Table I.

Crystallographic data and refinement statistics

	CD45 D1D2 C828S and phosphopeptide complexes
	Polyoma middle T antigen	CD3 ζITAM-1
Crystallographic data
Space group	P2(1)	P2(1)
Cell parameters	a = 86.9 Å, b = 57.9 Å, c = 159.3 Å, β = 98.78	a = 86.0 Å, b 5 59.7 Å, c = 160.5 Å, β 5 99.58
Z	4	4
X-ray source	X12, BNL	X12, BNL
Resolution	30–2.9 Å	30–2.9 Å
Observations (n)	99,669	99,514
Unique reflections (complete)	32,025 (93.0%)	29,466 (81.5%)
Rsym a	0.079	0.071
Refinement statistics of current model
Resolution	30–2.9 Å	30–2.9 Å
Protein atoms (n)	9,457	9,416
Substrate atoms (n)	74	122
Rcryst (workb/freec)	0.263/0.306	0.258/0.315
Rmsd bond lengths	0.010 Å	0.010 Å
Rmsd bond angles	1.59°	1.57°

^aR_sym = Σ_h Σ_i|I_ih − <I_h>|/Σ_h Σ _i<I_h>, where <I_h> is the mean of the observations I_ih of reflection h.

^bR_working = Σ||F_obs| − |F_calc||/Σ|F_obs|.

^cR_free = R factor for a selected subset (5%) of the reflections that was not included in prior refinement calculations.