Life Sciences Commons^™

Cj1121c, A Novel Udp-4-Keto-6-Deoxy-Glcnac C-4 Aminotransferase Essential For Protein Glycosylation And Virulence In Campylobacter Jejuni, Somalinga Vijayakumar, Alexandra Merkx-Jacques, Dinath Ratnayake, Irene Gryski, Ravinder Obhi, Sébastien Houle, Charles M Dozois, Carole Creuzenet

Alexandra Merkx-Jacques

Campylobacter jejuni produces glycoproteins that are essential for virulence. These glycoproteins carry diacetamidobacillosamine (DAB), a sugar that is not found in humans. Hence, the enzymes responsible for DAB synthesis represent potential therapeutic targets. We describe the biochemical characterization of Cj1121c, a putative aminotransferase encoded by the general protein glycosylation locus, to assess its role in DAB biosynthesis. By using overexpressed and affinity-purified enzyme, we demonstrate that Cj1121c has pyridoxal phosphate- and glutamate-dependent UDP-4-keto-6-deoxy-GlcNAc C-4 transaminase activity and produces UDP-4-amino-4,6-dideoxy-GlcNAc. This is consistent with a role in DAB biosynthesis and distinguishes Cj1121c from Cj1294, a homologous UDP-2-acetamido-2,6-dideoxy-beta-l-arabino-4-hexulose C-4 aminotransferase that we …

Splenic Endothelial Cell Lines Support Development Of Dendritic Cells From Bone Marrow, Geneviève Despars, Helen O'Neill

Helen O'Neill

Although growth factors are commonly used to generate dendritic cells (DCs) in vitro, the role of the microenvironment necessary for DC development is still poorly understood. The mixed splenic stromal cell population STX3 defines an in vitro microenvironment supportive of DC development. Dissection of cellular components of the STX3 stroma should provide information about a niche for DC development. STX3 was therefore cloned by single-cell sorting, and a panel of 102 splenic stromal cell lines was established. Four representative splenic stromal cell lines that support hematopoiesis from bone marrow are described here in terms of stromal cell type and DC …

Investigating The Glycosylation Of Groel And Its Role In The Virulence Of Campylobacter Jejuni, Alexandra Merkx-Jacques, I. Gryski, C. Creuzenet

Alexandra Merkx-Jacques

Campylobacter jejuni is a food-borne human pathogen and a major cause of gastroenteritis, reactive arthritis and neurological disorders. Due to emerging drug resistant strains, new treatments and/or vaccines need to be developed.

Protein glycosylation, or the post-translational modification of proteins by sugar molecules, plays an important role in this bacterium's virulence including affecting cell-host interactions, immunogenicity and pathogenicity. C jejuni harbours numerous proteins glycosylated by a heptasaccharide containing diacetamidobacillosamine. Our laboratory investigates the enzymes required to make this sugar as well as the glycoproteins on which this glycan is found.

Analysis of C jejuni proteins by Western blot suggests that …