Production method of polyglutamic acid independent of glutamic acid

The invention relates to the field of microorganisms, and discloses a glutamic acid-independent polyglutamic acid production method which comprises the following steps: transferring a strain into a liquid seed culture medium, and carrying out shake culture for 16-20 hours until the medium logarithmic growth stage; and inoculating the cultured seeds into a fermentation culture medium according to a volume ratio of 5-10%, fermenting for 24-48 hours, and detecting the content of polyglutamic acid. In the traditional production method, the preparation of polyglutamic acid depends on glutamic acid as a raw material. However, the strain adopted by the invention can synthesize polyglutamic acid without glutamic acid, so that the supply cost of glutamic acid is saved, the production cost is reduced, another beneficial thought is provided for industrial production of polyglutamic acid, meanwhile, by optimizing culture conditions and a culture medium, the yield of polyglutamic acid can be increased, and the method is s