IntEnz

EC 4.3.99.3 - 7-carboxy-7-deazaguanine synthase

IntEnz Enzyme Nomenclature
EC 4.3.99.3

Names

Reaction

• 27974 [IUBMB]
  6-carboxy-5,6,7,8-tetrahydropterin

  6-carboxy-5,6,7,8-tetrahydropterin

  Name origin: UniProt - CHECKED (C)

  CHEBI:61032

  Formula: C7H8N5O3
  Charge: -1

  ChEBI compound status: CHECKED (C)

  

  +

  H⁺

  H(+)

  Name origin: UniProt - CHECKED (C)

  CHEBI:15378

  Formula: H
  Charge: 1

  ChEBI compound status: CHECKED (C)

  

  =

  7-carboxy-7-deazaguanine

  7-carboxy-7-deazaguanine

  Name origin: UniProt - CHECKED (C)

  CHEBI:61036

  Formula: C7H5N4O3
  Charge: -1

  ChEBI compound status: CHECKED (C)

  

  +

  NH₄⁺

  NH4(+)

  Name origin: UniProt - CHECKED (C)

  CHEBI:28938

  Formula: H4N
  Charge: 1

  ChEBI compound status: CHECKED (C)

  

Cofactors

• Mg²⁺
• S-adenosyl-L-methionine
• iron-sulfur

Comments:

Requires Mg2+. The enzyme is a member of the superfamily of S-adenosyl-L-methionine-dependent radical (radical AdoMet) enzymes. Binds a [4Fe-4S] cluster that is coordinated by 3 cysteines and an exchangeable S-adenosyl-L-methionine molecule. The S-adenosyl-L-methionine is catalytic as it is regenerated at the end of the reaction. The reaction is part of the biosynthesis pathway of queuosine.

Links to other databases

References

1. McCarty, R. M., Somogyi, A., Lin, G., Jacobsen, N. E., Bandarian, V.
   The deazapurine biosynthetic pathway revealed: in vitro enzymatic synthesis of PreQ(0) from guanosine 5'-triphosphate in four steps.
   Biochemistry 48 : 3847-3852 (2009). [PMID: 19354300]

[EC 4.3.99.3 created 2012]