The expression of the metA gene coding for the first enzyme in the methionine biosynthethic pathway was studied in wild-type and in deregulated strains of Escherichia coli K-12 carrying the gene on multicopy plasmids. We looked at (a) in vitro activity of the metA product-The enzyme homoserine transsuccinylase (HTS); (b) resistance of cells carrying metA plasmids to the analogue α-methylmethionine which specifically inhibits HTS, and (c) the metA polypeptide in mini cells. The results indicate that the Mr value of the polypeptide synthesized by the metA gene is 40 000. The synthesis of HTS, even when the metA gene is cloned on a multicopy plasmid, is under the negative control of the regulatory metJ gene.
|Number of pages||5|
|Journal||FEMS Microbiology Letters|
|State||Published - 1984|
- metA gene
- methionine biosynthesis