Table 3. Kinetic parameters of esterases from workers of Solenopsis invicta and S. richteri on β-naphthyl acetate (β -NA)a.
| Species | Colony | Km (μM) | Vmax (μmol/min/ant) | Vmax (μmol/min/mg protein) |
|---|---|---|---|---|
| S. invicta | 12 | 9.90 ± 2.04 b | 11.71 ± 1.94 b | 60.96 ± 9.62 b |
| 288 | 20.45 ± 2.18 a | 18.59 ± 2.20 a | 112.45 ± 9.68 a | |
| 295 | 15.16 ± 1.85 ab | 14.49 ± 1.79 ab | 95.62 ± 8.12 ab | |
| S. richteri | 298 | 11.27 ± 0.65 ab | 5.77 ± 0.34 a | 39.01 ± 7.02 a |
| 303 | 7.13 ± 2.61 b | 6.94 ± 2.18 a | 49.97 ± 1.54 a | |
| 6 | 14.38 ± 1.39 a | 8.22 ± 0.62 a | 78.71 ± 17.34 a |
aThe difference in mean Km values is not significant between two ant species (t = −1.26, P = 0.23). Solenopsis invicta has significantly greater ant based Vmax (μmol/min/ant) and protein based Vmax (μmol/min/mg protein) than S. richteri (ant based: t = −5.08, df = 15, P = 0.0095; protein based: t = −2.20, df = 15, P = 0.044). Within a species, means followed by the different letter are significantly different (P < 0.05).