Unusual C=C Bond Isomerization of an α,β-Unsaturated γ-Butyrolactone Catalysed by Flavoproteins from the Old Yellow Enzyme Family
نویسندگان
چکیده
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=C bond bioreduction of OYEs. This new isomerase activity enriches the catalytic versatility of ene-reductases.
منابع مشابه
Sequential Enzymatic Conversion of α‐Angelica Lactone to γ‐Valerolactone through Hydride‐Independent C=C Bond Isomerization
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عنوان ژورنال:
دوره 13 شماره
صفحات -
تاریخ انتشار 2012