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Methionine synthase

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This is a complex reaction as the product, tetrahydrofolate, is a poor leaving group, thus requiring a "supernucleophile" with a protein-bound B-12 vitamin Cobalamin as the methyl carrier.
This is a complex reaction as the product, tetrahydrofolate, is a poor leaving group, thus requiring a "supernucleophile" with a protein-bound B-12 vitamin Cobalamin as the methyl carrier.
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== Structural highlights ==
== Structural highlights ==
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Methionine synthase (MetH) is a B12-dependent enzyme that methylates homocysteine to regenerate methionine. The <scene name='90/907471/Superposition_1/2'>full structure of MetH</scene> has yet to be determined but we understand it contains 4 domains of B12 cobalamin (in pink), methyltetrahydrofolate (blue), homocysteine (yellow), and SAH (as part of the SAM cycle; in red). Each domain with an important function required for catalytic and reactivation cycles.
Methionine synthase (MetH) is a B12-dependent enzyme that methylates homocysteine to regenerate methionine. The <scene name='90/907471/Superposition_1/2'>full structure of MetH</scene> has yet to be determined but we understand it contains 4 domains of B12 cobalamin (in pink), methyltetrahydrofolate (blue), homocysteine (yellow), and SAH (as part of the SAM cycle; in red). Each domain with an important function required for catalytic and reactivation cycles.
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</StructureSection>
== Vitamin B-12 ==
== Vitamin B-12 ==
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Methionine deficiency can result in diseases such as birth abnormalities.
Methionine deficiency can result in diseases such as birth abnormalities.
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</StructureSection>
 
== References ==
== References ==

Revision as of 18:38, 5 April 2022

Contents

Methionine synthase

B-12 dependent fragment of E. coli methionine synthase with Cobalt (in pink)

Drag the structure with the mouse to rotate

Vitamin B-12

Oxidation States of Cobalamin

Co(I) - active, unstable, high energy

Co(II) - common oxidation state

Relevance

Methionine deficiency can result in diseases such as birth abnormalities.

References

[1]

  1. Barra L, Fontenelle C, Ermel G, Trautwetter A, Walker GC, Blanco C. Interrelations between glycine betaine catabolism and methionine biosynthesis in Sinorhizobium meliloti strain 102F34. J Bacteriol. 2006 Oct;188(20):7195-204. doi: 10.1128/JB.00208-06. PMID:17015658 doi:http://dx.doi.org/10.1128/JB.00208-06

Proteopedia Page Contributors and Editors (what is this?)

Kia Yang, Karsten Theis, Michal Harel, Anna Postnikova, Michael O'Shaughnessy

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