Improved Production of Enzymes, Which Are Expressed under the Pho Regulon Promoter, in thermfGene (encoding ribosome modulation factor) Disruptant ofEscherichia coli

Using a DNA macroarray, we investigated the effects of rmf gene (encoding ribosome modulation factor) disruption on gene expression profiles in Escherichia coli. This strain showed a phosphate-starvation-like response in gene expression even under phosphate sufficient conditions; significant upregulation of the Pho regulon genes was observed. Further, the production of alkaline phosphatase, a product of the Pho regulon gene, phoA, increased in the rmf disruptant under a Pi sufficient condition. Furthermore, production of PhoC acid phosphatase/nucleoside pyrophosphate phosphotransferase derived from Morganella morganii also increased significantly in the rmf disruptant. We concluded that host modification by the rmf gene disruption has potential benefit in industrial enzyme production using Escherichia coli.