Table 1.

Substrate sequences cleaved selectively by POP or by FAP.^a

Cleaved only by POP				Cleaved only by FAP
Xaa	Yaa	Zaa	Fold Change	Xaa	Yaa	Zaa	Fold Change
P	D/E	I/L	2.41	P	A/V	D/E	3.45
P	P	F/Y	2.30	P	A/V	K/R	10.61
F/Y	P	I/L	2.13	P	D/E	A/V	4.42
I/L	P	I/L	2.67	P	D/E	K/R	4.72
K/R	P	I/L	2.30	P	D/E	N/Q	2.38
K/R	P	F/Y	2.33	P	F/Y	F/Y	11.45
K/R	P	S/T	2.04	P	I/L	D/E	4.44
S/T	P	S/T	2.34	P	I/L	F/Y	5.38
A/V	K/R	P	2.11	P	I/L	K/R	9.21
F/Y	A/V	P	4.19	P	K/R	D/E	6.46
F/Y	K/R	P	2.31	P	K/R	F/Y	8.17
F/Y	S/T	P	2.39	P	K/R	K/R	10.62
I/L	N/Q	P	2.39	P	K/R	N/Q	16.64
I/L	S/T	P	3.55	P	N/Q	F/Y	9.59
K/R	A/V	P	2.10
S/T	F/Y	P	2.03

^aSelective IQFP motifs were identified by screening a combinatorial substrate library. For each sequence, the endpoint fluorescence fold change value is shown. IQFP wells were considered to be cleaved if fold change values greater than 2 were observed.