Table 1. NOE Upper Bound Violations Δ_ij (eq 14) for Different Isomerization States of BK^a.

state	atoms		NOE intensity	Δij [Å]
CCC	Phe5, H	Pro3, HA	vw	0.6
	Arg9, H	Pro7, HA	vw	0.1
CCT	Phe5, H	Pro3, HA	vw	0.7
CTC	Phe8, H	Pro7, HD2b	w	1.4
TCC	Phe5, H	Pro3, HA	vw	0.6
	Arg9, H	Pro7, HA	vw	0.2
TCT	Phe5, H	Pro3, HA	vw	0.8
	Arg9, H	Pro7, HA	vw	0.2
TTC	Arg9, H	Pro7, HA	vw	0.3

^aThe isomerization states of BK are labeled TTT, TTC, TCT, CTT, TCC, CTC, CCT, and CCC, where the letters “T” and “C” refer to the trans and cis isomerization states, respectively, of single Pro residues, and the first, second, and third positions refer to Pro2, Pro3, and Pro7, respectively. No violations are observed for states CTT and TTT. NOE intensities are given as strong (s), medium (m), weak (w), or very weak (vw), and corresponding experimental upper bounds¹⁹ were 3, 3.5, 4, or 4.5 Å, respectively.

^bStereospecific assignment to HD2 was made based on violations observed for HD3 in all sampled states.