FIG. 5.

Hydrolysis of azocoll by GelE and site-specific mutants as a function of time measured by the absorbance of released azocoll dye. The assay was carried out with FA2-2 strains carrying plasmids pML28 (vector alone) (♦), pML29 (GelE wild type) (▪), pML38 (GelE E303P) (▵), pML39 (GelE D304P) (○), pML40 (GelE I305P) (⋄), and pML41 (GelE Q306P) (•). The data are the averages of two independent experiments; the error bars indicate the standard deviations. Each data point is the average of triplicate measurements. OD₅₅₀, optical density at 550 nm.