The following table lists common one- and three- letter abbreviations for amino acid residues that you enter in the peptide Formula box in the Ranges dialog box.

Common one- and three-letter abbreviations for amino acid residues

One letter

Name

Formula

Three letter

A

Alanine

C3H7NO2

Ala

C

Cysteine

C3H7NO2S

Cys

D

Aspartic acid

C4H7NO4

Asp

E

Glutamic acid

C5H9NO4

Glu

F

Phenylalanine

C9H11NO2

Phe

G

Glycine

C2H5NO2

Gly

H

Histidine

C6H9N3O2

His

I

Isoleucine

C6H13NO2

Ile

K

Lysine

C6H14N2O2

Lys

L

Leucine

C6H13NO2

Leu

M

Methionine

C5H11NO2S

Met

N

Asparagine

C4H8N2O3

Asn

P

Proline

C5H9NO2

Pro

Q

Glutamine

C5H10N2O3

Gln

R

Arginine

C6H14N4O2

Arg

S

Serine

C3H7NO3

Ser

T

Threonine

C4H9NO3

Thr

V

Valine

C5H11NO2

Val

W

Tryptophan

C11H12N2O2

Trp

Y

Tyrosine

C9H11NO3

Tyr