Noncanonical Amino Acids

Unnatural amino acid library

A source-linked library of individual noncanonical amino acids, including the complete 60-residue HighPlay2 design alphabet.

80 unique database-mapped entries 60 HighPlay2 residues + 20 reference entries

Scope

TPDB 3D structure viewers are intended for standard-residue peptide models. This library records individual noncanonical amino acid building blocks as 2D molecules rather than predicting modified peptide 3D structures.

Data provenance

The 60-residue selection and study labels come from HighPlay2 Supplementary Table S1 and Supplementary Data 1. CCD identity, formula, formula weight, parent mapping, and 2D depictions are linked to the RCSB PDB Chemical Component Dictionary. The 20 additional reference entries use PubChem identity records, formulae, formula weights, source links, and 2D depictions. Commercial availability is reported by the study and is not independently verified by TPDB.

Browse by type

Noncanonical amino acid classes

Showing all 80 entries

D-amino acids

5 entries
2D structure of D-Alanine
D-Ala

D-Alanine

D-丙氨酸

The D stereoisomer of alanine; D-residue substitution is used to reduce protease susceptibility.

Formula
C3H7NO2
Formula weight
89.09 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 71080
2D structure of D-Arginine
D-Arg

D-Arginine

D-精氨酸

A guanidinium-bearing arginine residue with D stereochemistry for cationic peptide design.

Formula
C6H14N4O2
Formula weight
174.20 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 71070
2D structure of D-Lysine
D-Lys

D-Lysine

D-赖氨酸

A lysine residue with D stereochemistry that retains a basic, positively charged side chain.

Formula
C6H14N2O2
Formula weight
146.19 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 57449
2D structure of D-Phenylalanine
D-Phe

D-Phenylalanine

D-苯丙氨酸

An aromatic phenylalanine residue with D stereochemistry, used in stability-oriented peptide design.

Formula
C9H11NO2
Formula weight
165.19 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 71567
2D structure of D-Tryptophan
D-Trp

D-Tryptophan

D-色氨酸

An indole-bearing tryptophan residue with D stereochemistry for membrane-interacting peptide design.

Formula
C11H12N2O2
Formula weight
204.22 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 9060

Conformationally restricted

8 entries
2D structure of Phenylglycine
CCD 004
HighPlay2

Phenylglycine

苯甘氨酸

A noncanonical residue with altered backbone or side-chain geometry for peptide design.

Formula
C8H9NO2
Formula weight
151.163 Da
Parent residue
Not assigned
Sources
RCSB CCD 004 HighPlay2
2D structure of 2-aminoisobutyric acid
CCD AIB Aib
HighPlay2

2-aminoisobutyric acid

2-氨基异丁酸

An achiral alpha,alpha-disubstituted amino acid associated with restricted, helix-favoring conformations.

Formula
C4H9NO2
Formula weight
103.120 Da
Parent residue
ALA
Sources
RCSB CCD AIB PubChem CID 6119 HighPlay2
2D structure of Cyclohexylglycine
CCD CHG
HighPlay2

Cyclohexylglycine

环己基甘氨酸

A noncanonical residue with altered backbone or side-chain geometry for peptide design.

Formula
C8H15NO2
Formula weight
157.210 Da
Parent residue
Not assigned
Sources
RCSB CCD CHG HighPlay2
2D structure of 5-oxoproline (pyroglutamic acid)
CCD PCA
HighPlay2

5-oxoproline (pyroglutamic acid)

5-氧代脯氨酸（焦谷氨酸）

A noncanonical residue with altered backbone or side-chain geometry for peptide design.

Formula
C5H7NO3
Formula weight
129.114 Da
Parent residue
GLN
Sources
RCSB CCD PCA HighPlay2
2D structure of tert-Leucine (3-methylvaline)
CCD TBG
HighPlay2

tert-Leucine (3-methylvaline)

叔亮氨酸（3-甲基缬氨酸）

A noncanonical residue with altered backbone or side-chain geometry for peptide design.

Formula
C6H13NO2
Formula weight
131.173 Da
Parent residue
VAL
Sources
RCSB CCD TBG HighPlay2
2D structure of 1-Aminocyclopropane-1-carboxylic acid
Ac3c

1-Aminocyclopropane-1-carboxylic acid

1-氨基环丙烷-1-羧酸

An achiral cyclopropane alpha-amino acid that fixes the alpha-carbon substituents in a compact geometry.

Formula
C4H7NO2
Formula weight
101.10 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 535
2D structure of L-Pipecolic acid
L-Pip

L-Pipecolic acid

L-哌啶-2-羧酸

A six-membered cyclic imino acid and ring-expanded homolog of proline.

Formula
C6H11NO2
Formula weight
129.16 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 439227
2D structure of L-Tetrahydroisoquinoline-3-carboxylic acid
L-Tic

L-Tetrahydroisoquinoline-3-carboxylic acid

L-1,2,3,4-四氢异喹啉-3-羧酸

A rigid cyclic aromatic amino acid used to restrict peptide backbone and side-chain geometry.

Formula
C10H11NO2
Formula weight
177.20 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 2733226

Side-chain analogs

18 entries
2D structure of O-methyl-L-tyrosine
CCD 0A1
HighPlay2

O-methyl-L-tyrosine

O-甲基-L-酪氨酸

A noncanonical analog of tyrosine included in the HighPlay2 design alphabet.

Formula
C10H13NO3
Formula weight
195.215 Da
Parent residue
TYR
Sources
RCSB CCD 0A1 HighPlay2
2D structure of 5-hydroxy-L-tryptophan
CCD 4PQ
HighPlay2

5-hydroxy-L-tryptophan

5-羟基-L-色氨酸

A noncanonical analog of tryptophan included in the HighPlay2 design alphabet.

Formula
C11H12N2O3
Formula weight
220.225 Da
Parent residue
TRP
Sources
RCSB CCD 4PQ HighPlay2
2D structure of 2-aminobutyric acid
CCD ABA L-Abu
HighPlay2

2-aminobutyric acid

2-氨基丁酸

A small aliphatic amino acid with a side chain one carbon longer than alanine.

Formula
C4H9NO2
Formula weight
103.120 Da
Parent residue
ALA
Sources
RCSB CCD ABA PubChem CID 80283 HighPlay2
2D structure of beta-cyclohexylalanine
CCD ALC L-Cha
HighPlay2

beta-cyclohexylalanine

β-环己基丙氨酸

A hydrophobic phenylalanine analog containing a saturated cyclohexyl side chain.

Formula
C9H17NO2
Formula weight
171.237 Da
Parent residue
ALA
Sources
RCSB CCD ALC PubChem CID 712421 HighPlay2
2D structure of Citrulline
CCD CIR L-Cit
HighPlay2

Citrulline

瓜氨酸

A neutral ureido amino acid structurally related to arginine.

Formula
C6H13N3O3
Formula weight
175.186 Da
Parent residue
ARG
Sources
RCSB CCD CIR PubChem CID 9750 HighPlay2
2D structure of 3-hydroxy-L-tyrosine (L-DOPA)
CCD DAH
HighPlay2

3-hydroxy-L-tyrosine (L-DOPA)

3-羟基-L-酪氨酸（左旋多巴）

A noncanonical analog of tyrosine included in the HighPlay2 design alphabet.

Formula
C9H11NO4
Formula weight
197.188 Da
Parent residue
TYR
Sources
RCSB CCD DAH HighPlay2
2D structure of 2-amino-4-(ethylthio)butyric acid
CCD ESC
HighPlay2

2-amino-4-(ethylthio)butyric acid

2-氨基-4-(乙硫基)丁酸

A noncanonical analog of methionine included in the HighPlay2 design alphabet.

Formula
C6H13NO2S
Formula weight
163.238 Da
Parent residue
MET
Sources
RCSB CCD ESC HighPlay2
2D structure of 4-amino-L-phenylalanine
CCD HOX
HighPlay2

4-amino-L-phenylalanine

4-氨基-L-苯丙氨酸

A noncanonical analog of phenylalanine included in the HighPlay2 design alphabet.

Formula
C9H12N2O2
Formula weight
180.204 Da
Parent residue
PHE
Sources
RCSB CCD HOX HighPlay2
2D structure of Homophenylalanine
CCD HPE L-hPhe
HighPlay2

Homophenylalanine

高苯丙氨酸

A phenylalanine homolog with one additional methylene group before the phenyl ring.

Formula
C10H13NO2
Formula weight
179.216 Da
Parent residue
PHE
Sources
RCSB CCD HPE PubChem CID 2724505 HighPlay2
2D structure of Homoserine
CCD HSE
HighPlay2

Homoserine

高丝氨酸

A noncanonical analog of serine included in the HighPlay2 design alphabet.

Formula
C4H9NO3
Formula weight
119.119 Da
Parent residue
SER
Sources
RCSB CCD HSE HighPlay2
2D structure of Selenomethionine
CCD MSE
HighPlay2

Selenomethionine

硒代蛋氨酸

A noncanonical analog of methionine included in the HighPlay2 design alphabet.

Formula
C5H11NO2Se
Formula weight
196.106 Da
Parent residue
MET
Sources
RCSB CCD MSE HighPlay2
2D structure of Norleucine
CCD NLE L-Nle
HighPlay2

Norleucine

正亮氨酸

A straight-chain, sulfur-free amino acid commonly used as a methionine analog.

Formula
C6H13NO2
Formula weight
131.173 Da
Parent residue
LEU
Sources
RCSB CCD NLE PubChem CID 21236 HighPlay2
2D structure of Norvaline
CCD NVA
HighPlay2

Norvaline

正缬氨酸

A noncanonical analog of valine included in the HighPlay2 design alphabet.

Formula
C5H11NO2
Formula weight
117.146 Da
Parent residue
VAL
Sources
RCSB CCD NVA HighPlay2
2D structure of Ornithine
CCD ORN L-Orn
HighPlay2

Ornithine

鸟氨酸

A basic non-proteinogenic amino acid whose side chain is one methylene shorter than lysine.

Formula
C5H12N2O2
Formula weight
132.161 Da
Parent residue
ALA
Sources
RCSB CCD ORN PubChem CID 6262 HighPlay2
2D structure of 4-nitro-L-phenylalanine
CCD PPN
HighPlay2

4-nitro-L-phenylalanine

4-硝基-L-苯丙氨酸

A noncanonical analog of phenylalanine included in the HighPlay2 design alphabet.

Formula
C9H10N2O4
Formula weight
210.187 Da
Parent residue
PHE
Sources
RCSB CCD PPN HighPlay2
2D structure of L-alpha-aminoadipic acid
CCD UN1
HighPlay2

L-alpha-aminoadipic acid

L-α-氨基己二酸

A noncanonical amino acid included in the HighPlay2 design alphabet.

Formula
C6H11NO4
Formula weight
161.156 Da
Parent residue
Not assigned
Sources
RCSB CCD UN1 HighPlay2
2D structure of 1-Naphthyl-L-alanine
1-Nal

1-Naphthyl-L-alanine

1-萘基-L-丙氨酸

A bulky aromatic alanine analog containing a 1-naphthyl side chain.

Formula
C13H13NO2
Formula weight
215.25 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 2724883
2D structure of L-Homoarginine
L-hArg

L-Homoarginine

L-高精氨酸

An arginine homolog with one additional methylene group in the side chain.

Formula
C7H16N4O2
Formula weight
188.23 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 9085

Beta-amino acids

4 entries
2D structure of (3S)-Beta-leucine
beta-Leu

(3S)-Beta-leucine

(3S)-β-亮氨酸

A branched-chain beta-amino acid containing an isopropyl side chain.

Formula
C6H13NO2
Formula weight
131.17 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 439734
2D structure of (S)-3-Amino-4-phenylbutanoic acid
beta-hPhe

(S)-3-Amino-4-phenylbutanoic acid

(S)-3-氨基-4-苯基丁酸

An aromatic beta-amino acid containing a benzyl substituent on the amino-bearing carbon.

Formula
C10H13NO2
Formula weight
179.22 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 2761537
2D structure of (S)-3-Aminobutyric acid
beta-hAla

(S)-3-Aminobutyric acid

(S)-3-氨基丁酸

A chiral beta-amino acid with a methyl substituent on the amino-bearing beta carbon.

Formula
C4H9NO2
Formula weight
103.12 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 2761506
2D structure of Beta-alanine
beta-Ala

Beta-alanine

β-丙氨酸

An achiral beta-amino acid with the amino group on the beta carbon, extending the peptide backbone.

Formula
C3H7NO2
Formula weight
89.09 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 239

N-methyl amino acids

17 entries
2D structure of N-methylserine
CCD 5JP
HighPlay2

N-methylserine

N-甲基丝氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C4H9NO3
Formula weight
119.119 Da
Parent residue
SER
Sources
RCSB CCD 5JP HighPlay2
2D structure of N-methyltryptophan
CCD E9M
HighPlay2

N-methyltryptophan

N-甲基色氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C12H14N2O2
Formula weight
218.252 Da
Parent residue
TRP
Sources
RCSB CCD E9M HighPlay2
2D structure of N-methylglutamic acid
CCD EME
HighPlay2

N-methylglutamic acid

N-甲基谷氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C6H11NO4
Formula weight
161.156 Da
Parent residue
GLU
Sources
RCSB CCD EME HighPlay2
2D structure of N-methylglutamine
CCD GNC
HighPlay2

N-methylglutamine

N-甲基谷氨酰胺

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C6H12N2O3
Formula weight
160.171 Da
Parent residue
GLN
Sources
RCSB CCD GNC HighPlay2
2D structure of N-methylisoleucine
CCD IML
HighPlay2

N-methylisoleucine

N-甲基异亮氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C7H15NO2
Formula weight
145.199 Da
Parent residue
ILE
Sources
RCSB CCD IML HighPlay2
2D structure of N-methylalanine
CCD MAA N-Me-L-Ala
HighPlay2

N-methylalanine

N-甲基丙氨酸

An N-methylated alanine that changes backbone hydrogen-bonding and conformational behavior.

Formula
C4H9NO2
Formula weight
103.120 Da
Parent residue
ALA
Sources
RCSB CCD MAA PubChem CID 5288725 HighPlay2
2D structure of N-methylphenylalanine
CCD MEA N-Me-L-Phe
HighPlay2

N-methylphenylalanine

N-甲基苯丙氨酸

An aromatic N-methyl amino acid used to alter backbone hydrogen bonding and conformation.

Formula
C10H13NO2
Formula weight
179.216 Da
Parent residue
PHE
Sources
RCSB CCD MEA PubChem CID 6951135 HighPlay2
2D structure of N-methylasparagine
CCD MEN
HighPlay2

N-methylasparagine

N-甲基天冬酰胺

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C5H10N2O3
Formula weight
146.144 Da
Parent residue
ASN
Sources
RCSB CCD MEN HighPlay2
2D structure of N-methylleucine
CCD MLE N-Me-L-Leu
HighPlay2

N-methylleucine

N-甲基亮氨酸

A hydrophobic N-methylated leucine derivative with altered backbone hydrogen-bonding capacity.

Formula
C7H15NO2
Formula weight
145.199 Da
Parent residue
LEU
Sources
RCSB CCD MLE PubChem CID 2777993 HighPlay2
2D structure of N-methylmethionine
CCD MME
HighPlay2

N-methylmethionine

N-甲基蛋氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C6H13NO2S
Formula weight
163.238 Da
Parent residue
MET
Sources
RCSB CCD MME HighPlay2
2D structure of N-methylvaline
CCD MVA
HighPlay2

N-methylvaline

N-甲基缬氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C6H13NO2
Formula weight
131.173 Da
Parent residue
VAL
Sources
RCSB CCD MVA HighPlay2
2D structure of N-methylcysteine
CCD NCY
HighPlay2

N-methylcysteine

N-甲基半胱氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C4H9NO2S
Formula weight
135.185 Da
Parent residue
Not assigned
Sources
RCSB CCD NCY HighPlay2
2D structure of N-methyllysine
CCD NMK
HighPlay2

N-methyllysine

N-甲基赖氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C7H17N2O2
Formula weight
161.222 Da
Parent residue
Not assigned
Sources
RCSB CCD NMK HighPlay2
2D structure of N-methylthreonine
CCD NZC
HighPlay2

N-methylthreonine

N-甲基苏氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C5H11NO3
Formula weight
133.146 Da
Parent residue
THR
Sources
RCSB CCD NZC HighPlay2
2D structure of N-methylglycine (sarcosine)
CCD SAR Sar
HighPlay2

N-methylglycine (sarcosine)

N-甲基甘氨酸（肌氨酸）

N-Methylglycine, the simplest achiral N-methyl amino acid building block.

Formula
C3H7NO2
Formula weight
89.093 Da
Parent residue
GLY
Sources
RCSB CCD SAR PubChem CID 1088 HighPlay2
2D structure of N-methylaspartic acid
CCD SOQ
HighPlay2

N-methylaspartic acid

N-甲基天冬氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C5H9NO4
Formula weight
147.129 Da
Parent residue
Not assigned
Sources
RCSB CCD SOQ HighPlay2
2D structure of N-methyltyrosine
CCD YNM
HighPlay2

N-methyltyrosine

N-甲基酪氨酸

An N-methylated amino acid represented explicitly in the HighPlay2 residue alphabet.

Formula
C10H13NO3
Formula weight
195.215 Da
Parent residue
TYR
Sources
RCSB CCD YNM HighPlay2

Halogenated amino acids

8 entries
2D structure of 2-chloro-L-phenylalanine
CCD 2L5
HighPlay2

2-chloro-L-phenylalanine

2-氯-L-苯丙氨酸

A halogenated amino acid analog represented explicitly in the HighPlay2 residue alphabet.

Formula
C9H10ClNO2
Formula weight
199.634 Da
Parent residue
Not assigned
Sources
RCSB CCD 2L5 HighPlay2
2D structure of Trifluoroalanine
CCD FLA
HighPlay2

Trifluoroalanine

三氟丙氨酸

A halogenated amino acid analog represented explicitly in the HighPlay2 residue alphabet.

Formula
C3H4F3NO2
Formula weight
143.065 Da
Parent residue
ALA
Sources
RCSB CCD FLA HighPlay2
2D structure of 5-fluoro-L-tryptophan
CCD FTR
HighPlay2

5-fluoro-L-tryptophan

5-氟-L-色氨酸

A halogenated amino acid analog represented explicitly in the HighPlay2 residue alphabet.

Formula
C11H11FN2O2
Formula weight
222.216 Da
Parent residue
TRP
Sources
RCSB CCD FTR HighPlay2
2D structure of 3-fluoro-L-phenylalanine
CCD N0A
HighPlay2

3-fluoro-L-phenylalanine

3-氟-L-苯丙氨酸

A halogenated amino acid analog represented explicitly in the HighPlay2 residue alphabet.

Formula
C9H10FNO2
Formula weight
183.180 Da
Parent residue
PHE
Sources
RCSB CCD N0A HighPlay2
2D structure of 4-fluoro-L-phenylalanine
CCD PFF 4-F-L-Phe
HighPlay2

4-fluoro-L-phenylalanine

4-氟-L-苯丙氨酸

A para-fluorinated phenylalanine analog with modified aromatic electronic properties.

Formula
C9H10FNO2
Formula weight
183.180 Da
Parent residue
PHE
Sources
RCSB CCD PFF PubChem CID 716312 HighPlay2
2D structure of 4-iodo-L-phenylalanine
CCD PHI 4-I-L-Phe
HighPlay2

4-iodo-L-phenylalanine

4-碘-L-苯丙氨酸

A para-iodinated phenylalanine analog with an iodine-substituted aromatic ring.

Formula
C9H10INO2
Formula weight
291.086 Da
Parent residue
PHE
Sources
RCSB CCD PHI PubChem CID 134497 HighPlay2
2D structure of 4-Bromo-L-phenylalanine
4-Br-L-Phe

4-Bromo-L-phenylalanine

4-溴-L-苯丙氨酸

A para-brominated phenylalanine analog with a larger halogen substituent.

Formula
C9H10BrNO2
Formula weight
244.08 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 671214
2D structure of 4-Chloro-L-phenylalanine
4-Cl-L-Phe

4-Chloro-L-phenylalanine

4-氯-L-苯丙氨酸

A para-chlorinated phenylalanine analog with a halogenated aromatic side chain.

Formula
C9H10ClNO2
Formula weight
199.63 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 736190

Bioorthogonal amino acids

4 entries
2D structure of Propargylglycine
CCD F9D L-Pra
HighPlay2

Propargylglycine

炔丙基甘氨酸

A terminal-alkyne amino acid used as a handle for click-chemistry conjugation.

Formula
C5H7NO2
Formula weight
113.115 Da
Parent residue
Not assigned
Sources
RCSB CCD F9D PubChem CID 168091 HighPlay2
2D structure of L-Azidohomoalanine
Aha

L-Azidohomoalanine

L-叠氮高丙氨酸

An azide-bearing methionine analog used as a bioorthogonal labeling handle.

Formula
C4H8N4O2
Formula weight
144.13 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 147480
2D structure of L-Homopropargylglycine
Hpg

L-Homopropargylglycine

L-高炔丙基甘氨酸

A methionine analog bearing a terminal alkyne for bioorthogonal labeling and conjugation.

Formula
C6H9NO2
Formula weight
127.14 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 11344028
2D structure of p-Azido-L-phenylalanine
pAzF

p-Azido-L-phenylalanine

4-叠氮-L-苯丙氨酸

A phenylalanine analog bearing a para-azide group as a bioorthogonal reaction handle.

Formula
C9H10N4O2
Formula weight
206.20 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 3080772

Modified residues

16 entries
2D structure of S-methyl-D-cysteine
CCD 060
HighPlay2

S-methyl-D-cysteine

S-甲基-D-半胱氨酸

CCD identity note HighPlay2 labels the L isomer; CCD 060 is defined as D-peptide linking. Study label: S-methyl-L-cysteine
Formula
C4H9NO2S
Formula weight
135.185 Da
Parent residue
Not assigned
Sources
RCSB CCD 060 HighPlay2
2D structure of N,N-dimethylarginine (SDMA)
CCD 2MR
HighPlay2

N,N-dimethylarginine (SDMA)

对称二甲基精氨酸（SDMA）

A chemically modified residue represented by a defined PDB CCD component.

Formula
C8H18N4O2
Formula weight
202.254 Da
Parent residue
ARG
Sources
RCSB CCD 2MR HighPlay2
2D structure of N6-acetyl-L-lysine
CCD ALY AcK
HighPlay2

N6-acetyl-L-lysine

N6-乙酰-L-赖氨酸

An L-lysine residue acetylated at the side-chain amino group, representing lysine acetylation.

Formula
C8H16N2O3
Formula weight
188.224 Da
Parent residue
LYS
Sources
RCSB CCD ALY PubChem CID 92832 HighPlay2
2D structure of S-carboxymethyl-D-cysteine
CCD CCJ
HighPlay2

S-carboxymethyl-D-cysteine

S-羧甲基-D-半胱氨酸

CCD identity note HighPlay2 labels the L isomer; CCD CCJ is defined as D-peptide linking. Study label: S-carboxymethyl-L-cysteine
Formula
C5H9NO4S
Formula weight
179.194 Da
Parent residue
Not assigned
Sources
RCSB CCD CCJ HighPlay2
2D structure of Asymmetric dimethylarginine (ADMA)
CCD DA2
HighPlay2

Asymmetric dimethylarginine (ADMA)

非对称二甲基精氨酸（ADMA）

A chemically modified residue represented by a defined PDB CCD component.

Formula
C8H18N4O2
Formula weight
202.254 Da
Parent residue
ARG
Sources
RCSB CCD DA2 HighPlay2
2D structure of 1-methyl-L-histidine
CCD HIC
HighPlay2

1-methyl-L-histidine

1-甲基-L-组氨酸

A chemically modified residue represented by a defined PDB CCD component.

Formula
C7H11N3O2
Formula weight
169.181 Da
Parent residue
HIS
Sources
RCSB CCD HIC HighPlay2
2D structure of 4-hydroxyproline
CCD HYP L-Hyp
HighPlay2

4-hydroxyproline

4-羟基脯氨酸

A 4-hydroxylated proline residue found prominently in collagen-derived sequences.

Formula
C5H9NO3
Formula weight
131.130 Da
Parent residue
PRO
Sources
RCSB CCD HYP PubChem CID 5810 HighPlay2
2D structure of Methionine sulfoxide
CCD MHO
HighPlay2

Methionine sulfoxide

蛋氨酸亚砜

A chemically modified residue represented by a defined PDB CCD component.

Formula
C5H11NO3S
Formula weight
165.211 Da
Parent residue
MET
Sources
RCSB CCD MHO HighPlay2
2D structure of 3-methyl-L-histidine
CCD MHS
HighPlay2

3-methyl-L-histidine

3-甲基-L-组氨酸

A chemically modified residue represented by a defined PDB CCD component.

Formula
C7H11N3O2
Formula weight
169.181 Da
Parent residue
HIS
Sources
RCSB CCD MHS HighPlay2
2D structure of 3-sulfo-L-alanine (cysteic acid)
CCD OCS
HighPlay2

3-sulfo-L-alanine (cysteic acid)

3-磺基-L-丙氨酸（半胱氨酸磺酸）

A chemically modified residue represented by a defined PDB CCD component.

Formula
C3H7NO5S
Formula weight
169.156 Da
Parent residue
CYS
Sources
RCSB CCD OCS HighPlay2
2D structure of Methionine sulfone
CCD OMT
HighPlay2

Methionine sulfone

蛋氨酸砜

A chemically modified residue represented by a defined PDB CCD component.

Formula
C5H11NO4S
Formula weight
181.210 Da
Parent residue
MET
Sources
RCSB CCD OMT HighPlay2
2D structure of N6-propionyl-L-lysine
CCD PRK
HighPlay2

N6-propionyl-L-lysine

N6-丙酰-L-赖氨酸

A chemically modified residue represented by a defined PDB CCD component.

Formula
C9H18N2O3
Formula weight
202.251 Da
Parent residue
LYS
Sources
RCSB CCD PRK HighPlay2
2D structure of Phosphoserine
CCD SEP pSer
HighPlay2

Phosphoserine

磷酸丝氨酸

The phosphorylated form of L-serine and a common post-translationally modified residue.

Formula
C3H8NO6P
Formula weight
185.072 Da
Parent residue
SER
Sources
RCSB CCD SEP PubChem CID 68841 HighPlay2
2D structure of S-(2-aminoethyl)-L-cysteine
CCD SLZ
HighPlay2

S-(2-aminoethyl)-L-cysteine

S-(2-氨基乙基)-L-半胱氨酸

A chemically modified residue represented by a defined PDB CCD component.

Formula
C5H12N2O2S
Formula weight
164.226 Da
Parent residue
LYS
Sources
RCSB CCD SLZ HighPlay2
2D structure of Phosphothreonine
CCD TPO
HighPlay2

Phosphothreonine

磷酸苏氨酸

A chemically modified residue represented by a defined PDB CCD component.

Formula
C4H10NO6P
Formula weight
199.099 Da
Parent residue
THR
Sources
RCSB CCD TPO HighPlay2
2D structure of O-Sulfo-L-tyrosine
sTyr

O-Sulfo-L-tyrosine

O-磺基-L-酪氨酸

An L-tyrosine residue sulfated at the phenolic oxygen, representing tyrosine sulfation.

Formula
C9H11NO6S
Formula weight
261.25 Da
Parent residue
Not provided by PubChem
Sources
PubChem CID 514186