Structural Insight into Substrate Specificity of 3-Hydroxypropionyl-Coenzyme A Dehydratase from Metallosphaera sedula
Lee, D., Kim, K.J.(2018) Sci Rep 8: 10692-10692
- PubMed: 30013155 
- DOI: https://doi.org/10.1038/s41598-018-29070-w
- Primary Citation of Related Structures:  
5ZAI - PubMed Abstract: 
Metallosphaera sedula is a thermoacidophilic autotrophic archaeon known to utilize the 3-hydroxypropionate/4-hydroxybutyrate cycle (3-HP/4-HB cycle) as carbon fixation pathway. 3-Hydroxypropionyl-CoA dehydratase (3HPCD) is an enzyme involved in the 3-HP/4-HB cycle by converting 3-hydroxypropionyl-CoA to acryloyl-CoA. To elucidate the molecular mechanism of 3HPCD from M. sedula (Ms3HPCD), we determined its crystal structure in complex with Coenzyme A (CoA). Ms3HPCD showed an overall structure and the CoA-binding mode similar to other enoyl-CoA hydratase (ECH) family enzymes. However, compared with the other ECHs, Ms3HPCD has a tightly formed α3 helix near the active site, and bulky aromatic residues are located at the enoyl-group binding site, resulting in the enzyme having an optimal substrate binding site for accepting short-chain 3-hydroxyacyl-CoA as a substrate. Moreover, based on the phylogenetic tree analysis, we propose that the 3HPCD homologues from the phylum Crenarchaeota have an enoyl-group binding pocket similar to that of bacterial short-chain ECHs.
Organizational Affiliation: 
KNU Creative BioResearch Group, School of Life Sciences and Biotechnology, Kyungpook National University, Daegu, 41566, Republic of Korea.