title: A thioredoxin-activated fructose-1,6-bisphosphatase from the cyanobacterium Synechococcus 6301.
abstract: Fructose-1,6-bisphosphatase was isolated from the cyanobacterium Synechococcus 6301 by acid precipitation, ammonium-sulfate fractionation, and Sephadex gel chromatography. The purified enzyme needed thiols and MgCl2 for activity. The following Km-values were obtained: a) for fructose-1,6-bisphosphate: 1.7 mM; b) for MgCl2: 12.5 mM; c) for dithiocrythritol: 0,56 mM; d) for glutathione: 14 mM; e) for mercaptoethanol: 22 mM; f) for cysteine: 50 mM. Thioredoxin B isolated from this organism will activate this fructose-1,6-bisphosphatase. The Km of thioredoxin B for this fructose-1,6-bisphosphatase was determined to be 1.7 μM, endicotiy that thioredoxin might activate the fructose-1,6-bisphosphatase in Synechococcus in vivo.
authors.affiliation: Botanisches Institut, Universität München, Menzinger Str. 67, D-8000, München 19, Federal Republic of Germany.
authors.forename: A
authors.initials: A
authors.lastname: Schmidt