Table I.

Library designs

Library	Design			Diversity
	BC	DE	FG	BC	DE	FG
WT	DAPAVTVRY	GSKST	GRGDSPASSK	1	1	1
NNB	X6–9Y	X4–7	X5,6,8,10	5 × 1011	1 × 109	1 × 1013
YS	(S|Y)7–10	gsX0,1,3st	(S|Y)6,7,8,10	2 × 103	1 × 109	1 × 103

WT, wild-type sequence; X, any amino acid; S|Y, either serine or tyrosine; g, 50% glycine, 50% any other amino acid (analogous for s, t); subscripts refer to the number of amino acids.