2.6.99.3 | synthesis |
expression of a D-cycloserine biosynthetic gene cluster consisting of 10 open reading frames (dcsA to dcsJ) from Streptomyces lavendulae ATCC 11924 in Escherichia coli. When L-serine and hydroxyurea, the precursors of D-cycloserine, are incubated together with the Escherichia coli resting cell suspension, the cells produce significant amounts of D-cycloserine (350 microM). To increase the productivity, the dcsJ gene, which might be responsible for the excretion, is connected downstream of the four genes, resulting in production of D-cycloserine at 660 microM. To repress the side catalytic activity of DcsD, i.e. the formation of L-cysteine from O-acetylserine and H2S, Escherichia coli chromosomal cysJ and cysK genes, encoding the sulfite reductase alpha subunit and O-acetylserine sulfhydrylase, respectively, are disrupted. The final strain produces 980 microM D-cycloserine |
-, 737505 |