EBI Groups Thornton Group MACiE Documentation

X Numbers in MACiE

X-Number	Compound	Notes
X00001	Halo-carboxylamino-acetic acid
X00002	Ribosyl group	CHEBI:26565
X00003	Amino-halo-acetic acid
X00004	DNA strand	Obsolete. Transferred to C00039
X00005	3'-OH-oligonucleotide	Obsolete. Transferred to X00016
X00006	5'-phospho-oligonucleotide	Obsolete. Transferred to X00015
X00007	Hypochlorous acid	CHEBI:24757
X00008	Nitrocefin	A specific type of beta lactam, no longer included in MACiE replaces by the generic beta lactam C01866.
X00009	Substituted beta-amino acid of nitrocefin	A specific type of substituted beta-amino acid, no longer included in MACiE replaces by the generic substituted beta-amino acid C03806.
X00010	Benylpenicillin	A specific type of beta lactam, no longer included in MACiE replaces by the generic beta lactam C01866.
X00011	Phenylacetylamino-(4,5,5-trimetyl-thiazolidin-2-yl)-acetic acid	A specific type of substituted beta-amino acid, no longer included in MACiE replaces by the generic substituted beta-amino acid C03806.
X00012	2-chloropropionate
X00013	2-hydroxypropionate	Alternative name: lactate. CHEBI:16651. Obsolete. Transferred to C00186.
X00014	DNA phosphate linkage	Obsolete. Transferred to C00039
X00015	DNA 5'-phosphate
X00016	DNA 3'-hydroxyl
X00017	1,4-alpha-D-glucan chain	CHEBI:15444. Obsolete. Transferred to C00718
X00018	DNA	Obsolete. Transferred to C00039
X00019	2-oxo-4-hexenedioate	Obsolete. Transferred to C03453: 5-Oxohex-2-enedioate. Also represented by CHEBI:16967
X00020	5-oxohex-3-enedioate
X00021	Carbamoyl group	CHEBI:23004
X00022	Hydronium ion	CHEBI:29412
X00023	Tryptophan tryptophylquinone (TTQ)	TTQ is a cofactor made up of two tryptophan residues which are usually part of the protein chain, and is considered a cofactor, thus it is now more correct to name it as TTQ, rather than the X number.
X00024	Acetyl group	CHEBI:22190
X00025	Methyl group	CHEBI:32875
X00026	4a((R)-Hydroxy-6(S)-methyl-tetrahydropterin	CHEBI:15374
X00027	Quinoid dihydrobiopterin	CHEBI:20680. Obsolete. Transferred to C00268
X00028	Phosphoribosyl group
X00029	PLP-Lysine	The covalent complext between PLP and Lysine that is found in the ground state of many PLP-dependent enzymes.
X00030	PMP	Pyridoxamine phosphate (CHEBI:18335). The non-enzyme bound intermediate found in PLP-dependent enzyme reactions. Obsolete. Transferred to C00647
X00031	(R) Glutathione-methylgluoxal thiohemiacetal	The enzyme only works on the hemithioacetal intermediate, which is formed by the spontaneous reaction between methylglyoxal and glutathione.
X00032	4-(methoxymethyl)phenol
X00033	Molybdo-monopyranopterin Mo(VI)	The molybdenum complex of the molybdopterin prosthetic group (ligand). CHEBI:21437
X00034	Molybdo-monopyranopterin Mo(VI) with Cu(I)	The molybdenum complex of the molybdopterin prosthetic group (ligand). CHEBI:21437. In this case the cofactor has an extra copper (I) centre associated with it.
X00035	4'-imino TPP
X00036	4'-imino-C2-alpha-carbanion 2-(1-hydroxyethyl) TPP	Obsolete. This is a reaction intermediate that is not common, and as such is no longer assigned an X number.
X00037	[CuSMo(=O)OH] cluster Mo(VI)	Obsolete.
X00038	[CuSMo(=O)OH] cluster Mo(IV)	Obsolete.
X00039	Flavin adenine dinucleotide hydroperoxide	A common intermediate in the oxidation of reduced FAD. This X number should only be used when the FAD is not a cofactor, otherwise the three letter code and number associated with the PDB file should be used.
X00040	alpha-keto acid	Obsolete. Transferred to C00161
X00041	Flavin adenine dinucleotide semiquinone	The semi-quinone form of FAD. This X number should only be used when the FAD is not a cofactor, otherwise the three letter code and number associated with the PDB file should be used.
X00042	Flavin mononucleotide semiquinone	The semi-quinone form of FMN. This X number should only be used when the FMN is not a cofactor, otherwise the three letter code and number associated with the PDB file should be used.
X00043	Adenosinyl radical	This is the result of the homolytic fission of a Co-C bond in cobalamin (vitamin B12).
X00044	Adenosinyl
X00045	Flavin adenine dinucleotide H^-	This compound number represents two resonance forms.
X00046	Flavin monoucleotide H	This compound number represents two resonance forms.
X00047	Flavin mononucleotide hydroperoxide	A common intermediate in the oxidation of reduced FMN. This X number should only be used when the FMN is not a cofactor, otherwise the three letter code and number associated with the PDB file should be used.
X00048	Enolpyruvate	This is in intermediate formed in 4.1.1.49 (M0051)
X00049	protein-phosphocysteine	Obsolete.
X00050	Oxidised cytochrome c
X00051	Single electron reduced acceptor	R^-
X00052	Two electron reduced acceptor	R^2-. Obsolete. Transferred to C00030
X00053	Single electron donor	R^-
X00054	Two electron donor	R^2-
X00055	4-hydroxybenzyl alcohol
X00056	Adrenodoxin	Fe³⁺
X00057	Reduced adrenodoxin	Fe²⁺
X00058	Protonated flavin adenine dinucleotide semiquinone	A common reaction intermediate in FAD containing reactions
X00059	protonated flavin mononucleotide semiquinone	A common reaction intermediate in FMN containing reactions
X00060	6-Hydroxymethyl-7,8-dihydropterin	Obsolete now C01300.
X00061	7,8-dihydro-6-(diphosphooxymethyl)pterin	Obsolete now C04807.
X00062	Hydride	CHEBI:29239
X00063	Nucleoside 5'-phosphate
X00064	DNA 3'-phosphate
X00065	DNA 5'-hydroxyl
X00066	Cyclobutane pyrimidine dimer
X00067	Cyclobutane pyrimidine dimer 5'-phosphate
X00068	DNA 3'-α,β-unsatured aldehyde
X00069	RNA 3'-hydroxyl
X00070	RNA 5'-phosphate
X00071	RNA 3'-phosphate
X00072	RNA 5'-hydroxyl
X00073	C-terminus of a protein	The C-terminal amino acid residue.
X00074	L-aminoacyl-L-proline
X00075	β-Aspartyl-dipeptide
X00076	Polygalacturonate	Obsolete. Replaced by C00470: poly(1,4-alpha-D-galacturonate).
X00077	Oligosaccharides with 4-deoxy-α-D-galact-4-enuronosyl at its non-reducing end.	Obsolete. Replaced by C06118 (4-(4-deoxy-α-D-gluc-4-enuronosyl)-D-galacturonate).
X00078	Apurinic or apyrimidinic site in DNA	No longer in MACiE as a more precise compound has been utilised. Thus X00078 has been replaced by: X00115 (DNA 8-oxoguanine) in M0185.
X00079	DNA with 3-terminal trans-α,β-unsaturated sugar
X00080	DNA 5'-phosphate	Obsolete. It already exist as X00015
X00081	[4Fe4S] cluster	Iron-Sulphur cluster cofactor. Where possible, this should now be named from the HET group name in the PDB file.
X00082	Reduced Fe4S4 cluster	Iron-Sulphur cluster cofactor. Where possible, this should now be named from the HET group name in the PDB file.
X00083	Ferredoxin - two electron reduced
X00084	Thiamin diphosphate (TPP) - negatively charged	This is a cofactor, and as such, the HET group code from the PDB should be used where possible.
X00085	Fe(III)2S2 cluster	Iron-Sulphur cluster cofactor. Where possible, this should now be named from the HET group name in the PDB file.
X00086	Fe(III)Fe(II)S2 cluster	Iron-Sulphur cluster cofactor. Where possible, this should now be named from the HET group name in the PDB file.
X00087	4a-hydroxytetrahydrobiopterin
X00088	Molybdo-dipyranopterin Mo(VI)	This is a cofactor. Where possible, this should now be named from the HET group name in the PDB file.
X00089	Single electron oxidised pseudoazurin
X00090	Alkyl peroxide
X00091	Phosphate monoester	Obsolete. Transferred to C01153: orthophosphoric monoester
X00092	(ADP-D-ribosyl) (n+1)-acceptor
X00093	Cobalamin(II)	The R group represents a protein ligand, for example in M0062, R is His610
X00094	Electron-Transferring Flavoprotein one electron reduced
X00095	B2 Heme (oxidised)
X00096	B2 Heme (reduced)
X00097	[dihydrolipoyllysine-residue acetyltransferase] lipoyllysine	Obsolete. Transferred to C15972
X00098	[dihydrolipoyllysine-residue acetyltransferase] S-acetyldihydrolipoyllysine	Obsolete. Transferred to C16255
X00099	Hydroporphinoid nickel complex coenzyme F430	Obsolete. Replaced by C05777. This is a cofactor. Where possible, this should now be named from the HET group name in the PDB file.
X00100	Fe-only hydrogenase H cluster
X00101	Ferrocytochrome C3 - one electron reduced
X00102	Ferrocytochrome C3 - two electron reduced
X00103	Ferrocytochrome C3 - three electron reduced
X00104	semidehydroascorbate
X00105	Ferredoxin - one electron reduced
X00106	Monooxygen dianion	O^2-
X00107	Hemoprotein - oxidised
X00108	Hemoprotein - two electron reduced
X00109	Hemoprotein - one electron reduced
X00110	Protein with two disulfide bridges
X00111	Protein with two disulfide bridges	Although effectively the same as X00110, this has the disulphide bridges in a different configuration to X00110.
X00112	Chalcone
X00113	Flavanone
X00114	Putidaredoxin - one electron reduced
X00115	DNA 8-oxoguanine
X00116	8-oxoguanine
X00117	Peptidoglycan (1,4-beta-linkage between N-acetylmuramic acid and N-acetyl-D-glucosamin).
X00118	Ubisemiquinone
X00119	N-terminus of a protein
X00120	Doubly cleaved double-stranded DNA
X00121	Phenol derivative
X00122	Phenol derivative radical
X00123	Acylated lysine protein
X00124	2'-O-acetyl ADP-ribose
X00125	L-aspartate beta semi aldehyde hydrate
X00126	(4S)-4-hydroxy-2,3,4,5-tetrahydro-(2S)-dipicolinic acid
X00127	5-epi-aristolochine
X00128	mercury dithiol
X00129	dithiol
X00130	reduced cytochrome b6f
X00131	oxidised photosystem I
X00132	oxidised cytochrome b6f
X00133	reduced photosystem I
X00134	phosphorylated serine protein
X00135	D-alanyl-(R)-lactate
X00136	S-methyl phosphotriester
X00137	aryl alcohol	At some point this X number had KEDD ID C01891.
X00138	alpha,beta cyclic unsaturated ketone
X00139	alpha,beta cyclic ketone
X00140	3-methyladenine DNA
X00141	DNA minus adenine base
X00143	Protein (n-1), N-terminus
X00144	Protein (n-2), C-terminus
X00145	(1,4-alpha-D-glucosyl)n-1
X00146	DNA with two adjacent pyrimidine bases
X00147
X00148	The aspartate group of CheY.	A chemoreceptor protein involved in signal transduction in chemotaxis.
X00149	The phosphorylated aspartate group of CheY.	The chemical modification is essential for the role of CheY as a chemoreceptor protein required for chemotaxis signal transduction.