List of amino acids and their abbreviations Nonpolar Amino Acids (hydrophobic) Polar (hydrophilic) amino acid three letter code single letter code Gly alanine A serine valine Val threonine Thr cysteine C C euc ine isoleuc ine lle tyrosine methionine Met asparagine phenylalanine Phe F glutamine GIn tryptophan Ir proline Pro Electrically Charged(positive Electrically Charged (negative and and hydrophilic) hydrophilic aspartic acid D arginine Arg R glutamic acid histidine Yellow amino acids contain sulfur. Blue amino acids can be phosphorylatedList of Amino Acids and Their Abbreviations amino acid three letter code single letter code glycine Gly G alanine Ala A valine Val V leucine Leu L isoleucine Ile I methionine Met M phenylalanine Phe F tryptophan Trp W proline Pro P Polar (hydrophilic) serine Ser S threonine Thr T cysteine Cys C tyrosine Tyr Y asparagine Asn N glutamine Gln Q Electrically Charged (negative and hydrophilic) aspartic acid Asp D glutamic acid Glu E Electrically Charged (positive and hydrophilic) lysine Lys K arginine Arg R histidine His H Nonpolar Amino Acids (hydrophobic) Yellow amino acids contain sulfur. Blue amino acids can be phosphorylated