Fig 1.
Effect of assay duration on the optimum enzyme temperature.
A) Relative activity of Sfβgly during the assays at different temperatures. (purple cross) 29°C; (blue circle) 33°C; (blue diamond) 37°C; (red square) 42°C; (green triangle) 46°C. Vertical dashed lines highlight three different assay times (20, 60 and 120 min). The relative activity at 42 and 37°C at these assay times is presented in the rounded boxes, illustrating the shift of the optimum temperature throughout the assay. B) Changes in the optimum temperature resulting from modifications of the enzyme assay duration. The red circle and arrows highlight the decrease in the enzyme activity at 42°C, which was the optimum temperature in the shorter assay. The blue circle and arrow illustrate the increase in the relative activity at 37°C, which was the optimum temperature only for longer assay times. The enzyme concentration was 140 nM. This complete dataset (mean relative activities and respective deviations) is presented on S1 Table.
Fig 2.
Effect of the enzyme concentration on the optimum temperature.
A) Relative activity of Sfβgly during the assays at different temperatures in experiments performed using 280 nM Sfβgly and B) 85 nM Sfβgly. (purple cross) 29°C; (blue circle) 33°C; (blue diamond) 37°C; (red square) 42°C; (green triangle) 46°C. Inserts show the optimum temperature plot for 20-min assays at each enzyme concentration. Comparison of the inserted plots illustrates the optimum temperature shift due to enzyme dilution. This complete dataset (mean relative activities and respective deviations) is presented on S2 Table.
Fig 3.
Effect of assay duration on bglTm activity at different temperatures.
A) Relative activity of bglTm throughout the assay at different temperatures. (purple cross) 29°C; (blue circle) 33°C; (blue diamond) 37°C; (red square) 42°C; (green triangle) 46°C. B) Effect of assay time on the relative activity. The enzyme concentration was 7.5 nM. This complete dataset (mean relative activities and respective deviations) is presented on S3 Table.