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Catalysis of a new ribose carbon-insertion reaction by the molybdenum cofactor biosynthetic enzyme MoaA.

ABSTRACT: MoaA, a radical S-adenosylmethionine enzyme, catalyzes the first step in molybdopterin biosynthesis. This reaction involves a complex rearrangement in which C8 of guanosine triphosphate is inserted between C2' and C3' of the ribose. This study identifies the site of initial hydrogen atom abstraction by the adenosyl radical and advances a mechanistic proposal for this unprecedented reaction.

SUBMITTER: Mehta AP

PROVIDER: S-EPMC3582411 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Catalysis of a new ribose carbon-insertion reaction by the molybdenum cofactor biosynthetic enzyme MoaA.

Mehta Angad P AP Hanes Jeremiah W JW Abdelwahed Sameh H SH Hilmey David G DG Hänzelmann Petra P Begley Tadhg P TP

Biochemistry 20130204 7

MoaA, a radical S-adenosylmethionine enzyme, catalyzes the first step in molybdopterin biosynthesis. This reaction involves a complex rearrangement in which C8 of guanosine triphosphate is inserted between C2' and C3' of the ribose. This study identifies the site of initial hydrogen atom abstraction by the adenosyl radical and advances a mechanistic proposal for this unprecedented reaction. ...[more]

PMID: 23286307

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