Entry Name Cysteine and methionine metabolism
Description Cysteine and methionine are sulfur-containing amino acids. Cysteine is synthesized from serine through different pathways in different organism groups. In bacteria and plants, cysteine is converted from serine (via acetylserine) by transfer of hydrogen sulfide [MD:
M00021 ]. In animals, methionine-derived homocysteine is used as sulfur source and its condensation product with serine (cystathionine) is converted to cysteine [MD:
M00338 ]. Cysteine is metabolized to pyruvate in multiple routes. Methionine is an essential amino acid, which animals cannot synthesize. In bacteria and plants, methionine is synthesized from aspartate [MD:
M00017 ]. S-Adenosylmethionine (SAM), synthesized from methionine and ATP, is a methyl group donor in many important transfer reactions including DNA methylation for regulation of gene expression. SAM may also be used to regenerate methionine in the methionine salvage pathway [MD:
M00034 ].
Class Metabolism; Amino acid metabolismBRITE hierarchy
Pathway map ko00270 Cysteine and methionine metabolism
Module M00017 Methionine biosynthesis, aspartate => homoserine => methionine [PATH:ko00270 ]
M00338 Cysteine biosynthesis, homocysteine + serine => cysteine [PATH:ko00270 ]
M00368 Ethylene biosynthesis, methionine => ethylene [PATH:ko00270 ]
M00609 Cysteine biosynthesis, methionine => cysteine [PATH:ko00270 ]
Other DBs Orthology K00544 BHMT; betaine-homocysteine S-methyltransferase [EC:2.1.1.5 ]
K00548 metH, MTR; 5-methyltetrahydrofolate--homocysteine methyltransferase [EC:2.1.1.13 ]
K00549 metE; 5-methyltetrahydropteroyltriglutamate--homocysteine methyltransferase [EC:2.1.1.14 ]
K00811 ASP5; aspartate aminotransferase, chloroplastic [EC:2.6.1.1 ]
K00816 CCBL; kynurenine---oxoglutarate transaminase / cysteine-S-conjugate beta-lyase / glutamine---phenylpyruvate transaminase [EC:2.6.1.7 4.4.1.13 2.6.1.64 ]
K00826 E2.6.1.42, ilvE; branched-chain amino acid aminotransferase [EC:2.6.1.42 ]
K00827 AGXT2; alanine-glyoxylate transaminase / (R)-3-amino-2-methylpropionate-pyruvate transaminase [EC:2.6.1.44 2.6.1.40 ]
K00837 ISS1, VAS1; aromatic aminotransferase
K01243 mtnN, mtn, pfs; adenosylhomocysteine nucleosidase [EC:3.2.2.9 ]
K01505 E3.5.99.7; 1-aminocyclopropane-1-carboxylate deaminase [EC:3.5.99.7 ]
K01566 E3.13.1.9; S-inosyl-L-homocysteine hydrolase
K01752 E4.3.1.17, sdaA, sdaB, tdcG; L-serine dehydratase [EC:4.3.1.17 ]
K01767 cupin; S-methyl-1-thioxylulose 5-phosphate methylthiotransferase
K08965 mtnW; 2,3-diketo-5-methylthiopentyl-1-phosphate enolase [EC:5.3.2.5 ]
K08966 mtnX; 2-hydroxy-3-keto-5-methylthiopentenyl-1-phosphate phosphatase [EC:3.1.3.87 ]
K08969 mtnE, mtnV; L-glutamine---4-(methylsulfanyl)-2-oxobutanoate aminotransferase [EC:2.6.1.117 ]
K10764 metZ; O-succinylhomoserine sulfhydrylase [EC:2.5.1.-]
K11204 GCLC; glutamate--cysteine ligase catalytic subunit [EC:6.3.2.2 ]
K11205 GCLM; glutamate--cysteine ligase regulatory subunit
K12339 cysM; S-sulfo-L-cysteine synthase (O-acetyl-L-serine-dependent) [EC:2.5.1.144 ]
K13061 rhlI, phzI, solI, cepI, tofI; acyl homoserine lactone synthase [EC:2.3.1.184 ]
K14454 GOT1; aspartate aminotransferase, cytoplasmic [EC:2.6.1.1 ]
K14455 GOT2; aspartate aminotransferase, mitochondrial [EC:2.6.1.1 ]
K16845 suyA; (2R)-sulfolactate sulfo-lyase subunit alpha [EC:4.4.1.24 ]
K17216 mccA; cystathionine beta-synthase (O-acetyl-L-serine) [EC:2.5.1.134 ]
K17462 yrrT; putative AdoMet-dependent methyltransferase [EC:2.1.1.-]
K20772 ACS1_2_6; 1-aminocyclopropane-1-carboxylate synthase 1/2/6 [EC:4.4.1.14 ]
K22846 CS26; S-sulfo-L-cysteine synthase (O-acetyl-L-serine-dependent) [EC:2.5.1.144 ]
K22847 cysK2; S-sulfo-L-cysteine synthase (3-phospho-L-serine-dependent) [EC:2.8.5.1 ]
K22954 luxI; acyl homoserine lactone synthase
K22955 traI, avsI; acyl homoserine lactone synthase
K22956 expI, esaI; acyl homoserine lactone synthase
K22957 cviI; acyl homoserine lactone synthase
K22968 sinI, avsI; acyl homoserine lactone synthase
K23304 cysE; serine O-acetyltransferase
K23370 serK; L-serine kinase (ADP)
K23975 E2.8.1.16; L-aspartate semialdehyde sulfurtransferase
K23976 K23976 ; L-aspartate semialdehyde sulfurtransferase ferredoxin
K23977 GTK; L-glutamine---4-(methylsulfanyl)-2-oxobutanoate aminotransferase
K24034 SPE3-LYS9; spermidine synthase / saccharopine dehydrogenase (NADP+, L-glutamate-forming)
K24042 yitJ; methionine synthase / methylenetetrahydrofolate reductase (NADH)
K25035 rlp; S-methyl-5-thioribulose 1-phosphate isomerase
K25316 racX, ygeA; amino-acid racemase
K25317 alr, bsrV; amino-acid racemase
K27857 CGS1; plant cystathionine gamma-synthase
K28205 E2.6.1.52; phosphoserine transaminase
Compound C00019 S-Adenosyl-L-methionine
C00021 S-Adenosyl-L-homocysteine
C00441 L-Aspartate 4-semialdehyde
C01118 O-Succinyl-L-homoserine
C01137 S-Adenosylmethioninamine
C01180 4-Methylthio-2-oxobutanoic acid
C01234 1-Aminocyclopropane-1-carboxylate
C03431 S-Inosyl-L-homocysteine
C03539 S-Ribosyl-L-homocysteine
C04188 S-Methyl-5-thio-D-ribose 1-phosphate
C04582 S-Methyl-5-thio-D-ribulose 1-phosphate
C05526 S-Glutathionyl-L-cysteine
C08276 3-(Methylthio)propanoate
C11437 1-Deoxy-D-xylulose 5-phosphate
C15606 1,2-Dihydroxy-5-(methylthio)pent-1-en-3-one
C15650 2,3-Diketo-5-methylthiopentyl-1-phosphate
C15651 2-Hydroxy-3-keto-5-methylthiopentenyl-1-phosphate
C18049 N-Acyl-L-homoserine lactone
C19787 5'-S-Methyl-5'-thioinosine
C21015 gamma-L-Glutamyl-L-2-aminobutyrate
C22359 S-Methyl-1-thio-D-xylulose 5-phosphate
Reference Authors Sekowska A, Denervaud V, Ashida H, Michoud K, Haas D, Yokota A, Danchin A
Title Bacterial variations on the methionine salvage pathway.
Journal Reference Authors Ashida H, Saito Y, Kojima C, Kobayashi K, Ogasawara N, Yokota A.
Title A functional link between RuBisCO-like protein of Bacillus and photosynthetic RuBisCO.
Journal Reference Authors Sekowska A, Danchin A.
Title The methionine salvage pathway in Bacillus subtilis.
Journal Reference Authors Berger BJ, English S, Chan G, Knodel MH.
Title Methionine regeneration and aminotransferases in Bacillus subtilis, Bacillus cereus, and Bacillus anthracis.
Journal Reference Authors Goyer A, Collakova E, Shachar-Hill Y, Hanson AD
Title Functional characterization of a methionine gamma-lyase in Arabidopsis and its implication in an alternative to the reverse trans-sulfuration pathway.
Journal Reference Authors Rebeille F, Jabrin S, Bligny R, Loizeau K, Gambonnet B, Van Wilder V, Douce R, Ravanel S
Title Methionine catabolism in Arabidopsis cells is initiated by a gamma-cleavage process and leads to S-methylcysteine and isoleucine syntheses.
Journal Reference Authors Pirkov I, Norbeck J, Gustafsson L, Albers E
Title A complete inventory of all enzymes in the eukaryotic methionine salvage pathway.
Journal Reference Authors Ashida H, Saito Y, Kojima C, Yokota A
Title Enzymatic characterization of 5-methylthioribulose-1-phosphate dehydratase of the methionine salvage pathway in Bacillus subtilis.
Journal Reference Authors Kitabatake M, So MW, Tumbula DL, Soll D
Title Cysteine biosynthesis pathway in the archaeon Methanosarcina barkeri encoded by acquired bacterial genes?
Journal Reference Authors Mino K, Ishikawa K
Title Characterization of a novel thermostable O-acetylserine sulfhydrylase from Aeropyrum pernix K1.
Journal Reference Authors Tanabe S
Title Development of assay methods for endogenous inorganic sulfur compounds and sulfurtransferases and evaluation of the physiological functions of bound sulfur.
Journal Reference Authors Nishizuka Y, Seyama Y, Ikai A, Ishimura Y, Kawaguchi A (eds).
Title [Cellular Functions and Metabolic Maps] (In Japanese)
Journal Tokyo Kagaku Dojin (1997)
Reference Authors Gutierrez JA, Crowder T, Rinaldo-Matthis A, Ho MC, Almo SC, Schramm VL
Title Transition state analogs of 5'-methylthioadenosine nucleosidase disrupt quorum sensing.
Journal Related ko00010 Glycolysis / Gluconeogenesis
ko00250 Alanine, aspartate and glutamate metabolism
ko00260 Glycine, serine and threonine metabolism
ko00290 Valine, leucine and isoleucine biosynthesis
ko00430 Taurine and hypotaurine metabolism
ko00770 Pantothenate and CoA biosynthesis
ko00900 Terpenoid backbone biosynthesis
