Table 2.

Parameters for αIIbβ3–Peptide Complexes Obtained Using the Umbrella Sampling Simulations: ΔG_b, Binding Energy; Δx_b, Width of the Bound State Basin; Δx^‡, Transition State Distance^a

peptide	ΔGb, kcal/mol	Δx‡, nm	Δxb, nm
γC-12 and open αIIbβ3	13.5 (29.2)	1.9 (5.1)	0.75 (0.81)
γC-12 and closed αIIbβ3	13.9 (37.5)	2.2 (4.6)	0.71 (0.76)
cyclic RGDFK and open αIIbβ3	16.1	2.6	0.79
cyclic RGDFK and closed αIIbβ3	15.6	2.0	0.70

^aValues obtained without suppression of γC-12 forced unraveling are given in parentheses.