. Author manuscript; available in PMC: 2010 Oct 28.

Published in final edited form as: J Am Chem Soc. 2009 Oct 28;131(42):15160–15169. doi: 10.1021/ja9034768

Table 4.

Comparison of the ¹³C chemical shifts of the retinal C5 and C8 carbons along with the T₁ relaxation measurement for the C18 methyl group in wild-type rhodopsin, Meta II and retinal model compounds

Compound	Temperature (K)	¹³C5 (ppm)	¹³C8 (ppm)	¹³C18 (T₁) (sec)

6-s-trans^B	296	134.6-144.8	131.6-133.4	25.6-31.7
6-s-cis^B	296	126.7-129.4	138.2-140.6	0.41-3.69
6-s-trans retinoic acid (monoclinic)	190	136.5	131.3	12.3
6-s-cis retinoic acid (triclinic)	190	129.6	139.7	0.14
Rhodopsin	190	131.0	139.3	0.34
Meta II	190	126.0	139.6	0.56

Data from Harbison et al.¹⁷