Download MendeleyStructural analysis of the pseudaminic acid synthase PseI from Campylobacter jejuni.
Song, W.S., Park, M.A., Ki, D.U., Yoon, S.I.(2022) Biochem Biophys Res Commun 635: 252-258
- PubMed: 36283338
- DOI: https://doi.org/10.1016/j.bbrc.2022.10.050
- Primary Citation of Related Structures:
8H2C - PubMed Abstract:
Campylobacter jejuni PseI is a pseudaminic acid synthase that condenses the 2,4-diacetamido-2,4,6-trideoxy-l-altrose sugar (6-deoxy AltdiNAc) and phosphoenolpyruvate to generate pseudaminic acid, a sialic acid-like 9-carbon backbone α-keto sugar. Pseudaminic acid is conjugated to cell surface proteins and lipids and plays a key role in the mobility and virulence of C. jejuni and other pathogenic bacteria. To provide insights into the catalytic mechanism of PseI, we performed a structural study on PseI. PseI forms a two-domain structure and assembles into a domain-swapped homodimer. The PseI dimer has two cavities, each of which accommodates a metal ion using conserved histidine residues. A comparative analysis of structures and sequences suggests that the cavity of PseI functions as an active site that binds the 6-deoxy AltdiNAc and phosphoenolpyruvate substrates and mediates their condensation. Furthermore, we propose the substrate binding-induced structural rearrangement of PseI and predict 6-deoxy AltdiNAc recognition residues that are specific to PseI.
Organizational Affiliation:
Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, 24341, Republic of Korea. Electronic address: bioticsong@gmail.com.
