title: Phenazine-1-carboxylic acid production in a chromosomally non-scar triple-deleted mutant Pseudomonas aeruginosa using statistical experimental designs to optimize yield.
abstract: We constructed a non-scar triple-deleted mutant Pseudomonas aeruginosa to improve phenazine-1-carboxylic acid (PCA) yield and then optimized the culture conditions for PCA production. Using a non-scar deletion strategy, the 5'-untranslated region of the phz1 gene cluster and two genes, phzM and phzS, were knocked out of the P. aeruginosa strain M18 genome. The potential ability for high-yield PCA production in this triple-deleted mutant M18MSU1 was successfully realized by using statistical experimental designs. A 2(5-1) fractional factorial design was used to show that the three culture components of soybean meal, corn steep liquor and ethanol had the most significant effect on PCA production. Using a central composite design, the concentration of the three components was optimized. The maximum PCA production was predicted to be 4,725.1 mg/L. With the optimal medium containing soybean meal 74.25 g/L, corn steep liquor 13.01 g/L and ethanol 21.84 ml/L, a PCA production of 4,771.2 mg/L was obtained in the validation experiments, which was nearly twofold of that before optimization and tenfold of that in the wild-type strain. This non-scar triple-deleted mutant M18MSU1 may be a suitable strain for industrial production of this biologically synthesized fungicide due to its high PCA production, presumed safety, thermal adaptability and cost-effectiveness.
authors: SKLMM, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, People's Republic of China.
authors: Xilin
authors: X
authors: Du
authors: Yaqian
authors: Y
authors: Li
authors: Wanping
authors: W
authors: Zhou
authors: Quan
authors: Q
authors: Zhou
authors: Haiming
authors: H
authors: Liu
authors: Yuquan
authors: Y
authors: Xu
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D002876:Chromosomes, Bacterial / Q000235:genetics*; D003470:Culture Media / Q000378:metabolism; D017353:Gene Deletion; D010619:Phenazines / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000378:metabolism*; D012107:Research Design; D017384:Sequence Deletion
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D010619:Phenazines; C037165:1-phenazinecarboxylic acid