title: Sulfate reduction in Catharanthus roseus (L.) : Identification and subcellular localization of a particulate adenosine 5'-phosphosulfate-reducing activity in cells from cell suspension cultures.
abstract: Cell homogenates from Catharanthus roseus (L.) G. Don. grown S-autotrophically on sulfate in the dark are capable of reducing adenylysulfate (APS) to cysteine. This reduction required a particulate protein fraction from the cell extract and reduced ferredoxin as the electron donor. The protein fraction (MW 700,000±50,000) was found to contain Fd:NADP(+) reductase, glutathione reductase and an unspecific dithiol reductase, and APS-sulfotransferase and thiosulfonate reductase activity. Resolution into these individual enzyme activities led to a non-restorable loss of the APS reducing activity. It was observed that a slow gradual decay of the APS reducing activity was accompanied by a likewise slow generation of a ferredoxin-dependent sulfite reductase.
authors.affiliation: Abteilung für Biologie der Ruhr-Universität, Postfach 102148, D-4630, Bochum 1, Federal Republic of Germany.
authors.forename: H
authors.initials: H
authors.lastname: Urlaub
authors.forename: G
authors.initials: G
authors.lastname: Jankowski