Biochemical characterization of Cj 1123 c, a putative acetyltransferase & Cj 1319, a putative C6 dehydratase from Campylobacter jejuni.

Glycoproteins are important for the virulence of Campylobacter jejuni. The enzymes involved in protein glycosylation could provide new therapeutic targets. Two such proteins are Cjll23c, a putative acetyltransferase and Cj 1319, a putative GDP-mannose dehydratase encoded by the N- and O-linked protein glycosylation loci in C. jejuni, respectively. We show that Cjll23c is responsible for the synthesis of UDP- diacetamidobacillosamine. We also show that Cj 1123c can N-acetylate the O- glycosylation pathway intermediate, UDP-4-amino-4,6-dideoxy-AltNAc, accommodate different acyl donors and O-acetylate UDP-GlcNAc, thereby generating novel sugars. We demonstrate that Cj 1319 converts GDP-mannose with low conversion efficiency, suggesting that it is not the ideal substrate. We observed a buildup of a sugar-nucleotide within a Cjl319~ deficient strain that may represent the true substrate of Cj 1319. Identifying this substrate will elucidate the preferred biochemical activity of Cj 1319 and its biological role in C. jejuni. As these enzymes are involved in novel sugar biosynthesis, they could be applied as glycoengineering tools.

Name thesis:degree_name

M Sc

Discipline thesis:degree_discipline

Microbiology and Immunology

Year dc:date.issued

2008

Author dc:creator

• Demendi, Melinda

Advisors dc:contributor.advisor

• Creuzenet, Carole
• Flintoff, Wayne
• Heinrichs, David

• Campylobacter jejuni
• protein glycosylation
• acetyltransferase
• dehydratase
• Cj 1123c
• Cj 1319

Handle dc:identifier.uri

https://hdl.handle.net/20.500.14721/19415

OAI identifier oai:identifier

oai:uwo.scholaris.ca:20.500.14721/19415