Cloning and Expression of the γ-Polyglutamic Acid Synthetase Gene pgsBCA in Bacillus subtilis WB600

الملخص EN

To clone and express the γ-polyglutamic acid (γ-PGA) synthetase gene pgsBCA in Bacillus subtilis, a pWB980 plasmid was used to construct and transfect the recombinant expression vector pWB980-pgsBCA into Bacillus subtilis WB600.

PgsBCA was expressed under the action of a P43 promoter in the pWB980 plasmid.

Our results showed that the recombinant bacteria had the capacity to synthesize γ-PGA.

The expression product was secreted extracellularly into the fermentation broth, with a product yield of 1.74 g/L or higher.

γ-PGA samples from the fermentation broth were purified and characterized.

Hydrolysates of γ-PGA presented in single form, constituting simple glutamic acid only, which matched the characteristics of the infrared spectra of the γ-PGA standard, and presented as multimolecular aggregates with a molecular weight within the range of 500–600 kDa.

Expressing the γ-PGA synthetase gene pgsBCA in B.

subtilis system has potential industrial applications.