TABLE 1.

Parameters derived from fitting dose-response data^a

Condition	No. of modifications (modification)	Parameterb
		[Asp]1/2 (μM)	vu (nM/s)	vs (nM/s)	n
Vesicles	0 (EEEE)	2.2 ± 0.4	1.5 ± 0.1	2.6 ± 0.1	1.1 ± 0.3
	1 (QEEE)	3.0 ± 0.4	1.6 ± 0.2	3.7 ± 0.4	1.3 ± 0.2
	2 (QEQE)	3.2 ± 1.3	1.2 ± 0.1	2.9 ± 0.1	1.2 ± 0.1
	3 (QEQQ)	7.3 ± 1.6	0.3 ± 0.1	0.7 ± 0.1	1.3 ± 0.05
	3 (QQEQ)	8.6 ± 0.8	0.5 ± 0.05	3.0 ± 0.4	1.2 ± 0.2
1 dimer/disc	0 (EEEE)	1.8 ± 0.5	2.8 ± 0.5	5.1 ± 0.3	1.2 0± 0.1
	1 (QEEE)	1.9 ± 0.6	3.0 ± 0.1	6.1 ± 0.05	1.1 ± 0.2
	2 (QEQE)	2.5 ± 0.7	3.2 ± 0.5	5.2 ± 0.9	1.2 ± 0.1
	3 (QEQQ)	3.2 ± 0.4	1.1 ± 0.05	3.1 ± 0.05	1.3 ± 0.1
	3 (QQEQ)	5.7 ± 1.7	1.9 ± 0.8	4.1 ± 1.3	1.2 ± 0.2
∼3 dimers/disc	0 (QEEE)	0.8 ± 0.3	2.3 ± 0.2	4.8 ± 0.5	1.0 ± 0.2
	1 (QEEE)	1.5 ± 0.7	2.8 ± 0.4	5.2 ± 0.8	1.1 ± 0.1
	2 (QEQE)	2.5 ± 0.4	2.7 ± 0.1	5.2 ± 0.1	0.9 ± 0.05
	3 (QEQQ)	7.1 ± 1.4	0.9 ± 0.05	3.0 ± 0.1	1.1 ± 0.3
	3 (QQEQ)	3.6 ± 0.7	1.0 ± 0.1	3.4 ± 0.3	1.0 ± 0.2

^aData shown in Fig. 5 and 6 were fit to the relationship v = v_u + (v_s[Asp]ⁿ)/([Asp]_1/2ⁿ + [Asp]ⁿ) where v_u is the “unstimulated” initial rate (i.e., the rate in the absence of aspartate), v_s is the “maximally stimulated” initial rate (i.e., the rate at saturating aspartate), [Asp]_1/2 is the aspartate concentration at which stimulation of the initial rate is half maximal, and n is the Hill coefficient.

^bThe mean values and standard deviations for these parameters derived from fitting dose-response data from at least three independent experiments determining initial rates of methylation for Tar with 0 to 3 adaptational modifications and in conditions with many potentially interacting neighboring receptor dimers (vesicles), no potentially interacting neighboring receptor dimers (1 dimer/disc), or few potentially interacting neighboring receptor dimers (∼3 dimers/disc) are shown.