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bioRxiv · 10.1101/2021.09.22.461329

Structural Insights into Bifunctional Thaumarchaeal Crotonyl-CoA Hydratase and 3-Hydroxypropionyl-CoA Dehydratase from Nitrosopumilus maritimus

Destan, E.·Yuksel, B.·Tolar, B. B.·Ayan, E.·Deutsch, S.·Yoshikuni, Y.·Wakatsuki, S.·Francis, C. A.·DeMirci, H.
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Abstract

The ammonia-oxidizing thaumarchaeal 3-hydroxypropionate/4-hydroxybutyrate (3HP/4HB) cycle is one of the most energy-efficient CO2 fixation cycles discovered thus far. The protein encoded by Nmar_1308 (from Nitrosopumilus maritimus SCM1) is a promiscuous enzyme that catalyzes two essential reactions within the thaumarchaeal 3HP/4HB cycle, functioning as both a crotonyl-CoA hydratase (CCAH) and 3- hydroxypropionyl-CoA dehydratase (3HPD). In performing both hydratase and dehydratase activities, Nmar_1308 reduces the total number of enzymes necessary for CO2 fixation in Thaumarchaeota, reducing the overall cost for biosynthesis. Here, we present the first high-resolution crystal structure of this bifunctional enzyme with key catalytic residues in the thaumarchaeal 3HP/4HB pathway.

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Destan, E., Yuksel, B., Tolar, B. B., Ayan, E., Deutsch, S., Yoshikuni, Y., Wakatsuki, S., Francis, C. A., DeMirci, H.. 2021-09-22. Structural Insights into Bifunctional Thaumarchaeal Crotonyl-CoA Hydratase and 3-Hydroxypropionyl-CoA Dehydratase from Nitrosopumilus maritimus. https://doi.org/10.1101/2021.09.22.461329

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