Table 1. Fluorescent Proteins Tested.

Protein	λex	λem	QY	EC	Brightness	Reference
Blue Fluorescent Proteins:
mTagBFP	402	457	0.63	52000	32.8	[27]
mTagBFP2	399	454	0.64	50600	32.4	[28]
Green Fluorescent Proteins:
EGFP	488	507	0.6	56000	33.6	[29], [30]
Clover	505	515	0.76	111000	84.4	[16]
Emerald	487	509	0.68	57500	39.1	[15]
GFPγ						[31]
MaxGFP						Amaxa
Superfolder GFP	485	510	0.65	83300	54.1	[32]
mWasabi	493	509	0.80	70000	56.0	[13]
Red Fluorescent Proteins:
mCherry	587	610	0.22	72000	15.8	[33]
mApple	568	592	0.49	75000	36.8	[20]
mKate2	588	633	0.4	62500	25.0	[21]
mKO2	551	565	0.62	63800	39.6	[34]
mRuby	558	605	0.35	112000	39.2	[35]
mRuby2	559	600	0.38	113000	42.9	[16]
TagRFP-T	555	584	0.41	81000	33.2	[20]
Others:
TagRFP657	611	657	0.10	3400	0.34	[36]
mKeima	440	620	0.24	14400	3.5	[37]
LSS-mKate2	460	605	0.17	26000	4.4	[38]

λex and λem are the peak excitation and emission wavelengths of the fluorescent protein, respectively. QY is the quantum yield and EC the extinction coefficient in M⁻¹ cm⁻¹. Brightness is the product of QY and EC, divided by 1000. Data was taken from the literature and is not available for GFPγ or MaxGFP.