一株γ-聚谷氨酸合成菌的筛选与鉴定

Screening and identification of a novel γ-polyglutamic acid producing strain

摘要:

从土壤中筛选分离获得一株γ-聚谷氨酸合成菌PGS-1, 经鉴定为枯草芽孢杆菌(Bacillussubtilis), 在富含谷氨酸和葡萄糖的培养基中可大量合成γ-聚谷氨酸, 摇瓶发酵产量达26 g/L, 不同于大多文献报道的微生物合成的γ-聚谷氨酸具有较高的分子量, 该菌株合成的γ-聚谷氨酸分子量较低(3×10⁵?4×10⁵ kD), 分子量分布较窄, 可适用于低分子量要求的应用领域, 如作为药物的控缓释载体, 值得深入开发研究。

关键词:γ-聚谷氨酸, 筛选, 枯草芽孢杆菌, 摇瓶发酵

Abstract:

A novel γ-polyglutamic acid (γ-PGA) producing-strain Bacillus subtilis PGS-1 was isolated from soil, which could produced a large mount of γ-PGA in the medium containing glucose and glutamate. The highest yield 26 g/L of γ-PGA was obtained in flask culture. Compared with other reported γ-PGA producing-strain, γ-PGA derived from Bacillus subtilis PGS-1 had a lower molecular weight (3×10⁵?4×10⁵ kD) and a narrower polydispersity (1.3?2.0), which could endow γ-PGA a promising application, such as in the drug delivery system.

Key words:γ-polyglutamic acid, Screening, Bacillus subtilis, Flask culture