Figure 7
Comparison of solubility and activity of FumI produced in E. coli strains ArcticExpress(DE3) at 11°C and BL21(DE3) at 37°C. Aminotransferase FumI showed a higher amount of soluble enzyme in a Western blot (anti-His6-antibody; from 12% polyacrylamide SDS-PAGE gel) (A) and higher enzyme activity (B) when produced in E. coli ArcticExpress(DE3) at 11°C compared with E. coli BL21(DE3) at 37°C. Both host strains harbored plasmid pET-30a-AT144HIS for expression of fumI with a C-terminal 6xHis tag. (A) The molecular mass of aminotransferase FumI-HIS (48.3 kDa) is shown; (S) soluble and (I) insoluble fractions of E. coli cell lysates. (B) Initial enzyme velocities based on HFB1 deamination.