TABLE 24-2 The Standard Amino Acids Functiona Name Symbol Abbreviation Structure Point side chain is nonpolar,H or alkyl glycine G Gly HN-CH一COOH none 6.0 面 alaninc Ala H.N-CH-COOH alkyl group 6.0 H valine Val HN-CH-COOH alkyl group 6.0 leucine Leu H,N一CH一COOH alkyl group 6.0 CH,一CH-CH, CH, isoleucine H,N-CH-COOH alkyl group 6.0 CH,-CH一CH.CH1 phenylalanine Phe H,N-CH-COOH aromatic group 5.5 CH,- proline Pro HN-CH一COOH rigid cyclie structure 6.3 H. CH, CH. side chain contains an-OH serine Ser H,N-CH一COOH hydroxyl group 57 CH-OH threonine Thr H,N-CH-COOH hydroxyl group 5.6 HO-CH一CH Copyright 2010 Pearson Prentice Hall,Inc. Chapter 24 8 Chapter 24 8