Amino Acids Table

Here is a list of the standard one-letter amino acid codes and their three-letter equivalents. The synonymous codons and their depiction in the IUB codes are shown. You should recognize that the codons following semicolons ( are not sufficiently specific to define a single amino acid even though they represent the best possible backtranslation into the IUB codes!

Symbol 3-letter Code Amino-acid Codons
A Ala Alanine GCT,GCC,GCA,GCG
B Asp,Asn Aspartic, Asparagine GAT,GAC,AAT,AAC
C Cys Cysteine TGT,TGC
D Asp Aspartic GAT,GAC
E Glu Glutamic GAA,GAG
F Phe Phenylalanine TTT,TTC
G Gly Glycine GGT,GGC,GGA,GGG
H His Histidine CAT,CAC
I Ile Isoleucine ATT,ATC,ATA
K Lys Lysine AAA,AAG
L Leu Leucine TTG,TTA,CTT,CTC,CTA,CTG
M Met Methionine ATG
N Asn Asparagine AAT,AAC
P Pro Proline CCT,CCC,CCA,CCG
Q Gln Glutamine CAA,CAG
R Arg Arginine CGT,CGC,CGA,CGG,AGA,AGG
S Ser Serine TCT,TCC,TCA,TCG,AGT,AGC
T Thr Threonine ACT,ACC,ACA,ACG
V Val Valine GTT,GTC,GTA,GTG
W Trp Tryptophan TGG
X Xxx Unknown
Y Tyr Tyrosine TAT,TAC
Z Glu,Gln Glutamic, Glutamine GAA,GAG,CAA,CAG
* End Terminator TAA,TAG,TGA

Standard Genetic Code

U C A G
U UUU Phe F
UUC Phe F
UUA Leu L
UUG Leu L
UCU Ser S
UCC Ser S
UCA Ser S
UCG Ser S UAU Tyr Y
UAC Tyr Y
UAA Stop
UAG Stop
UGU Cys C
UGC Cys C
UGA Stop
UGG Trp W

C
CUU Leu L
CUC Leu L
CUA Leu L
CUG Leu L

CCU Pro P
CCC Pro P
CCA Pro P
CCG Pro P

CAU His H
CAC His H
CAA Gln Q
CAG Gln Q

CGU Arg R
CGC Arg R
CGA Arg R
CGG Arg R

A
AUU Ile I
AUC Ile I
AUA Ile I
AUG Met M

ACU Thr T
ACC Thr T
ACA Thr T
ACG Thr T

AAU Asn N
AAC Asn N
AAA Lys K
AAG Lys K

AGU Ser S
AGC Ser S
AGA Arg R
AGG Arg R

G
GUU Val V
GUC Val V
GUA Val V
GUG Val V

GCU ALA A
GCC ALA A
GCA ALA A
GCG ALA A

GAU Asp D
GAC Asp D
GAA Glu E
GAG Glu E

GGU Gly G
GGC Gly G
GGA Gly G
GGG Gly G