View source for 7,8-didemethyl-8-hydroxy-5-deazariboflavin synthase

{{Short description|Class of enzymes}}
{{Infobox enzyme
| Name = 7,8-didemethyl-8-hydroxy-5-deazariboflavin synthase (CofG)
| EC_number = 4.3.1.32
| CAS_number =
| GO_code = 0044689
| image =
| width =
| caption =
}}
{{Infobox enzyme
| Name= 5-amino-6-(D-ribitylamino)uracil--L-tyrosine 4-hydroxyphenyl transferase (CofH)
| EC_number = 2.5.1.147
}}
'''7,8-didemethyl-8-hydroxy-5-deazariboflavin synthase''' ({{EC number|4.3.1.32}}, ''FO synthase'') and '''5-amino-6-(D-ribitylamino)uracil—L-tyrosine 4-hydroxyphenyl transferase''' ({{EC number|2.5.1.147}}) are two [[enzyme]]s always complexed together to achieve synthesis of FO, a precursor to [[Coenzyme F420]]. Their [[List of enzymes|systematic name]]s are ''5-amino-5-(4-hydroxybenzyl)-6-(D-ribitylimino)-5,6-dihydrouracil ammonia-lyase (7,8-didemethyl-8-hydroxy-5-deazariboflavin-forming)'' and ''5-amino-6-(D-ribitylamino)uracil:L-tyrosine, 4-hydroxyphenyl transferase'' respectively.<ref>{{cite journal | vauthors = Graham DE, Xu H, White RH | title = Identification of the 7,8-didemethyl-8-hydroxy-5-deazariboflavin synthase required for coenzyme F(420) biosynthesis | journal = Archives of Microbiology | volume = 180 | issue = 6 | pages = 455–64 | date = December 2003 | pmid = 14593448 | doi = 10.1007/s00203-003-0614-8 }}</ref><ref>{{cite journal | vauthors = Choi KP, Kendrick N, Daniels L | title = Demonstration that fbiC is required by Mycobacterium bovis BCG for coenzyme F(420) and FO biosynthesis | journal = Journal of Bacteriology | volume = 184 | issue = 9 | pages = 2420–8 | date = May 2002 | pmid = 11948155 | pmc = 134996 | doi = 10.1128/JB.184.9.2420-2428.2002 }}</ref> The enzymes [[catalysis|catalyse]] the following [[chemical reaction]]s:
: (2.5.1.147) 5-amino-6-(D-ribitylamino)uracil + L-[[tyrosine]] + [[S-adenosyl-L-methionine]] = 5-amino-5-(4-hydroxybenzyl)-6-(D-ribitylimino)-5,6-dihydrouracil + 2-iminoacetate + L-[[methionine]] + 5'-deoxyadenosin
: (4.3.1.32) 5-amino-5-(4-hydroxybenzyl)-6-(D-ribitylimino)-5,6-dihydrouracil + S-adenosyl-L-methionine = 7,8-didemethyl-8-hydroxy-5-deazariboflavin + NH<sub>3</sub> + L-methionine + 5'-deoxyadenosine
Enzyme 2.5.1.147 binds a 4Fe-4S cluster. The condensation reaction is initiated by the 5'-deoxyadenosyl radical. The complex was formerly named as a single entity under {{EC number|2.5.1.77}}.
{{Pfam box|Name=CofG|Symbol=CofG|InterPro=IPR019939}}
{{Pfam box|Name=CofH|Symbol=CofH|InterPro=IPR019940}}
All members of these enzymes belong to a single clade of the CofH (2.5.1.147) and CofG (4.3.1.32) families, sharing a [[TIM barrel]] structure. The two EC numbers represent discrete steps in this reaction. Some enzyme complexes have CofG and CofH (subunits 1 and 2) in different chains assembled into a heterodimer, while others like the bifunctional ''fbiC'' has the two domains on one single chain.
== References ==
{{reflist}}
== External links ==
*{{MeshName|7,8-didemethyl-8-hydroxy-5-deazariboflavin+synthase}}
{{Alkyl and aryl transferases}}
{{Enzymes}}
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[[Category:EC 2.5.1]]