title: A new procedure for fast isolation and purification of plastocyanin from the cyanobacterium Anabaena variabilis.
abstract: Methods are described for growing the cyanobacterium A. variabilis and for the isolation and purification of plastocyanin from the grown culture. Cell paste which had been stored at -35°C was suspended in 1 mM MES buffer, pH 6.5 and centrifuged. The supernatant was diluted to a conductivity of 0.12 mS, [Fe(CN)6](3-) added to a concentration of 0.5 mM and the solution loaded on a S Sepharose Fast Flow column. After elution and ultrafiltration, the plastocyanin containing fractions were reloaded on a S Sepharose Fast Flow column for final purification. A typical yield in three days from cells harvested from 3×20 l of medium was 32 mg plastocyanin with a minimum absorbance ratio A278/A597=1.14. This procedure is faster and the yield higher than for previous procedures.
authors.affiliation: Chemistry Department A, The Technical University of Denmark, Building 207, 2800, Lyngby, Denmark.
authors.forename: H E
authors.initials: HE
authors.lastname: Christensen
authors.forename: L S
authors.initials: LS
authors.lastname: Conrad
authors.forename: J
authors.initials: J
authors.lastname: Ulstrup