Table 1. Characteristics of intrinsic and chromophore fluorescence of sfGFP in native and unfolded states.

Parameter	sfGFP in native state	sfGFP in unfolded state (in presence of 2.5 M GTC)
	Intrinsic fluorescence
λmax, nm (λex 297 nm)	322 (+ a shoulder at 335 nm)	350
Parameter A (λex 297 nm)	3.9	0.48
r (λex 297 nm, λem 365 nm)	0.19	0.09
τ, ns (λex 297 nm, λem 335 nm)	0.67	2.46
	Chromophore fluorescence
λmax, nm (λex 365 nm)	512	–
I max, %	100	0
τ, ns (λex 365 nm, λem 510 nm)	3.32	–
τ, ns (λex 490 nm, λem 510 nm)	2.49	–
	Quenching by acrylamide
k q of Trp 57 at λem 335 nm, 109 M−1 s−1	0.91±0.08	6.1±0.4
k q of Cro at λex 365 nm, 109 M−1 s−1	0.06±0.01	–
k q of Cro at λex 490 nm, 109 M−1 s−1	0.04±0.01	–