia.
authors.forename: M I
authors.initials: MI
authors.lastname: Dimitrov
authors.forename: A A
authors.initials: AA
authors.lastname: Donchev
authors.forename: T A
authors.initials: TA
authors.lastname: Egorov
mesh_terms: D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D006868:Hydrolysis; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D010940:Plant Proteins / Q000302:isolation & purification*; D010944:Plants / Q000378:metabolism; D010970:Plastocyanin / Q000235:genetics / Q000302:isolation & purification*; D012689:Sequence Homology, Nucleic Acid
chemical_list: D010940:Plant Proteins; D010970:Plastocyanin