Inversion of allosteric effect of arginine on N-acetylglutamate synthase, a molecular marker for evolution of tetrapods

Table 1 Effects of L-arginine on the enzymatic activity of arginine-resistant and wild-type mouse NAGS.

	Specific Activity (μmol min^-1mg^-1)
Mouse NAGS		+1 mM Arginine
Wild-type	12.27 ± 0.19^a	25.56 ± 0.43
F121C	12.22 ± 0.15	13.08 ± 0.07
E354A	15.47 ± 0.22	15.28 ± 0.33
G360P	13.00 ± 0.12	12.57 ± 0.38
G362S	3.22 ± 0.01	3.19 ± 0.09

^aActivities are averages of three measurements and their associated standard errors

ISSN: 1471-2091