Table 2. Kinetic parameters of esterases from workers of Solenopsis invicta and S. richteri on α-naphthyl acetate (α -NA)a.
| Species | Colony | Km (μM) | Vmax (μmol/min/ant) | Vmax (μmol/min/mg protein) |
|---|---|---|---|---|
| S. invicta | 12 | 12.29 ± 1.68 b | 12.79 ± 2.24 b | 66.11 ± 9.73 b |
| 288 | 20.01 ± 1.12 a | 21.15 ± 0.73 a | 129.48 ± 10.05 a | |
| 295 | 16.37 ± 1.02 ab | 14.85 ± 1.97 ab | 98.11 ± 9.33 ab | |
| S. richteri | 298 | 13.74 ± 0.23 a | 5.94 ± 0.37 b | 39.95 ± 6.38 b |
| 303 | 12.65 ± 2.20 a | 4.69 ± 1.22 b | 66.88 ± 3.81 ab | |
| 6 | 16.81 ± 1.49 a | 8.78 ± 0.47 a | 85.74 ± 21.31 a |
aThe difference in Km values between two ant species is not significant (t = −0.79, df = 16, P = 0.44). Solenopsis invicta has significantly greater ant based Vmax (μmol/min/ant) than S. richteri (t = −5.33, df = 16, P < 0.0001). Solenopsis invicta has greater protein based Vmax (μmol/min/mg protein) than S. richteri and the difference is very close to be statistically significant (t = −2.08, df = 16, P = 0.054). Within a species, means followed by the different letter are significantly different (P < 0.05).