Descriptors of ProtFP for 20 coded amino acids.
AA	Abbr.	PC1 a	PC2	PC3	PC4	PC5	PC6	PC7	PC8
Ala	A	-0.10	-4.94	-2.13	1.70	-0.39	1.06	-1.39	0.97
Arg	R	-2.79	6.60	1.21	2.07	1.67	0.76	0.00	0.32
Asn	N	-4.88	0.81	0.14	-0.14	1.23	-0.65	1.02	-1.94
Asp	D	-6.61	0.94	-3.04	-4.58	0.48	-1.31	0.10	0.94
Cys	C	4.62	-3.54	1.50	-1.26	3.27	-0.34	-0.47	-0.23
Gln	Q	-3.95	2.88	-0.83	0.52	0.90	0.55	-0.08	0.64
Glu	E	-5.10	2.20	-3.59	-2.26	-2.14	1.35	-0.45	-1.31
Gly	G	-5.70	-9.72	4.18	-1.35	-0.31	2.91	0.32	-0.11
His	H	0.17	2.14	1.20	0.71	1.16	-0.38	-1.85	-2.79
Ile	I	6.58	-1.73	-2.49	1.09	-0.34	-0.28	1.97	-0.92
Leu	L	5.76	-1.33	-1.71	0.63	-1.70	0.71	-0.05	-0.51
Lys	K	-4.99	5.00	0.70	3.00	-1.23	1.41	0.19	0.87
Met	M	5.11	0.19	-1.02	0.15	0.13	-0.30	-2.95	0.50
Phe	F	6.76	0.88	0.89	-1.12	-0.49	-0.55	-0.87	1.05
Pro	P	-3.82	-2.31	3.45	1.00	-3.22	-3.54	-0.36	-0.30
Ser	S	-3.82	-2.31	3.45	1.00	-3.22	-3.54	-0.36	-0.30
Thr	T	-2.00	-1.77	-0.70	1.02	1.06	-1.02	0.74	1.65
Trp	W	7.33	4.55	2.77	-2.41	-1.08	1.04	0.23	0.59
Tyr	Y	3.14	3.59	2.45	-1.27	-0.06	-0.29	1.99	0.30
Val	V	5.04	-2.90	-2.29	1.38	0.06	0.08	1.79	-0.38
a The 8 principal component scores based on a PCA analysis of 58 amino acids properties explain 92% of the variances. For these predominant components, the first one is related to hydrophobicity and the second one is related to the size of amino acids.
References [1] G. J. van Westen, R. F. Swier, J. K. Wegner, A. P. Ijzerman, H. W. van Vlijmen, A. Bender, Benchmarking of protein descriptor sets in proteochemometric modeling (part 1): comparative study of 13 amino acid descriptor sets, J. Cheminformatics, 5 (2013) 41.