A method for producing L-glutamic acid by fermentation is provided, comprising culturing in a culture medium an L-glutamic acid producing microorganism of the genus Escherichia. According to this method a microorganism is cultered which is obtained by incorporating into a recipient strain of the genus Escherichia a hybrid plasmid having inserted therein a DNA fragment with the genetic information controlling the L-glutamic acid production, which fragment is derived from a donor strain of the genus Escherichia which is capable of producing L-glutamic acid.
The invention further comprises a method for producing a new microorganism of the genus Escherichia having high productivity for L-glutamic acid, according to which chromosomal DNA is obtained from a mutant strain of the genus Eschierichia which is capable of producing L-glutamic acid, the obtained DNA is treated with a restrio- tion endonuclease to obtain the DNA-fragment with the genetic information responsible for the L-glutamic acid synthesis, the DNA fragment is inserted into a plasmid obtained from a microorganism of the genus Eschierichia and the recombinant plasmid is incorporated into a microorganism of the genus Escherichia as a recipient organism.
本发明提供了一种通过发酵生产
L-谷氨酸的方法,包括在
培养基中培养产生
L-谷氨酸 的埃希氏菌属微
生物。根据这种方法,可以培养出一种微
生物,这种微
生物是通过将一种杂交质粒加入到埃希氏菌属的受体菌株中而获得的,这种杂交质粒中插入了具有控制
L-谷氨酸生产的遗传信息的 DNA 片段,该 DNA 片段来自埃希氏菌属的供体菌株,该供体菌株能够生产
L-谷氨酸。
本发明还包括一种生产
L-谷氨酸生产率高的埃希氏菌属新微
生物的方法,根据该方法,从能生产
L-谷氨酸的埃希氏菌属突变菌株中获得染色体 DNA、用
重组内切酶处理所获得的 DNA,以获得含有负责合成
L-谷氨酸的遗传信息的 DNA 片段,将该 DNA 片段插入从 Eschierichia 属微
生物中获得的质粒中,然后将
重组质粒作为受体
生物结合到 Escherichia 属微
生物中。