Skip to main content

View full-text article in PMC

. Author manuscript; available in PMC: 2007 Mar 29.

Published in final edited form as: J Neurochem. 2004 Aug;90(4):970–978. doi: 10.1111/j.1471-4159.2004.02566.x

Table 4.

Dopamine binding to human tyrosine hydroxylase isoforms

	Unphosphorylated enzyme			Phosphorylated enzyme
Isoform	k_on^a (mM⁻¹ min⁻¹)	k_off^b (min⁻¹)	K_d^c (nM)	k_on^a (mM⁻¹ min⁻¹)	k_off^b (min⁻¹)	K_d^c (μM)
hTyrH₁	66.6 ± 3.0	< 0.00015	< 2.2	172 ± 7	0.024 ± 0.002	143 ± 15
hTyrH₂	43.2 ± 2.4	< 0.00015	< 3.5	198 ± 7	0.016 ± 0.001	82 ± 4
hTyrH₃	48.6 ± 2.4	< 0.00015	< 3.1	148 ± 7	0.012 ± 0.001	85 ± 9
hTyrH₄	55.2 ± 1.8	< 0.00015	< 2.7	145 ± 4	0.011 ± 0.001	78 ± 4
rat TyrH^c	312 ± 18	0.000041 ± 0.000004	0.13 ± 0.02	474 ± 2	0.10 ± 0.002	208 ± 20

^a

Conditions: 10% glycerol, 100 mM KCl, 50 mM HEPES, pH 7, 10°C.

^b

Conditions: 1 mM DHN, 60 μm dopamine, 10% glycerol, 100 mM KCl, 0.2 mM DTPA, 50 mM HEPES, pH 7, 10°C.

^d

From reference (McCulloch et al. 2001); determined at 15°C.