Table 1.

20 proteinogenic amino acid classification differentiated by their side chain according to their polarity [10].

Symbol	Category	1-letter code
P−	polar	D, E, Y
N	neutral	C, G, N, Q, S, T
P+	basic hydrophilic	H, K, R
NP	non polar residues	A, F, I, L, M, P, V, W