TABLE 6.

Amino acid residues around (putative) SPase I cleavage sites^a

−3		−2		−1		+1
Residue	Frequency	Residue	Frequency	Residue	Frequency	Residue	Frequency
A	0.71	S	0.22	A	1.00	A	0.45
V	0.18	K, E	0.25			Q	0.15
T, I, S, G, W	0.11	H, Y	0.19			E	0.10
		Q, G	0.10			K, S, V	0.18
		F, L, A, D, N	0.22			F, N, L, D, T	0.12
		W, P	0.02

^aThe frequency of a particular amino acid at the indicated positions around SPase I cleavage sites in signal peptides of 54 identified extracellular (Table 1) (4, 6, 129), and 4 cell wall-located (Table 3) (6) (pre)proteins with (putative) SPase I cleavage sites. Residues with similar frequencies of appearance at a certain position are grouped.