2UVK

Structure of YjhT

Summary for 2UVK

• Entry DOI: 10.2210/pdb2uvk/pdb
• Descriptor: YJHT (2 entities in total)
• Functional Keywords: unknown function, hypothetical protein, sialic acid metabolism, kelch repeat, beta-propeller
• Biological source: ESCHERICHIA COLI
• Total number of polymer chains: 2
• Total formula weight: 77745.07

Authors

Muller, A.,Severi, E.,Wilson, K.S.,Thomas, G.H. (deposition date: 2007-03-12, release date: 2007-12-04, Last modification date: 2024-10-23)

Primary citation

Severi, E.,Muller, A.,Potts, J.R.,Leech, A.,Williamson, D.,Wilson, K.S.,Thomas, G.H.
Sialic Acid Mutarotation is Catalyzed by the Escherichia Coli Beta-Propeller Protein Yjht.
J.Biol.Chem., 283:4841-, 2008

PubMed Abstract: The acquisition of host-derived sialic acid is an important virulence factor for some bacterial pathogens, but in vivo this sugar acid is sequestered in sialoconjugates as the alpha-anomer. In solution, however, sialic acid is present mainly as the beta-anomer, formed by a slow spontaneous mutarotation. We studied the Escherichia coli protein YjhT as a member of a family of uncharacterized proteins present in many sialic acid-utilizing pathogens. This protein is able to accelerate the equilibration of the alpha- and beta-anomers of the sialic acid N-acetylneuraminic acid, thus describing a novel sialic acid mutarotase activity. The structure of this periplasmic protein, solved to 1.5A resolution, reveals a dimeric 6-bladed unclosed beta-propeller, the first of a bacterial Kelch domain protein. Mutagenesis of conserved residues in YjhT demonstrated an important role for Glu-209 and Arg-215 in mutarotase activity. We also present data suggesting that the ability to utilize alpha-N-acetylneuraminic acid released from complex sialoconjugates in vivo provides a physiological advantage to bacteria containing YjhT.

PubMed: 18063573
DOI: 10.1074/JBC.M707822200

Experimental method

X-RAY DIFFRACTION (1.5 Å)