chembox verifiedrevid 443338221 ImageFile Ref chemboximage correct ?? ImageFile Homocysteine racemic.png ImageSize 180px ImageName Skeletal formula ImageFile1 L Homocysteine 3D balls.png ImageSize1 120px ... Section7 Chembox Hazards EUIndex FlashPt Autoignition Homocysteine IPA h m s sti n is a non ... sup sup methyl group. Homocysteine can be recycled into methionine or converted into cysteine with the aid of B vitamins. While detection of high levels of homocysteine has been linked to cardiovascular disease, lowering homocysteine levels may not improve outcomes. ref cite journal author Mart Carvajal AJ, Sol I, Lathyris D, Salanti G title Homocysteine lowering interventions for preventing cardiovascular ... ref Structure Homocysteine exists at neutral pH values as a zwitterion . File Betain Homocystein.png thumb right 300px Betatine form of S homocysteine left and R homocysteine right Biosynthesis and biochemical roles Homocysteine is not obtained from the diet. ref name AnRvNutrition1999 Selhub cite journal author Selhub, J. title Homocysteine metabolism journal Annual Review of Nutrition year 1999 ... small L small homocysteine. small L small Homocysteine has two primary fates conversion via tetrahydrofolate ... acid cysteine via homocysteine. Cystathionine beta synthase Cystathionine synthase catalyses the condensation of homocysteine and serine to give cystathionine . This reaction uses pyridoxine vitamin ... thumb Two of homocysteine s main biochemical roles. Homocysteine is seen in the left middle of the image ... or used to create cysteine and alpha ketobuterate. Methionine salvage Homocysteine can be recycled ... synthase . Other reactions of biochemical significance Homocysteine can cyclize to give homocysteine thiolactone , a five membered heterocycle . Because of this self looping reaction, homocysteine ..., proposed and verified, of homocysteine on human health Elevated homocysteine Deficiencies of the vitamins ... cobalamin can lead to high homocysteine levels. ref name AmJClinNutrition1994 Miller cite journal author ... more details
enzyme Name homocysteine S methyltransferase EC number 2.1.1.10 CAS number 9012 40 2 IUBMB EC number 2 1 1 10 GO code 0008898 image width caption In enzymology , a homocysteine S methyltransferase EC number 2.1.1.10 is an enzyme that catalysis catalyzes the chemical reaction S adenosyl L methionine L homocysteine math rightleftharpoons math S adenosyl L homocysteine L methionine Thus, the two substrate biochemistry substrates of this enzyme are S Adenosyl methionine S adenosyl methionine and L homocysteine , whereas its two product chemistry products are S adenosylhomocysteine and L methionine . This enzyme belongs to the family of transferase s, specifically those transferring one carbon group methyltransferases. The systematic name of this enzyme class is S adenosyl L methionine L homocysteine S methyltransferase . Other names in common use include S adenosylmethionine homocysteine transmethylase , S methylmethionine homocysteine transmethylase , adenosylmethionine transmethylase , methylmethionine homocysteine methyltransferase , adenosylmethionine homocysteine methyltransferase , homocysteine methylase , homocysteine methyltransferase , homocysteine transmethylase , L homocysteine S methyltransferase , S adenosyl L methionine L homocysteine methyltransferase , S adenosylmethionine homocysteine transmethylase , and S adenosylmethionine homocysteine methyltransferase . This enzyme participates in methionine metabolism . References reflist 1 cite journal author Balish E, Shapiro SK date 1967 title Methionine biosynthesis in Escherichia coli induction and repression of methylmethionine or adenosylmethionine homocysteine methyltransferase journal Arch. Biochem. Biophys. volume 119 pages 62&ndash 8 pmid 4861151 doi 10.1016 0003 9861 67 90429 8 issue 1 cite journal author Shapiro SK date 1958 title Adenosylmethionine homocysteine transmethylase journal Biochim. Biophys. Acta ... homocysteine transmethylases journal Biochim. Biophys. Acta volume 36 pages 241&ndash 244 doi 10.1016 ... more details
enzyme Name homocysteine desulfhydrase EC number 4.4.1.2 CAS number 9024 41 3 IUBMB EC number 4 4 1 2 GO code 0047982 image width caption In enzymology , a homocysteine desulfhydrase EC number 4.4.1.2 is an enzyme that catalysis catalyzes the chemical reaction L homocysteine H sub 2 sub O math rightleftharpoons math hydrogen sulfide NH sub 3 sub 2 oxobutanoate Thus, the two substrate biochemistry substrates of this enzyme are L homocysteine and water H sub 2 sub O , whereas its 3 product chemistry products are hydrogen sulfide , ammonia NH sub 3 sub , and 2 oxobutanoate . This enzyme belongs to the family of lyase s, specifically the class of carbon sulfur lyases. The systematic name of this enzyme class is L homocysteine hydrogen sulfide lyase deaminating 2 oxobutanoate forming . Other names in common use include homocysteine desulfurase, L homocysteine hydrogen sulfide lyase , and deaminating . This enzyme participates in nitrogen metabolism and sulfur metabolism . It employs one cofactor biochemistry cofactor , pyridoxal phosphate . References reflist 1 cite journal author KALLIO RE date 1951 title Function of pyridoxal phosphate in desulfhydrase systems of Proteus morganii journal J. Biol. Chem. volume 192 pages 371&ndash 7 pmid 14917685 issue 1 enzyme stub Category EC 4.4.1 Category Pyridoxal phosphate enzymes Category Enzymes of unknown structure ... more details
enzyme Name thetin homocysteine S methyltransferase EC number 2.1.1.3 CAS number 9029 76 9 IUBMB EC number 2 1 1 3 GO code 0047149 image width caption In enzymology , a thetin homocysteine S methyltransferase EC number 2.1.1.3 is an enzyme that catalysis catalyzes the chemical reaction dimethylsulfonioacetate L homocysteine math rightleftharpoons math S methylthioglycolate L methionine Thus, the two substrate biochemistry substrates of this enzyme are dimethylsulfonioacetic acid and L homocysteine , whereas its two product chemistry products are S methylthioglycolic acid and L methionine . This enzyme belongs to the family of transferase s, specifically those transferring one carbon group methyltransferases. The systematic name of this enzyme class is dimethylsulfonioacetic acid L homocysteine S methyltransferase . Other names in common use include dimethylthetin homocysteine methyltransferase , and thetin homocysteine methylpherase . References reflist 1 cite journal author KLEE WA, RICHARDS HH, CANTONI GL date 1961 title The synthesis of methionine by enzymic transmethylation. VII Existence of two separate homocysteine methylpherases on mammalian liver journal Biochim. Biophys. Acta. volume 54 issue 1 pages 157&ndash 64 pmid 14456704 doi 10.1016 0006 3002 61 90948 9 cite journal author MAW GA date 1956 title Thetin homocysteine transmethylase a preliminary manometric study of the enzyme from rat liver journal Biochem. J. volume 63 pages 116&ndash 24 pmid 13315256 issue 1 pmc 1216008 cite journal author MAW GA date 1958 title Thetin homocysteine transmethylase some further characteristics of the enzyme from rat liver journal Biochem. J. volume 70 pages 168&ndash 73 pmid 13584318 issue 1 pmc 1196643 transferase stub Category EC 2.1.1 Category Enzymes of unknown structure it Tetina omocisteina S metiltransferasi ja S ... more details
enzyme Name betaine homocysteine S methyltransferase EC number 2.1.1.5 CAS number 9029 78 1 IUBMB EC number 2 1 1 5 GO code 0047150 image BHMT ribbon view.png width caption Crystal structure of rat liver betaine homocysteine s methyltransferase. ref name pmid15099744 PDB 1UMY cite journal author Gonz lez B, Pajares MA, Mart nez Ripoll M, Blundell TL, Sanz Aparicio J title Crystal structure of rat liver betaine homocysteine s methyltransferase reveals new oligomerization features and conformational ... homocysteine S methyltransferase also known as betaine homocysteine methyltransferase is a zinc metallo enzyme that catalyzes the transfer of a methyl group from betaine to homocysteine to produce ... Sala D title Betaine homocysteine S methyltransferase just a regulator of homocysteine metabolism ... doi 10.1007 s00018 006 6249 6 url issn ref betaine homocysteine dimethylglycine methionine This enzyme ... Garrow TA title Purification, kinetic properties, and cDNA cloning of mammalian betaine homocysteine ... homocysteine methyltransferase expression in porcine and human tissues and chromosomal localization ... Betaine homocysteine methyltransferase 2 cDNA cloning, gene sequence, physical mapping, and expression ... Szegedi SS, Castro CC, Koutmos M, Garrow TA title Betaine homocysteine S methyltransferase 2 is an S methylmethionine homocysteine methyltransferase journal J. Biol. Chem. volume 283 issue 14 pages ... encoded by a separate gene. protein Name betaine homocysteine methyltransferase caption image width ... 2.1.1.5 Chromosome 5 Arm q Band 13.1 LocusSupplementaryData q15 protein Name betaine homocysteine ... cite journal author Sunden SL, Renduchintala MS, Park EI, Miklasz SD, Garrow TA title Betaine homocysteine ... pmid 9281325 doi 10.1006 abbi.1997.0246 url ref Clinical significance Anomalies in homocysteine metabolism .... VII Existence of two separate homocysteine methylpherases on mammalian liver journal Biochim ... External links MeshName Betaine Homocysteine Methyltransferase EC number 2.1.1.5 transferase stub ... more details
DISPLAYTITLE S Adenosyl small L small homocysteine chembox verifiedrevid 460764948 Name S Adenosyl small L small homocysteine ImageFile S Adenosyl L homocysteine.svg ImageSize IUPACName S 5 Deoxyadenos 5 yl small L small homocysteine OtherNames AdoHcy, 2 S adenosyl small L small homocysteine, br 5 S 3 Amino 3 carboxypropyl 5 thioadenosine S adenosylhomocysteine, SAH Section1 Chembox Identifiers CASNo Ref cascite correct CAS CASNo 979 92 0 ChEMBL Ref ebicite correct EBI ChEMBL 418052 PubChem 439155 ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 388301 SMILES O C O C H N CCSC C H 3O C H n2cnc1c ncnc12 N C H O C H 3O InChI 1 C14H20N6O5S c15 6 14 23 24 1 2 26 3 7 9 21 10 22 13 25 7 20 5 19 8 11 16 17 4 18 12 8 20 h4 7,9 10,13,21 22H,1 3,15H2, H,23,24 H2,16,17,18 t6 ,7 ,9 ,10 ,13 m0 s1 InChIKey ZJUKTBDSGOFHSH WFMPWKQPBX StdInChI Ref stdinchicite correct chemspider StdInChI 1S C14H20N6O5S c15 6 14 23 24 1 2 26 3 7 9 21 10 22 13 25 7 20 5 19 8 11 16 17 4 18 12 8 20 h4 7,9 10,13,21 22H,1 3,15H2, H,23,24 H2,16,17,18 t6 ,7 ,9 ,10 ,13 m0 s1 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey ZJUKTBDSGOFHSH WFMPWKQPSA N MeSHName S Adenosylhomocysteine ChEBI Ref ebicite correct EBI ChEBI 16680 KEGG Ref keggcite correct kegg KEGG C00021 Section2 Chembox Properties Formula C sub 14 sub H sub 20 sub N sub 6 sub O sub 5 sub S C 14 H 20 N 6 O 5 S 1 MolarMass 384.412 Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition S Adenosyl small L small homocysteine SAH is an amino acid derivative used in several metabolic pathways in most organisms. It is an intermediate in the synthesis of cysteine and adenosine . SAH is formed by the demethylation of S Adenosyl L methionine S adenosyl small L small methionine SAM . External links http biocyc.org ECOLI NEW IMAGE?type COMPOUND&object ADENOSYL HOMO CYS BioCYC E.Coli K 12 Compound S adenosyl L homocysteine Amino acid metabolism intermediates DEFAULTSORT Adenosyl L homocysteine ... more details
enzyme Name 5 methyltetrahydropteroyltriglutamate homocysteine S methyltransferase EC number 2.1.1.14 CAS number 9068 29 5 IUBMB EC number 2 1 1 14 GO code 0003871 image width caption In enzymology , a 5 methyltetrahydropteroyltriglutamate homocysteine S methyltransferase EC number 2.1.1.14 is an enzyme that catalysis catalyzes the chemical reaction 5 methyltetrahydropteroyltri L glutamate L homocysteine math rightleftharpoons math tetrahydropteroyltri L glutamate L methionine Thus, the two substrate biochemistry substrates of this enzyme are 5 methyltetrahydropteroyltri L glutamatic acid and L homocysteine , whereas its two product chemistry products are tetrahydropteroyltri L glutamatic acid and L methionine . This enzyme belongs to the family of transferase s, specifically those transferring one carbon group methyltransferases. The systematic name of this enzyme class is 5 methyltetrahydropteroyltri L glutamate L homocysteine S methyltransferase . Other names in common use include tetrahydropteroyltriglutamate methyltransferase , homocysteine methylase , methyltransferase, tetrahydropteroylglutamate homocysteine transmethylase , methyltetrahydropteroylpolyglutamate homocysteine methyltransferase , cobalamin independent methionine synthase , methionine synthase cobalamin independent , and MetE . This enzyme participates in methionine metabolism . It has 2 cofactor biochemistry cofactors orthophosphate , and zinc . Structural studies As of late 2007, 9 tertiary structure structures have been solved for this class of enzymes, with Protein Data Bank PDB accession codes PDB link 1T7L , PDB link 1U1H , PDB link 1U1J , PDB link 1U1U , PDB link 1U22 , PDB link 1XDJ , PDB link 1XPG ... to homocysteine in Escherichia coli journal Biochem. J. volume 92 pages 497&ndash 504 ... Purification and properties of 5 methyltetrahydropteroyltriglutamate homocysteine transmethylase ... of zinc in the methylation of homocysteine journal J. Am. Chem. Soc. volume 120 pages 8410&ndash ... more details
Pfam box Symbol Ad hcy hydrolase Name S adenosyl L homocysteine hydrolase image PDB 1b3r EBI.jpg width caption Structure of S adenosylhomocysteine hydrolase from rat liver. ref name pmid10387078 cite journal author Hu Y, Komoto J, Huang Y, et al. title Crystal structure of S adenosylhomocysteine hydrolase from rat liver journal Biochemistry volume 38 issue 26 pages 8323 33 year 1999 month June pmid 10387078 doi 10.1021 bi990332k url ref Pfam PF05221 InterPro IPR000043 SMART PROSITE PDOC00603 SCOP 1b3r TCDB OPM family OPM protein PDB PDB2 1a7a , PDB2 1b3r , PDB2 1d4f , PDB2 1k0u , PDB2 1ky4 , PDB2 1ky5 , PDB2 1li4 , PDB2 1v8b , PDB2 1xwf Infobox protein family Symbol AdoHcyase NAD Name AdoHcyase NAD binding domain image PDB 1ky5 EBI.jpg width caption d244e mutant s adenosylhomocysteine hydrolase refined with noncrystallographic restraints Pfam PF00670 Pfam clan CL0063 InterPro IPR015878 SMART PROSITE PDOC00603 MEROPS SCOP 1b3r TCDB OPM family OPM protein CAZy CDD S adenosyl L homocysteine hydrolase EC number 3.3.1.1 AdoHcyase is an enzyme of the activated methyl cycle, responsible for the reversible hydration of S adenosyl L homocysteine into adenosine and homocysteine . AdoHcyase is an ubiquitous enzyme which binds and requires nicotinamide adenine dinucleotide NAD sup sup as a cofactor. AdoHcyase is a highly conserved protein ref name PUB00004791 cite journal author Sganga MW, Aksamit RR, Cantoni GL, Bauer CE title Mutational and nucleotide sequence analysis of S adenosyl L homocysteine hydrolase from Rhodobacter capsulatus journal Proc. Natl. Acad. Sci. U.S.A. volume 89 issue 14 pages 6328 6332 year 1992 pmid 1631127 doi 10.1073 pnas.89.14.6328 pmc 49494 ref of about 430 to 470 amino acids. The family contains a glycine rich region in the central part of AdoHcyase a region thought to be involved in NAD binding. This protein may use the morpheein model of allosteric regulation . ref name pmid22182754 cite journal author T. Selwood and E. K. Jaffe. title Dynamic dissociating ... more details
The transsulfuration pathway is a metabolic pathway involving the interconversion of cysteine and homocysteine , through the intermediate cystathionine . In eukaryotes, such as humans, the transsulfuration pathway is critical for creating cysteine from the essential amino acid methionine. Methionine is first converted to homocysteine by demethylation, which is then converted to the amino acid cysteine via the transsulfuration pathway. While methionine is considered an essential amino acid, cysteine becomes an essential amino acid when the transsulfuration pathway is defective. In organisms that synthesize cysteine in sulfur assimilation such as bacteria and yeast, the transsulfuration pathway works in reverse. The production of homocysteine through transsulfuration allows the conversion of this intermediate to methionine , through a methylation reaction carried out by 5 Methyltetrahydrofolate homocysteine methyltransferase methionine synthase . biochemistry stub Category Nitrogen metabolism Category Sulfur metabolism Category Metabolic pathways vi Chu tr nh chuy n sunfua h a ... more details
Transmethylation is a biologically important organic chemical reaction in which a methyl group is transferred from one compound to another. An example of transmethylation is the recovery of methionine from homocysteine . In order to sustain sufficient reaction rates during metabolic stress, this reaction requires adequate levels of vitamin B sub 12 sub and folic acid. Methyl tetrahydrofolate delivers methyl groups to form the active methyl form of vitamin B sub 12 sub that is required for methylation of homocysteine. Deficiencies of vitamin B sub 12 sub or folic acid cause increased levels of circulatiing homocysteine. Elevated homocysteine is a risk factor for cardiovascular disease and is linked to the metabolic syndrome insulin insensitivity . Transmethylation is decreased sometimes in children with autism. See also Methylation Category Organic reactions organic chem stub de Transmethylierung ... more details
enzyme Name S adenosylhomocysteine deaminase EC number 3.5.4.28 CAS number 125149 24 8 IUBMB EC number 3 5 4 28 GO code 0050270 image width caption In enzymology , a S adenosylhomocysteine deaminase EC number 3.5.4.28 is an enzyme that catalysis catalyzes the chemical reaction S adenosyl L homocysteine H sub 2 sub O math rightleftharpoons math S inosyl L homocysteine NH sub 3 sub Thus, the two substrate biochemistry substrates of this enzyme are S adenosyl L homocysteine and water H sub 2 sub O , whereas its two product chemistry products are S inosyl L homocysteine and ammonia NH sub 3 sub . This enzyme belongs to the family of hydrolase s, those acting on carbon nitrogen bonds other than peptide bonds, specifically in cyclic amidines. The systematic name of this enzyme class is S adenosyl L homocysteine aminohydrolase . This enzyme is also called adenosylhomocysteine deaminase . References reflist 1 cite journal author Zulty JJ, Speedie MK date 1989 title Purification and characterization of S adenosylhomocysteine deaminase from streptonigrin producing Streptomyces flocculus journal J. Bacteriol. volume 171 pages 6840&ndash 4 pmid 2592350 issue 12 pmc 210584 hydrolase stub Category EC 3.5.4 Category Enzymes of unknown structure ... more details
Kilmer S. McCully is the Chief of Pathology and Laboratory Medicine Services for the United States Department of Veterans Affairs Medical Center. McCully was the first to propose the homocysteine theory of cardiovascular disease , and is the author of the book, The Homocysteine Revolution . ref cite news first Michelle last Stacey title The Fall and Rise of Kilmer McCully url http query.nytimes.com gst fullpage.html?res 9D0DE2D8153DF933A2575BC0A961958260&sec health&spon &pagewanted all publisher The New York Times date 1997 08 10 accessdate 2007 04 12 ref ref cite news first Jeffrey last Kluger title Beyond Cholesterol url http www.time.com time magazine article 0,9171,986793 1,00.html publisher Time Magazine date 1997 08 04 accessdate 2007 04 12 ref Selected papers McCully K S, Vascular pathology of homocysteinemia implications for the pathogenesis of arteriosclerosis , Am. J. Pathol. 1969 , 56 pp. 111 128. McCully K S, Chemical pathology of homocysteine , I. Atherogenesis Ann. Clin. Lab. Sci. 1993 , 23 pp. 477 493. McCully K S, Homocysteine and vascular disease , Nature Med. 1996 , 2 pp. 386 389. McCully K S, Homocysteine, folate, vitamin B6 and cardiovascular disease , J.Am. Med.Assoc. 1998 , 279 pp. 392 393. McCully K S, Atherosclerosis, serum cholesterol and the homocysteine theory a study of 194 consecutive autopsies , J.Am. Med. Sci. 1990 , 299 pp. 217 221. McCully K S, Keeping the Young Elderly Healthy. Homocysteine, vitamins, and vascular disease prevention , Am. J. Clin. Nutr. Nov. 2007 Vol. 86, No. 5, 1563S 8S http www.ajcn.org cgi content full 86 5 1563S Notes div class references small references div Persondata Metadata see Wikipedia Persondata . NAME Maccully, Kilmer S. ALTERNATIVE NAMES SHORT DESCRIPTION DATE OF BIRTH 1934 PLACE OF BIRTH DATE OF DEATH PLACE OF DEATH DEFAULTSORT Maccully, Kilmer S. Category 1934 births Category Living people Category American physicians US med bio stub ... more details
Infobox Disease Name PAGENAME Image L Homocysteine.svg Caption Homocysteine DiseasesDB 29853 ICD10 ICD9 ICD9 270.4 ICDO OMIM MedlinePlus eMedicineSubj neuro eMedicineTopic 578 MeshID Cleanup date April 2011 Hyperhomocysteinemia or hyperhomocysteinaemia is a medical condition characterized by an abnormally large level of homocysteine in the blood . As a consequence of the biochemical reactions in which homocysteine is involved, deficiencies of the vitamins Vitamin B6 pyridoxine B sub 6 sub , folic acid B sub 9 sub , or cyanocobalamin B sub 12 sub can lead to high homocysteine levels. ref name AmJClinNutrition1994 Miller cite journal author Miller JW, Nadeau MR, Smith D, Selhub J title Vitamin B 6 deficiency vs folate deficiency comparison of responses to methionine loading in rats journal American Journal of Clinical Nutrition year 1994 volume 59 pages 1033 1039 pmid 8172087 issue 5 ref Supplementation ... of homocysteine in the bloodstream. ref name ExpertOpPharm2001 Coen cite journal author van Guldener C, Stehouwer CD title Homocysteine lowering treatment an overview journal Expert Opinion ... of homocysteine. There are two common gene defects in the population. The first gene codes .... Citation needed date January 2010 Hyperhomocysteinemia is a high level of homocysteine in human blood. A high level of homocysteine makes a person more prone to endothelial injury, which leads to vascular ... to show that reducing your homocysteine levels will improve your health. In a study designed to see if lowering homocysteine will reduce heart vascular and kidney problems, the results were just ... sub 12 sub 1 mg d . Diabetics usually have elevated homocysteine levels and a higher risk for heart attacks and strokes, so they make an ideal population to study homocysteine s effects on human health. Taking B vitamins did reduce homocysteine, as expected, but unfortunately doubled the patient .... MTHFR is involved in the methylation of homocysteine to methionine. Individuals with MTHFR ... more details
enzyme Name adenosylhomocysteine nucleosidase EC number 3.2.2.9 CAS number 9055 10 1 IUBMB EC number 3 2 2 9 GO code 0008782 image width caption In enzymology , an adenosylhomocysteine nucleosidase EC number 3.2.2.9 is an enzyme that catalysis catalyzes the chemical reaction S adenosyl L homocysteine H sub 2 sub O math rightleftharpoons math S 5 deoxy D ribos 5 yl L homocysteine adenine Thus, the two substrate biochemistry substrates of this enzyme are S adenosyl L homocysteine and water H sub 2 sub O , whereas its two product chemistry products are S 5 deoxy D ribos 5 yl L homocysteine and adenine . This enzyme belongs to the family of hydrolase s, specifically those glycosylases that hydrolyse N glycosyl compounds. The systematic name of this enzyme class is S adenosyl L homocysteine homocysteinylribohydrolase . Other names in common use include S adenosylhomocysteine hydrolase ambiguous , S adenosylhomocysteine nucleosidase , 5 methyladenosine nucleosidase , S adenosylhomocysteine 5 methylthioadenosine nucleosidase , and AdoHcy MTA nucleosidase . This enzyme participates in methionine metabolism . Structural studies As of late 2007, 8 tertiary structure structures have been solved for this class of enzymes, with Protein Data Bank PDB accession codes PDB link 1JYS , PDB link 1NC1 , PDB link 1NC3 , PDB link 1Y6Q , PDB link 1Y6R , PDB link 1Z5N , PDB link 1Z5O , and PDB link 1Z5P . References reflist 1 cite journal author Duerre JA date 1962 title A hydrolytic nucleosidase acting on S adenosylhomocysteine and on 5 methylthioadenosine journal J. Biol. Chem. volume 237 pages 3737&ndash 3741 cite journal author Ferro AJ, Barrett A, Shapiro SK date 1976 title Kinetic properties and the effect of substrate analogues on 5 methylthioadenosine nucleosidase from Escherichia coli journal Biochim. Biophys. Acta. volume 438 pages 487&ndash 94 pmid 782530 issue 2 hydrolase stub Category EC 3.2.2 Category Enzymes of known structure ... more details
MTRR may refer to MTRR gene 5 methyltetrahydrofolate homocysteine methyltransferase reductase , a human gene Memory Type Range Registers , in computer hardware disambig Short pages monitor This long comment was added to the page to prevent it from being listed on Special Shortpages. It and the accompanying monitoring template were generated via Template Long comment. Please do not remove the monitor template without removing the comment as well. ... more details
protein Name S adenosylhomocysteine hydrolase caption image width HGNCid 343 Symbol AHCY AltSymbols EntrezGene 191 OMIM 180960 RefSeq NM 000687 UniProt P23526 PDB ECnumber 3.3.1.1 Chromosome 20 Arm q Band 11.22 LocusSupplementaryData Adenosylhomocysteinase is an enzyme that converts S adenosylhomocysteine to homocysteine and adenosine . External links MeshName Adenosylhomocysteinase hydrolase stub Ether bond hydrolases Amino acid metabolism enzymes fi Adenosyylihomokysteinaasi zh ... more details
Oxycholesterol or 5,6 epoxycholestrol is a form of oxidized cholesterol implicated in atherosclerosis . ref http www.physorg.com news169978803.html Physorg Little known type of cholesterol may pose the greatest heart disease risk ref It is commonly formed from the reaction of fats and oxygen during high temperature cooking such as frying. Also see oxysterol . See also Homocysteine Oxysterol References reflist 2 Vascular diseases biochem stub Category Cardiovascular diseases ... more details
enzyme Name S ribosylhomocysteine lyase EC number 4.4.1.21 CAS number 37288 63 4 IUBMB EC number 4 4 1 21 GO code 0043768 image width caption Infobox protein family Symbol LuxS Name S Ribosylhomocysteinase LuxS image PDB 1joe EBI.jpg width caption crystal structure of autoinducer 2 production protein luxs from heamophilus influenzae Pfam PF02664 Pfam clan CL0094 InterPro IPR003815 SMART PROSITE MEROPS SCOP 1inn TCDB OPM family OPM protein CAZy CDD In enzymology , a S ribosylhomocysteine lyase EC number 4.4.1.21 is an enzyme that catalysis catalyzes the chemical reaction S 5 deoxy D ribos 5 yl L homocysteine math rightleftharpoons math L homocysteine 4S 4,5 dihydroxypentan 2,3 dione Hence, this enzyme has one substrate biochemistry substrate , S 5 deoxy D ribos 5 yl L homocysteine , and two product chemistry products , L homocysteine and 4S 4,5 dihydroxypentan 2,3 dione . This enzyme belongs to the family of lyase s, specifically the class of carbon sulfur lyases. The systematic name of this enzyme class is S 5 deoxy D ribos 5 yl L homocysteine L homocysteine lyase 4S 4,5 dihydroxypentan 2,3 dione forming . Other names in common use include S ribosylhomocysteinase , and LuxS . This enzyme participates in methionine metabolism . The LuxS AI 2 system is one of several quorum sensing Nuclear receptor Mechanism of action mechanism s. AI 2 autoinducer 2 is a cell signalling signalling molecule that functions in interspecies communication by regulating niche specific gene genes with diverse functions in various bacteria, often in response to population density. It is involved in the Biosynthesis synthesis of autoinducer AI 2 autoinducer 2 , which is involved in quorum sensing . LuxS converts S ribosylhomocysteine to homocysteine and 4,5 dihydroxy 2,3 pentanedione DPD DPD can then spontaneously cyclise to active AI 2. ref name pmid16923076 cite journal author van Houdt R, Moons P, Jansen A, Vanoirbeek K, Michiels CW title Isolation and functional analysis of luxS in Serrati ... more details
Merge Cystathionine beta lyase date May 2011 enzyme Name cystathionine beta lyase EC number 4.4.1.8 CAS number 9055 05 4 IUBMB EC number 4 4 1 8 GO code 0004121 image width caption Orphan date February 2009 In enzymology , a cystathionine beta lyase EC number 4.4.1.8 is an enzyme that catalysis catalyzes the chemical reaction L cystathionine H sub 2 sub O math rightleftharpoons math L homocysteine NH sub 3 sub pyruvate Thus, the two substrate biochemistry substrates of this enzyme are L cystathionine and water H sub 2 sub O , whereas its 3 product chemistry products are L homocysteine , ammonia NH sub 3 sub , and pyruvate . This enzyme belongs to the family of lyase s, specifically the class of carbon sulfur lyases. The systematic name of this enzyme class is L cystathionine L homocysteine lyase deaminating pyruvate forming . Other names in common use include beta cystathionase , cystine lyase , cystathionine L homocysteine lyase deaminating , and L cystathionine L homocysteine lyase deaminating . This enzyme participates in 5 metabolism metabolic pathways methionine metabolism , cysteine metabolism , selenoamino acid metabolism , nitrogen metabolism , and sulfur metabolism . It employs one cofactor biochemistry cofactor , pyridoxal phosphate . Structural studies As of late 2007, 5 tertiary structure structures have been solved for this class of enzymes, with Protein Data Bank PDB accession codes PDB link 1CL1 , PDB link 1CL2 , PDB link 1IBJ , PDB link 2FQ6 , and PDB link 2GQN . References reflist 1 cite journal author Anderson NW and Thompson JF date 1979 title Cystine lyase beta cystathionase from turnip roots journal Phytochemistry journal Phytochemistry volume 18 pages 1953&ndash 1958 doi 10.1016 S0031 9422 00 82710 7 issue 12 cite journal author FLAVIN M, SLAUGHTER C date 1964 title CYSTATHIONINE CLEAVAGE ENZYMES OF NEUROSPORA journal J. Biol. Chem. volume 239 pages 2212&ndash 9 pmid 14209950 Category EC 4.4.1 Category Pyridoxal phosphate enzymes Category Enzym ... more details
File Thiolactone types.png thumb right , , , and lactones left to right Thiolactones are a class of heterocyclic compounds in organic chemistry . They are analogs of the more common lactone s in which an oxygen atom is replaced with a sulfur atom. The sulfur atom is within the ring system and adjacent to a carbonyl group . Chemistry Thiolactones can be prepared by dehydration reaction dehydration of thiol containing carboxylic acids. Thiolactones can be hydrolysis hydrolyzed back to the thiol acids under basic conditions. ref cite journal doi 10.1021 jo01377a017 year 1954 last1 Stevens first1 Charles M. last2 Tarbell first2 D. Stanley journal Journal of Organic Chemistry volume 19 issue 12 pages 1996 2003 ref Thiolactones can be opened by reaction at the 4 position via SN2 reaction SN sub 2 sub nucleophilic reactions . ref cite journal doi 10.1021 jo9001728 title SN2 Type Nucleophilic Opening of Thiolactones Thietan 2 ones as a Source of Thioacids for Coupling Reactions year 2009 last1 Crich first1 David last2 Sana first2 Kasinath journal The Journal of Organic Chemistry volume 74 issue 9 pages 3389 3393 pmid 19388715 ref Occurrence The most common thiolactone, homocysteine thiolactone is produced biochemically from homocysteine and it may play a role in protein damage. ref cite journal pmid 10721911 year 2000 last1 Jakubowski first1 H title Homocysteine thiolactone Metabolic origin and protein homocysteinylation in humans volume 130 issue 2S Suppl pages 377S 381S journal The Journal of nutrition ref The thiolactone functional group is also present in some pharmaceutical drugs such as citiolone and erdosteine . References reflist Category Functional groups Category Thiolactones de Thiolactone ... more details
enzyme Name glutathione homocystine transhydrogenase EC number 1.8.4.1 CAS number 9029 40 7 IUBMB EC number 1 8 4 1 GO code 0047139 image width caption In enzymology , a glutathione homocystine transhydrogenase EC number 1.8.4.1 is an enzyme that catalysis catalyzes the chemical reaction 2 glutathione homocystine math rightleftharpoons math glutathione disulfide 2 homocysteine Thus, the two substrate biochemistry substrates of this enzyme are glutathione and homocystine , whereas its two product chemistry products are glutathione disulfide and homocysteine . This enzyme belongs to the family of oxidoreductase s, specifically those acting on a sulfur group of donors with a disulfide as acceptor. The systematic name of this enzyme class is glutathione homocystine oxidoreductase . This enzyme participates in methionine metabolism and glutathione metabolism . References reflist 1 cite journal author Racker E date 1955 title Glutathione homocystine transhydrogenase journal J. Biol. Chem. volume 217 pages 867&ndash 874 pmid 13271447 issue 2 1.8 enzyme stub Category EC 1.8.4 Category Enzymes of unknown structure it Glutatione omocistina transidrogenasi ja ... more details
SAH may refer to Society of Architectural Historians Subarachnoid hemorrhage Sakha language s ISO 639 2 code Sana a International Airport s IATA code Savage Aural Hotbed Sayakhat Airlines ICAO code S adenosyl homocysteine , a S adenosyl methionine SAM by product. Stay at Home as in SAH Mom Stay at Home Mom SETI home People with the surname Chih Tang Sah , American Engineer, Professor at the University of Florida Places Sah, Mali , a village and seat of the N Dodjiga commune of N Dodjiga in the Cercle of Youwaro in the Mopti Region of southern central Mali. Sah, Yemen See also SAHS disambiguation disambig de SAH eo SAH fa SAH it SAH pl SAH ... more details
Andrew G. Bostom Doctor of Medicine MD , Master of Surgery MS is an United States American author and Associate Professor of Medicine at Brown University Medical School. ref citation url http research.brown.edu research profile.php?id 1100923756 accessdate 2011 01 29 title The Directory of Research and Researchers at Brown Andrew Bostom publisher Brown University . ref He is an expert on connections between homocysteine and cardiovascular disease . ref citation last1 Selhub first1 J. last2 Jacques first2 P.F. last3 Bostom first3 A.G. last4 D Agostino first4 R.B. last5 Wilson first5 P.W.F. last6 Belanger first6 A.J. last7 O Leary first7 D.H. last8 Wolf first8 P.A. last9 Schaefer first9 E.J. last10 Rosenberg first10 I.H. issue 5 journal New England Journal of Medicine page 286 publisher Mass Med Soc title Association between plasma homocysteine concentrations and extracranial carotid artery stenosis volume 332 year 1995 citation last1 Jacques first1 P.F. last2 Selhub first2 J. last3 Bostom first3 A.G. last4 Wilson first4 P.W.F. last5 Rosenberg first5 I.H. issue 19 journal New England Journal of Medicine page 1449 publisher Mass Med Soc title The effect of folic acid fortification on plasma folate and total homocysteine concentrations volume 340 year 1999 citation last1 Jacques first1 P.F. last2 Bostom first2 A.G. last3 Williams first3 R.R. last4 Ellison first4 R.C. last5 Eckfeldt first5 J.H. last6 Rosenberg first6 I.H. last7 Selhub first7 J. last8 Rozen first8 R. issue 1 journal Circulation page 7 title Relation between folate status, a common mutation in methylenetetrahydrofolate reductase, and plasma homocysteine concentrations volume 93 year 1996 . ref He is also well known for his writings on Islam ref citation title Bostom s legacy journal Jerusalem Post first Raphael last Israeli date May 16, 2008 . ref he is the author of The Legacy of Jihad 2005 , a work which provides an analysis of Jihad based on an exegesis of translations of Islamic primary source s done b ... more details
called S adenosyl homocysteine. The AHCY gene provides instructions for producing the enzyme S adenosylhomocysteine hydrolase . This enzyme converts the S adenosyl homocysteine into the compound homocysteine . Homocysteine may be converted back to methionine or into another amino acid, cysteine ... more details
refimprove date December 2009 Infobox Disease Name PAGENAME Image L Homocysteine.svg Caption Homocysteine DiseasesDB 5991 ICD10 ICD10 E 72 1 e 70 ICD9 ICD9 270.4 ICDO OMIM 236200 MedlinePlus 001199 eMedicineSubj derm eMedicineTopic 708 MeshID D006712 Homocystinuria , also known as cystathionine beta synthase deficiency or CBS deficiency , ref name omim OMIM 236200 ref is an inherited disorder of the metabolism of the amino acid methionine , often involving cystathionine beta synthase . It is an inherited autosomal recessive trait , which means a child needs to inherit a copy of the defective gene from each parent to be affected. Presentation This defect leads to a multisystemic disorder of the connective tissue , muscle s, Central nervous system CNS , and cardiovascular system . Homocystinuria represents a group of hereditary metabolic disorder s characterized by an accumulation of homocysteine in the blood plasma serum and an increased excretion of homocysteine in the urine . Infants appear to be normal and early symptoms, if any are present, are vague. Possible Signs and symptoms A family history of homocystinuria ref name pmid18423051 cite journal author Maillot F, Kraus JP, Lee PJ title Environmental influences on familial discordance of phenotype in people with homocystinuria a case report journal J Med Case Reports volume 2 issue 1 pages 113 year 2008 pmid 18423051 pmc 2377250 doi 10.1186 1752 1947 2 113 url http www.jmedicalcasereports.com content 2 113 ref Flushing physiology Flush across the cheeks Musculoskeletal Tall, thin build resembling Marfanoid Marfanoid habitus ref name omim Long limbs dolichostenomelia High arched feet pes cavus Knock knees genu valgum Pectus excavatum and Pectus carinatum Mental retardation Seizures Psychiatric disease Eye anomalies ectopia ... of homocysteine by promoting the conversion of homocysteine back to methionine. The re formed ... into protein is converted to S adenosyl methionine which goes on to form homocysteine ... more details
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