2.02012-05-31 14:32:29 -06002015-06-03 17:19:30 -0600ECMDB20194M2MDB001040SirohemeSiroheme belongs to the class of Precorrins. These are intermediates formed by methylation at one or more of the four rings prior to the formation of the macrocyclic corrin ring. (inferred from compound structure)Siroheme (or sirohaem) is a heme-like prosthetic group used by some enzymes to accomplish the six-electron reduction of sulfur and nitrogen. Siroheme is synthesized from uroporphyrinogen III, a heme and vitamin B12 precursor. It plays a major role in the sulfur assimilation pathway: converting sulfite to a biologically useful sulfide, which can be incorporated into the organic compound homocysteine. (WikiPedia)Iron(2+) (2S,3S,7S,8S)-2,7,13,17-tetrakis(2-carboxyethyl)-3,8,12,18-tetrakis(carboxymethyl)-3,8-dimethyl-7,8-dihydro-2H,3H-porphine-21,23-diideIron(2+); 3-(2S,3S,7S,8S)-7,13,17-tris(2-carboxyethyl)-3,8,12,18-tetrakis(carboxymethyl)-3,8-dimethyl-2,7-dihydroporphyrin-21,23-diid-2-ylpropanoateIron(2+); 3-(2S,3S,7S,8S)-7,13,17-tris(2-carboxyethyl)-3,8,12,18-tetrakis(carboxymethyl)-3,8-dimethyl-2,7-dihydroporphyrin-21,23-diid-2-ylpropanoic acidC42H44FeN4O16916.661916.2101735133-[(4S,5S,9S,10S,11Z,16Z)-9,15,19-tris(2-carboxyethyl)-5,10,14,20-tetrakis(carboxymethyl)-5,10-dimethyl-21,23,24,25-tetraaza-22-ferrahexacyclo[9.9.3.1³,⁶.1¹³,¹⁶.0⁸,²³.0¹⁸,²¹]pentacosa-1(20),2,6(25),7,11,13(24),14,16,18-nonaen-4-yl]propanoic acid3-[(4S,5S,9S,10S,11Z,16Z)-9,15,19-tris(2-carboxyethyl)-5,10,14,20-tetrakis(carboxymethyl)-5,10-dimethyl-21,23,24,25-tetraaza-22-ferrahexacyclo[9.9.3.1³,⁶.1¹³,¹⁶.0⁸,²³.0¹⁸,²¹]pentacosa-1(20),2,6(25),7,11,13(24),14,16,18-nonaen-4-yl]propanoic acid52553-42-1C[C@]1(CC(O)=O)[C@H](CCC(O)=O)\C2=C\C3=C(CC(O)=O)C(CCC(O)=O)=C4\C=C5/N=C(/C=C6\N([Fe]N34)\C(=C/C1=N2)[C@@H](CCC(O)=O)[C@]6(C)CC(O)=O)C(CC(O)=O)=C5CCC(O)=OInChI=1S/C42H46N4O16.Fe/c1-41(17-39(59)60)23(5-9-35(51)52)29-14-27-21(11-37(55)56)19(3-7-33(47)48)25(43-27)13-26-20(4-8-34(49)50)22(12-38(57)58)28(44-26)15-31-42(2,18-40(61)62)24(6-10-36(53)54)30(46-31)16-32(41)45-29;/h13-16,23-24H,3-12,17-18H2,1-2H3,(H10,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62);/q;+2/p-2/t23-,24-,41+,42+;/m1./s1DLKSSIHHLYNIKN-QIISWYHFSA-LCytosollogp1.07logs-3.85solubility1.28e-01 g/lpka_strongest_acidic2.79iupac3-[(4S,5S,9S,10S,11Z,16Z)-9,15,19-tris(2-carboxyethyl)-5,10,14,20-tetrakis(carboxymethyl)-5,10-dimethyl-21,23,24,25-tetraaza-22-ferrahexacyclo[9.9.3.1³,⁶.1¹³,¹⁶.0⁸,²³.0¹⁸,²¹]pentacosa-1(20),2,6(25),7,11,13(24),14,16,18-nonaen-4-yl]propanoic acidaverage_mass916.661mono_mass916.210173513smilesC[C@]1(CC(O)=O)[C@H](CCC(O)=O)\C2=C\C3=C(CC(O)=O)C(CCC(O)=O)=C4\C=C5/N=C(/C=C6\N([Fe]N34)\C(=C/C1=N2)[C@@H](CCC(O)=O)[C@]6(C)CC(O)=O)C(CC(O)=O)=C5CCC(O)=OformulaC42H44FeN4O16inchiInChI=1S/C42H46N4O16.Fe/c1-41(17-39(59)60)23(5-9-35(51)52)29-14-27-21(11-37(55)56)19(3-7-33(47)48)25(43-27)13-26-20(4-8-34(49)50)22(12-38(57)58)28(44-26)15-31-42(2,18-40(61)62)24(6-10-36(53)54)30(46-31)16-32(41)45-29;/h13-16,23-24H,3-12,17-18H2,1-2H3,(H10,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62);/q;+2/p-2/t23-,24-,41+,42+;/m1./s1inchikeyDLKSSIHHLYNIKN-QIISWYHFSA-Lphysiological_charge-8formal_charge0Sulfur metabolismThe sulfur metabolism pathway starts in three possible ways. The first is the uptake of sulfate through an active transport reaction via a sulfate transport system containing an ATP-binding protein which hydrolyses ATP. Sulfate is converted by the sulfate adenylyltransferase enzymatic complex to adenosine phosphosulfate through the addition of adenine from a molecule of ATP, along with one phosphate group. Adenosine phosphosulfate is further converted to phoaphoadenosine phosphosulfate through an ATP hydrolysis and dehydrogenation reaction by the adenylyl-sulfate kinase. Phoaphoadenosine phosphosulfate is finally dehydrogenated and converted to sulfite by phosphoadenosine phosphosulfate reductase. This reaction requires magnesium, and adenosine 3',5'-diphosphate is the bi-product. A thioredoxin is also oxidized. Sulfite can also be produced from the dehydrogenation of cyanide along with the conversion of thiosulfate to thiocyanate by the thiosulfate sulfurtransferase enzymatic complex. Sulfite next undergoes a series of reactions that lead to the production of pyruvic acid, which is a precursor for pathways such as gluconeogenesis. The first reaction in this series is the conversion of sulfite to hydrogen sulfide through hygrogenation and the deoxygenation of sulfite to form a water molecule. The reaction is catalyzed by the sulfite reductase [NADPH] flavoprotein alpha and beta components. Siroheme, 4Fe-4S, flavin mononucleotide, and FAD function as cofactors or prosthetic groups. Hydrogen sulfide next undergoes dehydrogenation in a reversible reaction to form L-Cysteine and acetic acid, via the cysteine synthase complex and the coenzyme pyridoxal 5'-phosphate. L-Cysteine is dehydrogenated and converted to 2-aminoacrylic acid (a bronsted acid) and hydrogen sulfide(which may be reused) by a larger enzymatic complex composed of cysteine synthase A/B, protein malY, cystathionine-β-lyase, and tryptophanase, along with the coenzyme pyridoxal 5'-phosphate. 2-aminoacrylic acid isomerizes to 2-iminopropanoate, which along with a water molecule and a hydrogen ion is lastly converted to pyruvic acid and ammonium in a spontaneous fashion.
The second possible initial starting point for sulfur metabolism is the import of taurine(an alternate sulfur source) into the cytoplasm via the taurine ABC transporter complex. Taurine, oxoglutaric acid, and oxygen are converted to sulfite by the alpha-ketoglutarate-dependent taurine dioxygenase. Carbon dioxide, succinic acid, and aminoacetaldehyde are bi-products of this reaction. Sulfite next enters pyruvic acid synthesis as already described.
The third variant of sulfur metabolism starts with the import of an alkyl sulfate into the cytoplasm via an aliphatic sulfonate ABC transporter complex which hydrolyses ATP. The alkyl sulfate is dehydrogenated and along with oxygen is converted to sulfite and an aldehyde by the FMNH2-dependent alkanesulfonate monooxygenase enzyme. Water and flavin mononucleotide(which is used in a subsequent reaction as a prosthetic group) are also produced. Sulfite is next converted to pyruvic acid by the process already described.PW000922ec00920MetabolicPorphyrin and chlorophyll metabolismec00860Porphyrin metabolismThe metabolism of porphyrin begins with with glutamic acid being processed by an ATP-driven glutamyl-tRNA synthetase by interacting with hydrogen ion and tRNA(Glu), resulting in amo, pyrophosphate and L-glutamyl-tRNA(Glu) Glutamic acid. Glutamic acid can be obtained as a result of L-glutamate metabolism pathway, glutamate / aspartate : H+ symporter GltP, glutamate:sodium symporter or a glutamate / aspartate ABC transporter .
L-glutamyl-tRNA(Glu) Glutamic acid interacts with a NADPH glutamyl-tRNA reductase resulting in a NADP, a tRNA(Glu) and a (S)-4-amino-5-oxopentanoate.
This compound interacts with a glutamate-1-semialdehyde aminotransferase resulting a 5-aminolevulinic acid. This compound interacts with a porphobilinogen synthase resulting in a hydrogen ion, water and porphobilinogen. The latter compound interacts with water resulting in hydroxymethylbilane synthase resulting in ammonium, and hydroxymethylbilane.
Hydroxymethylbilane can either be dehydrated to produce uroporphyrinogen I or interact with a uroporphyrinogen III synthase resulting in a water molecule and a uroporphyrinogen III.
Uroporphyrinogen I interacts with hydrogen ion through a uroporphyrinogen decarboxylase resulting in a carbon dioxide and a coproporphyrinogen I
Uroporphyrinogen III can be metabolized into precorrin by interacting with a S-adenosylmethionine through a siroheme synthase resulting in hydrogen ion, an s-adenosylhomocysteine and a precorrin-1. On the other hand, Uroporphyrinogen III interacts with hydrogen ion through a uroporphyrinogen decarboxylase resulting in a carbon dioxide and a Coproporphyrinogen III.
Precorrin-1 reacts with a S-adenosylmethionine through a siroheme synthase resulting in a S-adenosylhomocysteine and a Precorrin-2. The latter compound is processed by a NAD dependent uroporphyrin III C-methyltransferase [multifunctional] resulting in a NADH and a sirohydrochlorin. This compound then interacts with Fe 2+
uroporphyrin III C-methyltransferase [multifunctional] resulting in a hydrogen ion and a siroheme. The siroheme is then processed in sulfur metabolism pathway.
Uroporphyrinogen III can be processed in anaerobic or aerobic condition.
Anaerobic:
Uroporphyrinogen III interacts with an oxygen molecule, a hydrogen ion through a coproporphyrinogen III oxidase resulting in water, carbon dioxide and protoporphyrinogen IX. The latter compound then interacts with an 3 oxygen molecule through a protoporphyrinogen oxidase resulting in 3 hydrogen peroxide and a Protoporphyrin IX
Aerobic:
Uroporphyrinogen III reacts with S-adenosylmethionine through a coproporphyrinogen III dehydrogenase resulting in carbon dioxide, 5-deoxyadenosine, L-methionine and protoporphyrinogen IX. The latter compound interacts with a meanquinone through a protoporphyrinogen oxidase resulting in protoporphyrin IX.
The protoporphyrin IX interacts with Fe 2+ through a ferrochelatase resulting in a hydrogen ion and a ferroheme b. The ferroheme b can either be incorporated into the oxidative phosphorylation as a cofactor of the enzymes involved in that pathway or it can interact with hydrogen peroxide through a catalase HPII resulting in a heme D. Heme D can then be incorporated into the oxidative phosphyrlation pathway as a cofactor of the enzymes involved in that pathway. Ferroheme b can also interact with water and a farnesyl pyrophosphate through a heme O synthase resulting in a release of pyrophosphate and heme O. Heme O is then incorporated into the Oxidative phosphorylation pathway.
PW000936MetabolicFlavin biosynthesisThe process of flavin biosynthesis starts with GTP being metabolized by interacting with 3 molecules of water through a GTP cyclohydrolase resulting in a release of formic acid, a pyrophosphate, two hydrog ions and 2,5-diamino-6-(5-phospho-D-ribosylamino)pyrimidin-4(3H)-one or 2,5-Diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine. Either of these compounds interacts with a water molecule and a hydrogen ion through a fused diaminohydroxyphosphoribosylaminopyrimidine deaminase / 5-amino-6-(5-phosphoribosylamino)uracil reductase resulting in an ammonium and 5-amino-6-(5-phospho-D-ribosylamino)uracil. This compound then interacts with a hydrogen ion through a NADPH dependent fused diaminohydroxyphosphoribosylaminopyrimidine deaminase / 5-amino-6-(5-phosphoribosylamino)uracil reductase resulting in the release of a NADP and a 5-amino-6-(5-phospho-D-ribitylamino)uracil. This compound then interacts with a water molecule through a 5-amino-6-(5-phospho-D-ribitylamino)uracil phosphatase resulting in a release of a phosphate, and a 5-amino-6-(D-ribitylamino)uracil.
D-ribulose 5-phosphate interacts with a3,4-dihydroxy-2-butanone 4-phosphate synthase resulting in the release of formic acid, a hydrogen ion and 1-deoxy-L-glycero-tetrulose 4-phosphate.
A 5-amino-6-(D-ribitylamino)uracil and 1-deoxy-L-glycero-tetrulose 4-phosphate interact through a 6,7-dimethyl-8-ribityllumazine synthase resulting in the release of 2 water molecules, a phosphate, a hydrogen ion and a 6,7-dimethyl-8-(1-D-ribityl)lumazine.
The latter compound then interacts with a hydrogen ion through a riboflavin synthase resulting in the release of a riboflavin and a 5-amino-6-(d-ribitylamino)uracil.
The riboflavin is then phosphorylated through an ATP dependent riboflavin kinase resulting in the release of a ADP, a hydrogen ion and a FLAVIN MONONUCLEOTIDE.
The flavin mononucleotide interad with a hydrogen ion and an ATP through the riboflavin kinase resulting in the release of a pyrophosphate and Flavin Adenine dinucleotide. This compound is then exported into the periplasm through a FMN/FAD exporter.
PW001971Metabolicsiroheme biosynthesisPWY-5194Specdb::EiMs5527Specdb::NmrOneD338188Specdb::NmrOneD338189Specdb::NmrOneD338190Specdb::NmrOneD338191Specdb::NmrOneD338192Specdb::NmrOneD338193Specdb::NmrOneD338194Specdb::NmrOneD338195Specdb::NmrOneD338196Specdb::NmrOneD338197Specdb::NmrOneD338198Specdb::NmrOneD338199Specdb::NmrOneD338200Specdb::NmrOneD338201Specdb::NmrOneD338202Specdb::NmrOneD338203Specdb::NmrOneD338204Specdb::NmrOneD338205Specdb::NmrOneD338206Specdb::NmrOneD338207Specdb::MsMs25739Specdb::MsMs25740Specdb::MsMs25741Specdb::MsMs32297Specdb::MsMs32298Specdb::MsMs32299439303108937C0074828599SIROHEMEKeseler, I. M., Collado-Vides, J., Santos-Zavaleta, A., Peralta-Gil, M., Gama-Castro, S., Muniz-Rascado, L., Bonavides-Martinez, C., Paley, S., Krummenacker, M., Altman, T., Kaipa, P., Spaulding, A., Pacheco, J., Latendresse, M., Fulcher, C., Sarker, M., Shearer, A. G., Mackie, A., Paulsen, I., Gunsalus, R. P., Karp, P. D. (2011). "EcoCyc: a comprehensive database of Escherichia coli biology." Nucleic Acids Res 39:D583-D590.21097882Kanehisa, M., Goto, S., Sato, Y., Furumichi, M., Tanabe, M. (2012). "KEGG for integration and interpretation of large-scale molecular data sets." Nucleic Acids Res 40:D109-D114.22080510van der Werf, M. J., Overkamp, K. M., Muilwijk, B., Coulier, L., Hankemeier, T. (2007). "Microbial metabolomics: toward a platform with full metabolome coverage." Anal Biochem 370:17-25.17765195Winder, C. L., Dunn, W. B., Schuler, S., Broadhurst, D., Jarvis, R., Stephens, G. M., Goodacre, R. (2008). "Global metabolic profiling of Escherichia coli cultures: an evaluation of methods for quenching and extraction of intracellular metabolites." Anal Chem 80:2939-2948.18331064Siroheme synthaseP0AEA8CYSG_ECOLIcysGhttp://ecmdb.ca/proteins/P0AEA8.xmlIron + Sirohydrochlorin >3 Hydrogen ion + SirohemeSIROHEME-FERROCHELAT-RXNSiroheme + 2 Hydrogen ion <> Fe2+ + SirohydrochlorinR02864Sirohydrochlorin + Iron <> Hydrogen ion + SirohemeSIROHEME-FERROCHELAT-RXNSiroheme + 2 Hydrogen ion > Sirohydrochlorin + IronSirohydrochlorin + Iron >2 Hydrogen ion + SirohemePW_R003492