Sulfate reduction in higher plants: molecular evidence for a novel 5'-adenylylsulfate reductase.

ABSTRACT: Sulfate-assimilating organisms reduce inorganic sulfate for Cys biosynthesis. There are two leading hypotheses for the mechanism of sulfate reduction in higher plants. In one, adenosine 5'-phosphosulfate (APS) (5'-adenylysulfate) sulfotransferase carries out reductive transfer of sulfate from APS to reduced glutathione. Alternatively, the mechanism may be similar to that in bacteria in which the enzyme, 3'-phosphoadenosine-5'-phosphosulfate (PAPS) reductase, catalyzes thioredoxin (Trx)-dependent reduction of PAPS. Three classes of cDNA were cloned from Arabidopsis thaliana termed APR1, -2, and -3, that functionally complement a cysH, PAPS reductase mutant strain of Escherichia coli. The coding sequence of the APR clones is homologous with PAPS reductases from microorganisms. In addition, a

SUBMITTER: Setya A 

PROVIDER: S-EPMC24102 | biostudies-literature | 1996 Nov

REPOSITORIES: biostudies-literature