Figure 7.

Comparison of the immobilization method and traditional method to obtain PNGase F. (A) Flow chart showing the procedure of the immobilization method. The cell culture of E. coli containing the immobilization plasmid was grown for 2 h, and infected by Soc⁻ phage at a multiplicity of infection of 1. After infection, the phage amplified and PNGase F self-assembled. 3 h of incubation time ensured complete amplification and assembly of phage in the culture. The phage was isolated from the culture by differential centrifugations. The total time required was 7 h. (B) Flow chart of the procedure to produce PNGase F in the traditional way. Cell culture with the inducible PNGase F gene was grown to an appropriate density and PNGase F overexpression was induced for a time period ranging from 3 h to overnight. The cells were harvested and lysed, followed by purification steps including affinity chromatography, ion-exchange and/or gel filtration. Two days were required to produce PNGase F in the traditional way.