From: Microbial synthesis of poly-γ-glutamic acid: current progress, challenges, and future perspectives
Strains | Engineering methods | Fermentation medium | Production (g/L) | Ref. |
---|---|---|---|---|
B. licheniformis WX-02 | Expression of glr gene encoding glutamate racemase | Glucose, l-glutamic acid, sodium citrate, NH4Cl, MgSO4, K2HPO4, CaCl2, ZnSO4, MnSO4 | 14.38 | [75] |
B. amyloliquefaciens LL3 | Double-deletion of genes pgdS and cwlO | Sucrose, (NH4)2SO4, MgSO4, KH2PO4, K2HPO4 | 7.12 | [84] |
B. amyloliquefaciens LL3 | Deletion of genes (rocR, rocG, gudB, odhA) | Sucrose, (NH4)2SO4, MgSO4, KH2PO4, K2HPO4, | 5.68 | [85] |
B. subtilis ISW1214 | Bearing the plasmid-borne PGA synthetic system | Sucrose, NaCl, MgSO4, KH2PO4, NaHPO4,xylose | 9.0 | [47] |
E. coli BL21 | Cloning and overexpressing γ-PGA biosynthesis genes | Glucose, yeast extract, l-glutamic acid, (NH4)2SO4 | 3.7 | [76] |
E. coli JM 109 | Co-expressing γ-PGA synthetase and glutamate racemase | LB medium supplemented with l-glutamate or glucose | 0.65 | [48] |
B. amyloliquefaciens | Deletions of genes (epsA-O, sac, lps, pta, pgdS, cwlO, luxS, and rocG gene, expression of synthetic small regulatory RNAs which repressed the rocG and glnA gene | Sucrose, (NH4)2SO4, MgSO4, KH2PO4, K2HPO4 | 20.3 | [86] |
B. subtilis PB5249 | Knockout of genes (pgdS and ggt) | l-glutamic acid, citric acid, glucose, NH4Cl, K2HPO4, MgSO4·7H2O, FeCl3·6H2O, CaCl2·2H2O, MnSO4·H2O, pH 6.5 | 40 | [87] |
Bacillus licheniformis WX-02 | Enhanced expression of pgdS gene | Glucose, sodium glutamate, sodium citrate, NH4Cl, MgSO4, K2HPO4, CaCl2, ZnSO4, MnSO4 | 20.16 | [88] |
Corynebacterium glutamicum | Cloning and expressing γ-PGA biosynthesis genes | Glucose, (NH4)2SO4, KH2PO4, MgSO4·7H2O, FeSO4·7H2O, MnSO4·4H2O, soy protein hydrolysate, thiamine hydrochloride, CaCO3 | 18 | [54] |