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Your query returned 5 entries. Printable version
EC | 1.14.19.59 | ||||||||
Accepted name: | tryptophan 6-halogenase | ||||||||
Reaction: | (1) L-tryptophan + FADH2 + chloride + O2 + H+ = 6-chloro-L-tryptophan + FAD + 2 H2O (2) D-tryptophan + FADH2 + chloride + O2 + H+ = 6-chloro-D-tryptophan + FAD + 2 H2O |
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For diagram of chlorotryptophan biosynthesis, click here | |||||||||
Other name(s): | sttH (gene name); thdH (gene name) | ||||||||
Systematic name: | L-tryptophan:FADH2 oxidoreductase (6-halogenating) | ||||||||
Comments: | The enzyme is a flavin-dependent halogenase that has been described from several bacterial species. It utilizes molecular oxygen to oxidize the FADH2 cofactor, giving C4a-hydroperoxyflavin, which then reacts with chloride to produce a hypochlorite ion. The latter reacts with an active site lysine to generate a chloramine, which chlorinates the substrate. cf. EC 1.14.19.58, tryptophan 5-halogenase, and EC 1.14.19.9, tryptophan 7-halogenase. | ||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||||
References: |
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EC | 1.14.19.76 | ||||||||
Accepted name: | flavone synthase II | ||||||||
Reaction: | a flavanone + [reduced NADPH—hemoprotein reductase] + O2 = a flavone + [oxidized NADPH—hemoprotein reductase] + 2 H2O | ||||||||
Other name(s): | CYP93B16 (gene name); CYP93G1 (gene name); FNS II | ||||||||
Systematic name: | flavanone,[reduced NADPH—hemoprotein reductase]:oxygen oxidoreductase (flavone-forming) | ||||||||
Comments: | A cytochrome P-450 (heme-thiolate) protein found in plants. The rice enzyme channels flavanones to the biosynthesis of tricin O-linked conjugates. cf. EC 1.14.20.5, flavone synthase I. | ||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||||
References: |
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EC | 1.14.99.47 | ||||||||
Accepted name: | (+)-larreatricin hydroxylase | ||||||||
Reaction: | (+)-larreatricin + reduced acceptor + O2 = (+)-3′-hydroxylarreatricin + acceptor + H2O | ||||||||
Glossary: | (+)-larreatricin = 4,4′-[(2R,3R,4S,5R)-3,4-dimethyltetrahydrofuran-2,5-diyl]bisphenol | ||||||||
Systematic name: | (+)-larreatricin:oxygen 3′-hydroxylase | ||||||||
Comments: | Isolated from the plant Larrea tridentata (creosote bush). The enzyme has a strong preference for the 3′ position of (+)-larreatricin. | ||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||||
References: |
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EC | 2.1.1.175 | ||||||||
Accepted name: | tricin synthase | ||||||||
Reaction: | 2 S-adenosyl-L-methionine + tricetin = 2 S-adenosyl-L-homocysteine + 3′,5′-O-dimethyltricetin (overall reaction) (1a) S-adenosyl-L-methionine + tricetin = S-adenosyl-L-homocysteine + 3′-O-methyltricetin (1b) S-adenosyl-L-methionine + 3′-O-methyltricetin = S-adenosyl-L-homocysteine + 3′,5′-O-dimethyltricetin |
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Glossary: | tricin = 3′,5′-O-dimethyltricetin | ||||||||
Other name(s): | ROMT-17; ROMT-15; HvOMT1; ZmOMT1 | ||||||||
Systematic name: | S-adenosyl-L-methionine:tricetin 3′,5′-O-dimethyltransferase | ||||||||
Comments: | The enzymes from Oryza sativa (ROMT-15 and ROMT-17) catalyses the stepwise methylation of tricetin to its 3′-mono- and 3′,5′-dimethyl ethers. In contrast with the wheat enzyme (EC 2.1.1.169, tricetin 3′,4′,5′-O-trimethyltransferase), tricetin dimethyl ether is not converted to its 3′,4′,5′-trimethylated ether derivative [1]. The enzymes from Hordeum vulgare (HvOMT1) and from Zea mays (ZmOMT1) form the 3′,5′-dimethyl derivative as the major product [2]. | ||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||||
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EC | 2.1.1.390 | ||||||||
Accepted name: | gentamicin X2 methyltransferase | ||||||||
Reaction: | gentamicin X2 + 2 S-adenosyl-L-methionine + reduced acceptor = geneticin + 5′-deoxyadenosine + L-methionine + S-adenosyl-L-homocysteine + oxidized acceptor (overall reaction) (1a) S-adenosyl-L-methionine + cob(I)alamin = S-adenosyl-L-homocysteine + methylcob(III)alamin (1b) methylcob(III)alamin + gentamicin X2 + S-adenosyl-L-methionine = cob(III)alamin + geneticin + 5′-deoxyadenosine + L-methionine (1c) cob(III)alamin + reduced acceptor = cob(I)alamin + oxidized acceptor |
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Glossary: | geneticin = G418 = (1R,2S,3S,4R,6S)-4,6-diamino-3-{[3-deoxy-4-C-methyl-3-(methylamino)-β-L-arabinopyranosyl]oxy}-2-hydroxycyclohexyl 2-amino-2,7-dideoxy-D-glycero-α-D-gluco-heptopyranoside | ||||||||
Other name(s): | genK (gene name); gntK (gene name); gentamicin C-methyltransferase (ambiguous) | ||||||||
Systematic name: | S-adenosyl-L-methionine:gentamicin X2 C6′-methyltransferase | ||||||||
Comments: | The enzyme, isolated from the bacterium Micromonospora echinospora, has a single [4Fe-4S] cluster per monomer. It is a radical S-adenosyl-L-methionine (SAM) enzyme with a methylcob(III)alamin cofactor. The enzyme uses two molecues of SAM for the reaction. One molecule forms a 5′-deoxyadenosyl radical, while the other is used to methylate the cobalamin cofactor. It catalyses methylation of the 6′-carbon of gentamicin X2 (GenX2) to produce genetricin (G418) during the biosynthesis of gentamicins. The 6′-pro-R-hydrogen atom of GenX2 is stereoselectively abstracted by the 5′-deoxyadenosyl radical and methylation occurs with retention of configuration at C6′. The regeneration of cob(I)alamin from cob(III)alamin is carried out with an as yet unidentified electron donor. | ||||||||
Links to other databases: | BRENDA, EXPASY, KEGG, MetaCyc | ||||||||
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