TABLE 1.

Effects of metal ions on GspInv activity.

Metal ions	1 mM	5 mM	10 mM
None	100.0	100.0	100.0
Mg2+	102.6 ± 1.8	90.7 ± 8.5	82.2 ± 6.9
Ba2+	106.7 ± 11.1	108.1 ± 3.9	109.7 ± 4.4
Ca2+	111.9 ± 4.9	112.7 ± 3.0	120.9 ± 3.7
Co2+	102.1 ± 6.2	85.1 ± 7.6	72.8 ± 11.1
Ni2+	92.4 ± 1.4	78.7 ± 4.2	57.9 ± 2.3
Mn2+	153.8 ± 3.6	143.2 ± 1.6	113.3 ± 17.2
Cu2+	52.1 ± 2.3	22.3 ± 1.9	16.7 ± 1.4
Fe3+	88.6 ± 4.6	89.2 ± 3.1	81.3 ± 2.4

Sulfates are used as the target mental ion donators. Invertase activity was determined at 45°C in citrate-phosphate buffer (50 mM, pH 5.0) using sucrose as the substrate. The data presented are the average values from triplicate technical repeats of measurements.