Any L-alpha-amino acid which is not a member of the group of 23 proteinogenic amino acids.
| Member | Definition | Role |
|---|
| (S)-2-amino-6-boronohexanoic acid | L-Norleucine substituted at C-6 with a borono group. | (S)-2-amino-6-boronohexanoic acid |
| (S)-ATPA | A non-proteinogenic L-alpha-amino acid that is L-alanine in which one of the methyl hydrogens is replaced by a 5-tert-butyl-3-hydroxy-isooxazol-4-yl group. | (S)-ATPA |
| 1-methylhistidine | A L-histidine derivative in which the methyl group is at N(tele)-position. | N(tele)-methyl-L-histidine zwitterion; N(tele)-methyl-L-histidine |
| 2-amino-4-phosphonobutyric acid | A non-proteinogenc L-alpha-amino acid that is L-alpha-aminobutyric acid in which one of the hydrogens of the terminal methyl group has been replaced by a dihydroxy(oxido)-lambda(5)-phosphanyl group. It is a potent and selective agonist for the group III metabotropic glutamate receptors (mGluR4/6/7/8). | (2S)-2-amino-4-phosphonobutanoic acid |
| 2-formyl-5-(hydroxymethyl)pyrrole-1-norleucine | An N-substituted pyrraline formed via Maillard reaction of L-lysine with glucose. | 1-(L-norleucin-6-yl)pyrraline |
| 2,5-dihydrophenylalanine | | 2,5-dihydrophenyl-L-alanine |
| 3-chloro-L-tyrosine | A chloroamino acid comprising a tyrosine core with a chloro- substituent ortho to the phenolic hydroxy group. | 3-chloro-L-tyrosine zwitterion; 3-chloro-L-tyrosine |
| 3-methoxytyrosine | A L-tyrosine derivative that is the 3-methoxy derivative of L-dopa. | 3-O-methyldopa zwitterion; 3-O-methyldopa |
| 3-methylhistidine | A L-histidine derivative that is L-histidine substituted by a methyl group at position 3 on the imidazole ring. | N(pros)-methyl-L-histidine zwitterion; N(pros)-methyl-L-histidine |
| 3-methylhistidine | | N(pros)-methyl-L-histidine zwitterion; N(pros)-methyl-L-histidine |
| 3-tyrosine | A hydroxyphenylalanine that is L-phenylalanine with a substituent hydroxy group at position 3. | L-m-tyrosine zwitterion; L-m-tyrosine |
| 3,5-dichlorotyrosine | A chloroamino acid that is L-tyrosine carrying chloro- substituents at positions C-3 and C-5 of the benzyl group. | 3,5-dichloro-L-tyrosine |
| 3,5-dihydroxyphenylglycine | A glycine derivative that is L-alpha-phenylglycine substituted at positions 3 and 5 on the phenyl ring by hydroxy groups. | (S)-3,5-dihydroxyphenylglycine zwitterion; (S)-3,5-dihydroxyphenylglycine |
| 4-chlorothreonine | A chloroamino acid that is L-threonine in which one of the hydrogens of the terminal methyl group has been replaced by a chlorine. | 4-chloro-L-threonine |
| 4-fluorophenyl-L-alanine | A L-phenylalanine derivative that is L-phenylalanine in which the hydrogen at position 4 on the benzene ring is replaced by a fluoro group. | 4-fluorophenyl-L-alanine |
| 4-fluorothreonine | | 4-fluoro-L-threonine zwitterion; 4-fluoro-L-threonine |
| 4-ketoproline | The L-enantiomer of 4-oxoproline. | 4-oxo-L-proline zwitterion; 4-oxo-L-proline |
| 5-fluorowillardiine | An alanine derivative that is L-alanine bearing a 5-fluorouracil-1-yl substituent at position 3. A more potent and selective AMPA receptor agonist (at hGluR1 and hGluR2) than AMPA itself (Ki = 14.7, 25.1, and 1820 nM for hGluR1, hGluR2 and hGluR5 respectively). | 3-(5-fluorouracil-1-yl)-L-alanine |
| 5-hydroxytryptophan | The L-enantiomer of 5-hydroxytryptophan. | 5-hydroxy-L-tryptophan zwitterion; 5-hydroxy-L-tryptophan |
| 6-bromotryptophan | A bromoamino acid that is L-tryptophan in which the hydrogen at position 6 of the indole ring is substituted by bromine. | L-6'-bromotryptophan zwitterion; L-6'-bromotryptophan |
| 6-chlorotryptophan | A non-proteinogenic L-alpha-amino acid that is L-tryptophan in which the hydrogen at position 6 on the indole ring has been replaced by a chlorine. | 6-chloro-L-tryptophan zwitterion; 6-chloro-L-tryptophan |
| 7-chlorotryptophan | An L-tryptophan derivative having a chloro substituent at the 7-position. | 7-chloro-L-tryptophan zwitterion; 7-chloro-L-tryptophan |
| acivicin | An L-alpha-amino acid that is L-alanine in which the methyl group is replaced by a (5S)-3-chloro-4,5-dihydro-1,2-oxazol-5-yl group. A glutamine analogue antimetabolite, it interferes with glutamate metabolism and several glutamate-dependent synthetic enzymes. It is obtained as a fermentation product of Streptomyces sviceus bacteria. | acivicin |
| agaritine | | agaritine zwitterion; agaritine |
| albizziin | | L-Albizziine |
| allysine | An optically active form of allysine having L-configuration. | L-allysine zwitterion; L-allysine |
| anticapsin | An alanine derivative that is L-alanine bearing a 5-oxo-7-oxabicyclo[4.1.0]hept-2-yl substituent at position 3. | anticapsin zwitterion; anticapsin |
| azaserine | A carboxylic ester resulting from the formal condensation of the carboxy group of diazoacetic acid with the alcoholic hydroxy group of L-serine. An antibiotic produced by a Streptomyces species. | azaserine |
| beta-aspartyl phosphate | The 4-phospho derivative of L-aspartic acid. | 4-phospho-L-aspartic acid |
| beta-n-methylamino-l-alanine | A non-proteinogenic L-alpha-amino acid that is L-alanine in which one of the methyl hydrogens is replaced by a methylamino group. A non-proteinogenic amino acid produced by cyanobacteria, it is a neurotoxin that has been postulated as a possible cause of neurodegenerative disorders of aging such as Alzheimer's disease, amyotrophic lateral sclerosis, and the amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS-PDC) syndrome of Guam. | L-BMAA |
| biocytin | A monocarboxylic acid amide that results from the formal condensation of the carboxylic acid group of biotin with the N(6)-amino group of L-lysine. | biocytin zwitterion; biocytin |
| c(alpha)-formylglycine | The L-enantiomer of 3-oxoalanine. | L-3-oxoalanine zwitterion; L-3-oxoalanine |
| canaline | A non-proteinogenic L-alpha-amino acid that is L-homoserine in which the hydroxy group at position 4 is substituted by an aminooxy group. It has been isolated from legumes and plays an essential role in lugume chemical defense against insects. | L-canaline zwitterion; L-canaline |
| canavanine | A non-proteinogenic L-alpha-amino acid that is L-homoserine substituted at oxygen with a guanidino (carbamimidamido) group. Although structurally related to L-arginine, it is non-proteinogenic. | L-canavanine zwitterion; L-canavanine |
| carbocysteine | An L-cysteine thioether that is L-cysteine in which the hydrogen of the thiol group has been replaced by a carboxymethyl group. | S-carboxymethyl-L-cysteine |
| cefoxitin | A non-proteinogenic L-amino acid that is N-acetyl-alpha-D-galactosamine linked via an alpha glycosidic bond to the O at position 3 of L-serine. | O-(N-acetyl-alpha-D-galactosaminyl)-L-serine |
| cilastatin | The thioether resulting from the formal oxidative coupling of the thiol group of L-cysteine with the 7-position of (2Z)-2-({[(1S)-2,2-dimethylcyclopropyl]carbonyl}amino)hept-2-enoic acid. It is an inhibitor of dehydropeptidase I (membrane dipeptidase, 3.4.13.19), an enzyme found in the brush border of renal tubes and responsible for degrading the antibiotic imipenem. Cilastatin is therefore administered (as the sodium salt) with imipenem to prolong the antibacterial effect of the latter by preventing its renal metabolism to inactive and potentially nephrotoxic products. Cilastatin also acts as a leukotriene D4 dipeptidase inhibitor, preventing the metabolism of leukotriene D4 to leukotriene E4. | cilastatin |
| coprine | A non-proteinogenic L-alpha-amino acid that is L-glutamine in which one of the hydrogens attached to the amide nitrogen is replaced by a 1-hydroxycyclopropyl group. Found in the ink-cap mushroom, Coprinus atramentarius, it causes an unpleasant hypersensitivity to alcohol (the 'disulfiram effect'). | coprine |
| cysteinesulfenic acid | A cysteine derivative consisting of L-cysteine carrying an S-hydroxy-substituent. | S-hydroxy-L-cysteine |
| cystine | The L-enantiomer of the sulfur-containing amino acid cystine. | L-cystine zwitterion; L-cystine |
| dansyllysine | An L-lysine derivative with a dansyl group at the N(6)-position. | N(6)-dansyl-L-lysine |
| delta-n-methylarginine | A non-proteinogenic L-alpha-amino acid that is L-arginine substituted by a methyl group at N(5)-position. | N(5)-methyl-L-arginine |
| deoxyhypusine | An L-lysine derivative in which the N(6) of the lysine is substituted with a 4-aminobutyl group. | deoxyhypusine |
| diazooxonorleucine | A non-proteinogenic L-alpha-amino acid that is L-norleucine which is substituted at position 5 by an oxo group and at position 6 by a diazo group. It is as inhibitor of various glutamine-utilising enzymes. | 6-diazo-5-oxo-L-norleucine zwitterion; 6-diazo-5-oxo-L-norleucine |
| diiodotyrosine | A diiodotyrosine that is L-tyrosine carrying iodo-substituents at positions C-3 and C-5 of the benzyl group. It is an intermediate in the thyroid hormone synthesis. | 3,5-diiodo-L-tyrosine |
| djenkolic acid | A dithioacetal consisting of two molecules of L-cysteine joined via their sulfanyl groups to methylene. | L-djenkolic acid |
| domoic acid | An L-proline derivative that is L-proline substituted by a carboxymethyl group at position 3 and a 6-carboxyhepta-2,4-dien-2-yl group at position 4. It is produced by the diatomic algal Pseudo-nitzschia. It is an analogue of kainic acid and a neurotoxin which causes amnesic shellfish poisoning (ASP). | domoic acid |
| epsilon n-dimethyllysine | An L-lysine derivative comprising L-lysine having two methyl substituents attached to the side-chain amino group. | N(6),N(6)-dimethyl-L-lysine |
| epsilon-n-methyllysine | An L-lysine derivative that is L-lysine in which one of the hydrogens attached to N(6) is substituted by a methyl group. | N(6)-methyl-L-lysine |
| felinine | A cysteine thioether that is the S-(4-hydroxy-2-methylbutan-2-yl) derivative of L-cysteine. It is a major component of the urine of the domestic cat. | felinine zwitterion; felinine |
| furanomycin | A non-proteinogenic L-alpha-amino acid that is L-alanine in which the methyl group is replaced by a (2R,5S)-5-methyl-2,5-dihydrofuran-2-yl moiety. | furanomycin |
| glycerophosphoserine | A L-serine derivative consisting of L-serine having a 1-glycerophospho group attached to the side-chain hydroxy function. | glycerol 1-phosphoserine |
| homoarginine | An L-lysine derivative that is the L-enantiomer of homoarginine. | L-homoarginine |
| homocitrulline | A L-lysine derivative that is L-lysine having a carbamoyl group at the N(6)-position. It is found in individuals with urea cycle disorders. | L-homocitrulline zwitterion; L-homocitrulline |
| hydroxythreonine | A hydroxy-amino acid consisting of L-threonine having a hydroxy substituent at the 4-position. | 4-hydroxy-L-threonine zwitterion; 4-hydroxy-L-threonine |
| i-677 | An L-alpha-amino acid that is L-serine in which the hydroxy group at position 3 is converted to the corresponding 2-aminoethyl ether. An antimetabolic antibiotic obtained from Streptomyces reseoviridofuscus. | O-(2-aminoethyl)-L-serine |
| indospicine | An alpha-amino acid that is 2,7-diaminoheptanoic acid substituted by a imino group at position 7 (the 2S stereoisomer). | L-indospicine |
| kainic acid | | kainic acid |
| kynurenine | A kynurenine that has L configuration. | L-kynurenine zwitterion; L-kynurenine |
| leukotriene e4 | A leukotriene that is (7E,9E,11Z,14Z)-icosa-7,9,11,14-tetraenoic acid substituted by a hydroxy group at position 5 (5S) and an L-cystein-S-yl group at position 6 (6R). | leukotriene E4 |
| levodopa | An optically active form of dopa having L-configuration. Used to treat the stiffness, tremors, spasms, and poor muscle control of Parkinson's disease | L-dopa zwitterion; L-dopa |
| lysine tyrosylquinone | An L-lysine derivative in which one of the amino hydrogens at N(6)-amino is substituted by a 6-[(2S)-2-amino-2-carboxyethyl]-3,4-dioxocyclohexa-1,5-dien-1-yl group. | 5'-(N(6)-L-lysine)-L-tyrosylquinone |
| mannopine | A hexitol derivative that is D-mannitol in which the hydroxy group at position 1 is replaced by the alpha-amino group of L-glutamine. It is produced in crown gall tumours induced in a wide range of dicotyledenous plants by Agrobacterium tumefaciens. | mannopine |
| melphalan | A phenylalanine derivative comprising L-phenylalanine having [bis(2-chloroethyl)amino group at the 4-position on the phenyl ring. | melphalan |
| methionine sulfone | An L-methionine derivative in which the sulfur has been oxidised to the corresponding sulfone. | L-methionine sulfone; methionine sulfone zwitterion |
| methionine sulfoximine | A methionine sulfoximine in which the amino group has S-stereochemistry. | L-methionine sulfoximine zwitterion; L-methionine sulfoximine |
| methyl-3-tyrosine | A tyrosine derivative that is L-tyrosine in which the hydrogen at position 3 on the phenyl ring is replaced by a methyl group. | 3-methyl-L-tyrosine zwitterion; 3-methyl-L-tyrosine |
| methyldopa | A derivative of L-tyrosine having a methyl group at the alpha-position and an additional hydroxy group at the 3-position on the phenyl ring. | alpha-methyl-L-dopa |
| metyrosine | An L-tyrosine derivative that consists of L-tyrosine bearing an additional methyl substituent at position 2. An inhibitor of the enzyme tyrosine 3-monooxygenase, and consequently of the synthesis of catecholamines. It is used to control the symptoms of excessive sympathetic stimulation in patients with pheochromocytoma. | alpha-methyl-L-tyrosine |
| mimosine | An L-alpha-amino acid that is propionic acid substituted by an amino group at position 2 and a 3-hydroxy-4-oxopyridin-1(4H)-yl group at position 3 (the 2S-stereoisomer). It a non-protein plant amino acid isolated from Mimosa pudica. | L-mimosine zwitterion; L-mimosine |
| monoiodotyrosine | The monoiodotyrosine that is L-tyrosine carrying an iodo-substituent at position C-3 of the benzyl group. | 3-iodo-L-tyrosine zwitterion; 3-iodo-L-tyrosine |
| n,n-dimethylarginine | A L-arginine derivative having two methyl groups both attached to the primary amino moiety of the guanidino group. | N(omega),N(omega)-dimethyl-L-arginine |
| n'-formylkynurenine | | N-formyl-L-kynurenine zwitterion; N-formyl-L-kynurenine |
| n(5)-hydroxy-l-arginine | | N(delta)-hydroxy-L-arginine |
| n(6)-(1-carboxyethyl)lysine | A L-lysine derivative formed during the reaction between methylglyoxal and protein. CEL is a homologue of N(epsilon)-(carboxymethyl)lysine (CML), an advanced glycation end-product that is formed on reaction of glyoxal or glycolaldehyde with protein and on oxidative cleavage of fructoselysine, the Amadori adduct formed on glycation of protein by glucose. | N(6)-(1-carboxyethyl)-L-lysine |
| n(6)-(1-iminoethyl)lysine | An L-lysine derivative that is L-lysine in which one of the hydrogens attached to N(6) is substituted by an acetimidoyl group | N(6)-acetimidoyl-L-lysine |
| n(6)-carboxymethyllysine | An L-lysine derivative with a carboxymethyl substituent at the N(6)-position. | N(6)-carboxymethyl-L-lysine |
| nitroarginine | An L-arginine derivative that is L-arginine in which the terminal nitrogen of the guanidyl group is replaced by a nitro group. | N(gamma)-nitro-L-arginine |
| norleucine | A non-proteinogenic L-alpha-amino acid comprising hexanoic acid carrying an amino group at C-2. It does not occur naturally. | L-2-aminohexanoic acid zwitterion; L-norleucine |
| o-methyl threonine | An L-threonine derivative that is L-threonine with a methyl group replacing the hydrogen on the hydroxy side chain. | O-methyl-L-threonine |
| o-methylserine | A serine derivative that is L-serine with a methyl group replacing the hydrogen on the hydroxy side chain. | O-methylserine |
| omega-n-methylarginine | A L-arginine derivative with a N(omega)-methyl substituent. | (2S)-2-amino-5-[[amino(methylimino)methyl]amino]pentanoic acid; N(omega)-methyl-L-arginine zwitterion; N(omega)-methyl-L-arginine |
| ornithine | An optically active form of ornithine having L-configuration. | L-ornithine |
| ovothiol a | A L-histidine derivative that is L-histidine substituted at positions N3 and C5 on the imidazole ring by methyl and mercapto groups respectively. | ovothiol A zwitterion; ovothiol A |
| pentosidine | An imidazopyridine having norleucine and ornithine residues attached via their side-chains at the 4- and 2-positions respectively. | pentosidine |
| phospho-l-arginine | An arginine derivative that is L-arginine substituted by a phosphono group at N(omega)-position. | N(omega)-phospho-L-arginine |
| phosphothreonine | A L-threonine derivative phosphorylated at the side-chain hydroxy function. | O-phospho-L-threonine |
| phosphotyrosine | A non-proteinogenic L-alpha-amino acid that is L-tyrosine phosphorylated at the phenolic hydroxy group. | O(4)-phospho-L-tyrosine |
| pyrrolidonecarboxylic acid | An optically active form of 5-oxoproline having L-configuration. | 5-oxo-L-proline |
| s-2-aminoethyl cysteine | A cysteine derivative that is the S-(2-aminoethyl) analogue of L-cysteine; reported to have cytotoxic effects. | L-thialysine |
| s-methylthiocitrulline | An L-arginine derivative in which the guanidino NH2 group of L-arginine is replaced by a methylsufanyl group. | S-methyl-L-thiocitrulline |
| selenomethylselenocysteine | An L-alpha-amino acid compound having methylselanylmethyl as the side-chain. | Se-methyl-L-selenocysteine zwitterion; Se-methyl-L-selenocysteine |
| serine o-sulfate | A non-proteinogenic L-alpha-amino acid that is the O-sulfo derivative of L-serine. | L-serine O-sulfate |
| symmetric dimethylarginine | A L-arginine derivative having two methyl groups at the N(omega)- and N'(omega)-positions | N(omega),N'(omega)-dimethyl-L-arginine zwitterion; N(omega),N'(omega)-dimethyl-L-arginine |
| tabtoxinine beta-lactam | | tabtoxinine beta-lactam |
| thyroxine | The L-enantiomer of thyroxine. | L-thyroxine zwitterion; L-thyroxine |
| trifluoromethionine | An L-alpha-amino acid, methionine, with the S-methyl group trifluoro-substituted. | trifluoro-L-methionine |
| vinylglycine | A non-proteinogenic L-alpha-amino acid with a structure in which a vinyl group is bonded to the alpha-carbon of glycine. | L-vinylglycine zwitterion; L-vinylglycine |
| willardiine | The 3-(uracil-1-yl) derivative of L-alanine. | 3-(uracil-1-yl)-L-alanine zwitterion; 3-(uracil-1-yl)-L-alanine |