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Unusual C=C bond isomerization of an ?,?-unsaturated ?-butyrolactone catalysed by flavoproteins from the old yellow enzyme family.

ABSTRACT: An unexpected, redox-neutral C=C bond isomerization of a ?-butyrolactone bearing an exo-methylene unit to the thermodynamically more favoured endo isomer (k(cat) =0.076 s(-1) ) catalysed by flavoproteins from the Old Yellow Enzyme family was discovered. Theoretical calculations and kinetic data support a mechanism through which the isomerization proceeds through FMN-mediated hydride addition onto exo-C?, followed by hydride abstraction from endo-C?', which is in line with the well-established C=C bond bioreduction of OYEs. This new isomerase activity enriches the catalytic versatility of ene-reductases.

SUBMITTER: Durchschein K

PROVIDER: S-EPMC3533789 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Unusual C=C bond isomerization of an α,β-unsaturated γ-butyrolactone catalysed by flavoproteins from the old yellow enzyme family.

Durchschein Katharina K Wallner Silvia S Macheroux Peter P Zangger Klaus K Fabian Walter M F WM Faber Kurt K

Chembiochem : a European journal of chemical biology 20120928 16

An unexpected, redox-neutral C=C bond isomerization of a γ-butyrolactone bearing an exo-methylene unit to the thermodynamically more favoured endo isomer (k(cat) =0.076 s(-1) ) catalysed by flavoproteins from the Old Yellow Enzyme family was discovered. Theoretical calculations and kinetic data support a mechanism through which the isomerization proceeds through FMN-mediated hydride addition onto exo-Cβ, followed by hydride abstraction from endo-Cβ', which is in line with the well-established C= ...[more]

PMID: 23024004

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