8h2c

Publication Abstract from PubMed

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 alpha-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.

Structural analysis of the pseudaminic acid synthase PseI from Campylobacter jejuni.,Song WS, Park MA, Ki DU, Yoon SI Biochem Biophys Res Commun. 2022 Oct 17;635:252-258. doi:, 10.1016/j.bbrc.2022.10.050. PMID:36283338^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.