The role and source of 5′‐deoxyadenosyl radical in a carbon skeleton rearrangement catalyzed by a plant enzyme

FEBS Letters

Kervio, Eric¹  Ollagnier, Sandrine¹  Rétey, János¹ 

[1] Lehrstuhl für Biochemie, Institut für Organische Chemie, Universität Karlsruhe, Kaiserstr. 12, D-76128 Karlsruhe, Germany

关键词: Tropane alkaloid;    Carbon skeleton rearrangement;    S-Adenosylmethionine as 5′-deoxyadenosyl radical donor;    SAM;    S-adenosylmethionine;   

DOI  :  10.1016/S0014-5793(98)01258-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The last step in the biosynthesis of tropane alkaloids is the carbon skeleton rearrangement of littorine to hyoscyamine. The reaction is catalyzed by a cell-free extract prepared from cultured hairy roots of Datura stramonium. Adenosylmethionine stimulated the rearrangement 10–20-fold and showed saturation kinetics with an apparent K _m of 25 μM. It is proposed that S-adenosylmethionine is the source of a 5′-deoxyadenosyl radical which initiates the rearrangement in a similar manner as it does in analogous rearrangements catalyzed by coenzyme B₁₂-dependent enzymes. Possible roles of S-adenosylmethionine as a radical source in higher plants are discussed.

【 授权许可】

Unknown