PAPS‐reductase of Escherichia coli

Abstract
The DNA of the gene complementing a PAPS‐reductase‐deficient strain of Escherichia coli was sequenced. The N‐terminal amino acid sequence of the purified PAPS‐reductase confirmed that cys H is the structural gene for this enzyme. The open reading frame extends 732 bases and encodes for a peptide of M r = 27927. The gene product is functionally active when supplemented with thioredoxin and immunologically related with the wild type enzyme.