. Author manuscript; available in PMC: 2010 Apr 21.

Published in final edited form as: Biochemistry. 2009 Apr 21;48(15):3378–3386. doi: 10.1021/bi900057g

Table 3.

Comparison of Imidazole and 2-Amino-imidazole as Activators^a

	Imidazole			2-Aminoimidazole
	k_cat(min⁻¹)	K_m (mM)	k_cat/K_m (M⁻¹ s⁻¹)	k_cat (min⁻¹)	K_m (mM)	k_cat/K_m (M⁻¹ s⁻¹)
R388A Src^b	21.5 ± 0.7	9.3 ± 0.8	40 ± 10	11.0 ± 0.3	6.8 ± 0.5	27 ± 2
R388A/W428Y Src^b	8.30 ± 0.02	16 ± 1	8.7 ± 0.8	5.56 ± 0.03	6 ± 1	16 ± 3
R367A AblKD^c	460 ± 20	8.5 ± 0.9	900 ± 100	350 ± 20	5.3 ± 0.9	1100 ± 200
R367A/W407Y AblKD^d	NS (> 60)	NS (> 30)	26 ± 7

Reactions were performed at 30° at pH 7.4 with 10 mM MgCl₂. NS: No Saturation. If no value is given, then the constants were not measured.

50 mM Tris, 10 mM DTT, 200 µg/mL BSA, 400 µM ATP, 1 mg/mL PGT, 0.15 mCi/mL [γ−³²P]ATP

100 mM Tris, 1 mM ATP, 440 µM Abltide, 0.1 U/µL pyruvate kinase, 0.05 U/µL lactate dehydrogenase, 1 mM phosphoenolpyruvate, 150 µM NADH, and 0.5 mM Na₃VO₄

100 mM Tris, 1 mM ATP, 1.5 mM Abltide, 0.1 U/µL pyruvate kinase, 0.05 U/µL lactate dehydrogenase, 1 mM phosphoenolpyruvate, 150 µM NADH, and 0.5 mM Na₃VO₄