Genetic engineering of Pseudomonas chlororaphis GP72 for the enhanced production of 2-Hydroxyphenazine

Scientific Achievement                                        

We constructed an engineered strain named GP72ND3-pBbB5K-aroE-aroD-aroB-phzC-tktA-ppsA that increased the 2-OH-PHZ production in P. chlororaphis GP72 by 99-fold to 450.4 mg/L.

Significant and Impact

The 2-OH-PHZ production of P. chlororaphis GP72 was greatly improved through disruption of four negative regulatory genes and overexpression of six key genes, and it is shown that P. chlororaphis GP72 could be modified as a potential cell factory to produce 2-OH-PHZ and other phenazine biopesticides by genetic and metabolic engineering..

Research Details

•Four negative regulatory genes (pykF, rpeA, rsmE and lon) were firstly knocked out of the strain GP72 genome stepwise. The yield of 2-OH-PHZ improved more than 60 folds and increased from 4.5 to about 300 mg/L..

•Six key genes (ppsA, tktA, phzC, aroB, aroD and aroE) selected from the gluconeogenesis, pentose phosphate and shikimate pathways which used to enhance the shikimate pathway were overexpressed to improve the production of 2-OH-PHZ. At last a genetically engineered strain that increased the 2-OH-PHZ production by 99-fold to 450.4 mg/L was obtained.