Table 1. Residue substitutions in ECFP-derived proteins compared with avGFP.

Roman type, avGFP (Aquorea victoria GFP) wild-type residue; bold type, residues engineered to improve the photophysical properties (the list of substitutions is not comprehensive).

	ECFP†	Cerulean‡	mCerulean2§	mCerulean3§	mTurquoise§	mTurquoise-GL¶	mTurquoise2¶
Quantum yield††	0.36	0.48	0.60	0.87	0.84	0.82	0.93
Residue
64	L	L	L	L	L	L	L
65	T	T	T	S	S	S	S
66	W	W	W	W	W	W	W
72	S	A	A	A	A	A	A
145	Y	A	A	A	Y	Y	Y
146	I	I	I	I	I	I	F
147	S	S	H	H	S	S	S
148	H	D	G	G	D	G	D
153	T	T	T	T	T	T	T
163	A	A	A	A	A	A	A
166	K	K	G	G	K	K	K
167	I	I	L	L	I	I	I
168	R	R	N	N	R	R	R
169	H	H	C	C	H	H	H
175	S	S	S	S	G	G	G
224	V	V	V	V	V	L	V

^†Heim Tsien (1996 ▶).

^‡Rizzo et al. (2004 ▶).

^§Markwardt et al. (2011 ▶).

^¶Goedhart et al. (2010 ▶).

^††Quantum yield measurements, as reported from the references cited, were generally performed at ambient temperature under solution conditions.