Identification and role of a 6-deoxy-4-keto-hexosamine in the lipopolysaccharide outer core of Yersinia enterocolitica serotype O:3.
The outer core (OC) region of Yersinia enterocolitica serotype O:3 lipopolysaccharide is a hexasaccharide essential for the integrity of the outer membrane. It is involved in resistance against cationic antimicrobial peptides and plays a role in virulence during early phases of infection. We show here that the proximal residue of the OC hexasaccharide is a rarely encountered 4-keto-hexosamine, 2-acetamido-2,6-dideoxy-D-xylo-hex-4-ulopyranose (Sugp) and that WbcP is a UDP-GlcNAc-4,6-dehydratase enzyme responsible for the biosynthesis of the nucleotide-activated form of this rare sugar converting UDP-2-acetamido-2-deoxy-D-glucopyranose (UDP-D-GlcpNAc) to UDP-2-acetamido-2,6-dideoxy-D-xylo-hex-4-ulopyranose (UDP- Sugp). In an aqueous environment, the 4-keto group of this sugar was present in the 4-dihydroxy form, due to hydration. Furthermore, evidence is provided that the axial 4-hydroxy group of this dihydroxy function was crucial for the biological role of the OC, that is, in the bacteriophage and enterocoliticin receptor structure and in the epitope of a monoclonal antibody.
Pinta
Elise
E
Infection Biology Research Program, Haartman Institute, Department of Bacteriology and Immunology, P.O.Box 21 (Haartmaninkatu 3), 00014 University of Helsinki, Finland.
Duda
Katarzyna A
KA
Hanuszkiewicz
Anna
A
Kaczyński
Zbigniew
Z
Lindner
Buko
B
Miller
Wayne L
WL
Hyytiäinen
Heidi
H
Vogel
Christian
C
Borowski
Sabine
S
Kasperkiewicz
Katarzyna
K
Lam
Joseph S
JS
Radziejewska-Lebrecht
Joanna
J
Skurnik
Mikael
M
Holst
Otto
O
D001426:Bacterial Proteins / Q000378:metabolism; D019075:Electrophoresis, Capillary; D006595:Hexosamines / Q000096:biosynthesis / Q000737:chemistry / Q000502:physiology*; D008070:Lipopolysaccharides / Q000737:chemistry*; D012703:Serotyping; D015008:Yersinia enterocolitica / Q000737:chemistry*
D001426:Bacterial Proteins; D006595:Hexosamines; D008070:Lipopolysaccharides