Table 12.4.

Amino Acid Abbreviations

Amino Acid	Three-Letter Abbreviation	One-Letter Abbrev.	Systematic Name
alanine	Ala	A	2-aminopropanoic acid
arginine	Arg	R	2-amino-5-guanidinopentanoic acid
asparagine	Asn	N	2-amino-3-carbamoylpropanoic acid
aspartic acid	Asp	D	2-aminobutanedioic acid
cysteine	Cys	C	2-amino-3-mercaptopropanoic acid
glutamic acid	Glu	E	2-aminopentanedioic acid
glutamine	Gin	Q	2-amino-4-carbamoylbutanoic acid
glycine	Gly	G	aminoethanoic acid
histidine	His	H	2-amino-3-(1H-imidazol-4-yl)propanoic acid
isoleucine	Ile	I	2-amino-3-methylpentanoic acid
leucine	Leu	L	2-amino-4-methylpentanoic acid
lysine	Lys	K	2,6-diaminohexanoic acid
methionine	Met	M	2-amino-4-(methylthio)butanoic acid
phenylalanine	Phe	F	2-amino-3-phenylpropanoic acid
proline	Pro	P	Pyrrolidine-2-carboxylic acid
serine	Ser	S	2-amino-3-hydroxypropanoic acid
threonine	Thr	T	2-amino-3-hydroxybutanoic acid
tryptophan	Trp	W	2-amino-3-(1H-indol-3-yl)propanoic acid
tyrosine	Tyr	Y	2-amino-3-(4-hydroxyphenyl)propanoic acid
valine	Val	V	2-amino-3-methylbutanoic acid