Table B.1. pkar and pl values for the 20 common amino acids. The amino acids in bold type are ionisable. Amino Acid Alanine Arginine Asparagine Aspartic acid Cysteine Glutamine Glutamic acid Glycine Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Proline Serine Threonine Tryptophan Tyrosine Valine Abbreviation Ala Arg Asn Asp Cys Gln Glu Gly His lle Leu Lys Met Phe Pro Ser Thr Trp Tyr Val Single letter abbreviation A R N D C Q E G H | L K M F P S T W Y V Linear formula of R-group CH3 HN=C(NH2)-NH-(CH2)3 HN-CO-CH2 HOOC-CH2 HS-CH H2N-CO-(CH2)2 HOOC-(CH2)2 H NH-CH=N-CH=C-CH2 CH3-CH2-CH(CH3) (CH3)2-CH-CH HN-(CH)4 CH3-S-(CH)2 Ph-CH, (CH)3 HO-CH2 CH3-CH(OH) Ph-NH-CH=C-CH2 HO-Ph-CH, (CH3)2-CH pKar values c. In which direction would peptide M move in an electric field at pH 9.5? 12.48 3.65 8.18 4.25 6.00 10.53 pl 6.01 10.76 5.41 2.77 5.07 5.65 3.22 5.97 7.59 6.02 5.98 9.74 5.74 5.48 6.48 5.68 5.87 5.89 5.66 5.97 b. Calculate the pl of peptide M and indicate what charge the peptide would have when pH=pl. (4 minutes) (2 minutes)