cardiology-congress-microbe-infection-2018-posters

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J u l y 2 3 - 2 4 , 2 0 1 8 | R o m e , I t a l y

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allied

academies

Joint Event on

Cardiology Congress 2018 & Microbe Infection 2018

Biomedical Research

ISSN: 0976-1683

Volume 29

World Congress on

CARDIOLOGY

MICROBIOLOGY AND MICROBIAL INFECTION

Annual Congress on

Carole Creuzenet, Biomed Res 2018, Volume 29 | DOI: 10.4066/biomedicalresearch-C1-003

CAPSULAR HEPTOSE SYNTHESIS

PATHWAY OF

CAMPYLOBACTER JEJUNI

AS A NEW TARGET TO PREVENT

CAMPYLOBACTERIOSIS

Carole Creuzenet

The University of Western Ontario, Canada

ampylobacter jejuni

(CJ) is a commensal in poultry but is also a human

bacterial pathogen. It is a predominant cause of bacterial enteritis

worldwide and, in developed countries, campylobacteriosis is associated with

consumption of undercooked poultry meat that had been contaminated by

CJ during slaughter. CJ’s capsule is an external polysaccharide important for

colonization and virulence that comprises a modified heptose in most strains.

We investigate the biological roles and the biosynthetic pathways of these

heptoseswith a view to inhibit their synthesis in poultry before slaughter, which

would decrease the CJ load in poultry meat and prevent harmful transmission

to humans. We deciphered the activity of seven enzymes involved in modified

heptoses synthesis in two CJ strains, revealing unexpected functions and

specificities of novel C3/C5 epimerases and C4 reductases that could be

targeted for inhibition. Knockout mutagenesis studies of heptose modifying

genes in strain NCTC 11168 showed that heptose modification is not

necessary for capsule synthesis but affects bacterial resistance to serum

and bile salts, biofilm formation, adhesion to intestinal epithelial cells and

their invasion. The mutants also showed slightly decreased phagocytosis

by macrophages. Most importantly, we also demonstrate that heptose

modifying genes are important for colonization and persistence of

C. jejuni

in chicken. These findings suggest that fine tuning the capsule composition

via heptose modification contributes to host pathogen interactions and

likely host specificity. This work also provides new enzyme targets to

screen for inhibitors that could be used to decrease campylobacteriosis by

application to chickens pre-slaughter. It also provides new tools to synthesize

carbohydrate antigens useful for chicken vaccination and provides grounds

for the elucidation of similar pathways of other pathogens.

Carole Creuzenet has completed her PhD in Biochem-

istry at the University of Nantes and the National In-

stitute for Agronomical Research (France) and her

postdoctoral studies at the Massachusetts Institute

of Technology (USA) and the University of Guelph

(Canada). She is Associate Professor at the University

of Western Ontario (London, Canada) where her lab

focuses on virulence factors from bacterial gastroin-

testinal pathogens such as

Campylobacter jejuni, He-

licobacter pylori and Yersinia pseudotuberculosis

. Her

focus is on glycolipids and glycoproteins as well as

on novel secreted proteins and their folding partners.

She has published 38 papers in reputed journals with

h-index of 19.

ccreuzen@uwo.ca

BIOGRAPHY