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LABORATORY OF MOLECULAR BIOLOGY

- Research team - Field of activities - Work in progress - Main research tools - Publications and patents -

FIELD OF ACTIVITIES

· Our research program focuses on both fundamental and applied aspects of the molecular pathogenesis and microbial molecular diagnosis. We constructed many recombinant strains which were used to investigate the role and the regulation of the expression of various virulence factors of pathogenic Escherichia coli (septicemic, enteropathogenic and enterohaemorragic E. coli (O157:H7)), and Streptococcus suis.

· In order to study the role of selected genes in the bacterial pathogenesis, we use bacterial genetic, as well as some homologous recombination techniques.

· We develop many vaccinal tools such as recombinant strains, fusion proteins, and passive immunization systems.

· We also developed an expertise in molecular diagnosis, including identification, characterization, and molecular epidemiology of bacteria and viruses.

WORK IN PROGRESS

· Role and regulation of virulence factors of septicemic E. coli

· Paa as a new virulence factor of attaching and effacing E. coli (AEEC), including strains of O157:H7 serotype, and of enterotoxigenic E. coli (ETEC)

· Recombinant, subunitary vaccines and attenuated vectors against E. coli and S. suis

· Use of DNA chips for as a diagnostic tool and for gene expression

· Virulome of attaching and effacing E. coli

· Diagnostic tools to monitor genes related to antimicrobial resistance

MAIN RESEARCH TOOLS

• Molecular biology
• Bacterial genetic
• Recombinant proteins
• Microbiology
• DNA chips

PUBLICATIONS AND PATENTS (past 8 years)

2006-2005-2004-2003-2002-2001-2000

2006

Hamelin, K., G. Bruant, A. El-Shaarawi, S. Hill, T. A. Edge, S. Bekal, J. M. Fairbrother, J. Harel, C. Maynard, L. Masson and R. Brousseau. Occurrence of virulence and antimicrobial resistance genes in Escherichia coli from different aquatic ecosystems within the St. Clair River and Detroit River areas. Applied and Environmental Microbiology (AE) (AEM01445–06 Version “) (Accepted).

Leclerc, S., P. Boerlin, C. Gyles, J.D. Dubreuil, M. Mourez, J.M. Fairbrother and J. Harel. Paa, originally identified in attaching and effacing E. coli, is also associated with enterotoxigenic E. coli. Research in Microbiology (Accepted 2006–09–14 – res060672).

Afset, E.J., G. Bruant, R. Brousseau, J. Harel, E. Anderssen, L. Bevanger and K. Bergh. 2006. Identification of virulence genes linked with diarrhea in atypical enteropathogenic Escherichia coli (EPEC) using DNA microarray and PCR (JCM00429–06). Journal for Clinical Microbiology 44: 3703–3711.

Simpson, K. W., B. Dogan, M. Rishniw, R. E. Goldstein, S. Klaessig, P. L. McDonough, A. J. German, R. M. Yates, D. G. Russell, S. E. Johnson, D. E. Berg, J. Harel, G. Bruant, S. P. McDonough and Y. H. Schukken. 2006. Adherent and invasive Escherichia coli is associated with Granulomatous colitis in Boxer dogs. Infection and Immunity 74: 4778-4792.

Hamelin, K., G. Bruant, A. El-Shaarawi, S. Hill, T. A. Edge, S. Bekal, J. M. Fairbrother, J. Harel, C. Maynard, L. Masson and R. Brousseau. 2006. A virulence and antimicrobial resistance DNA microarray detects a high frequency of virulence genes in Escherichia coli from Great Lakes recreational waters. Applied Environmental Microbiology 72: 4200–4206.

Bruant, G., C. Maynard, S. Bekal, I. Gaucher, L. Masson, R. Brousseau and J. Harel. 2006. Development and validation of an oligonucleotide microarray for detection of multiple virulence and antimicrobial resistance genes in Escherichia coli. Applied Environmental Microbiology 72: 3780–3784.

Li, Y., G. Martinez, M. Gottschalk, S. Lacouture, P. Willson, J.D. Dubreuil, M. Jacques and J. Harel. 2006. Identification of a Surface Protein of Streptococcus suis and Evaluation of its Immunogenic and Protective Capacity in Pigs. Infection and Immunity 74: 305–312.

2005

Girard, F.; I. Batisson, G. Martinez, C. Breton, J. Harel, J.M. Fairbrother. 2005. Use of Virulence factor-specific egg yolk-derived immunoglobulins as a promising alternative to antibiotics for prevention of attaching and effacing Escherichia coli infections. FEMS Immunology & Medical Microbiology 46: 340-350.

Lemarchand, K., F. Berthiaume, C. Maynard, J. Harel, P. Payment, P. Bayardelle, L. Masson and R. Brousseau. 2005. Optimization of microbial DNA extraction and purification from raw wastewater samples for downstream pathogen detection by microarrays. Journal of Microbiological Methods 63: 107–218.

Hill, J.E., M. Gottschalk, R. J. Brousseau, J. Harel, S.M. Hemmingsen, S.H. Goh. 2005. Biochemical cpn60 and 16S rDNA sequence data indicate that Streptococcus suis serotypes 32 and 34, isolated from pigs, are Streptococcus orisratti. Veterinary Microbiology 107: 63–69.

Dauvillier, J., V. Picandet, J. Harel, M. Gottschalk, R. Desrosiers, J.P. Lavoie. 2006. Diagnostic and epidemiologic features of Lawsonia intracellularis enteropathy in 2 foals. Canadian Veterinary Journal 47: 689–691.

Maynard, C., F. Berthiaume, K. Lemarchand, J. Harel, P. Payment, P. Bayardelle, L. Masson and R. Brousseau. 2005. Waterborne pathogen detection by use of oligonucleotide–based microarrays. Applied Environmental Microbiology 71: 8548–8557.

Girard F., Oswald IP, I. Taranu, P. Hélie, G.D. Appleyard, J. Harel, and J.M. Fairbrother. 2005. Host immune status influences the development of attaching and effacing lesions in weaned pigs. Infection and Immunity 73: 5514-5523.

Girard F., I. Batisson, G. Frankel, J. Harel, and J.M. Fairbrother. 2005. Interaction of enteropathogenic and Shiga-toxin producing Escherichia coli and porcine intestinal mucosa: role of intimin and Tir in adherence. Infection and Immunity 73: 6005-6016.

Lamarche, M.G., C. M. Dozois, F. Daigle, M. Caza, R.Curtiss III, J. D. Dubreuil and J. Harel. 2005. Inactivation of the Pst system reduces the virulence of an avian pathogenic Escherichia coli O78 strain. Infection and Immunity 73: 4138–4145.

Gottschalk, M., R. Brousseau, J. Harel, S. M. Hemmingsen, S.H. Goh. 2005. Biochemical analysis, cpn60 and 16S rDNA sequence data indicate that Streptococcus suis serotypes 32 and 34, isolated from pigs, are Streptococcus orisratti. Veterinary Microbiology 107: 68–69.

2004

Berthiaume, F., Labrie, V., C. Crost, C. Martin, E.B. Newman, and J. Harel. (2004). Influence of L-leucine and L-alanine on Lrp regulation of foo coding for F1651, a Pap homologue. Journal of Bacteriology 186: 8537-8541.

Crost, C., J. Harel, F. Berthiaume, A. Garrivier, M.C. Tessier, H. Rakotoarivonina, C. Martin. (2004). Influence of environmental cues on the transcriptional regulation of foo and clp coding for F1651 and CS31A adhesins in Escherichia coli. Journal of Research in Microbiology 155: 475-482.

Dezfulian, H., D. Tremblay and J. Harel. (2004). Molecular characterization of two Pathogenicity islands in F165-positive Escherichia coli strain 4787. FEMS Microbiology Letters. 238: 321-332.

Fairbrother, J., M., J. Harel, I. Batisson, F. Girard and M.P. Guimond. (2004). International PCT. Antibodies for preventing and treating attaching and effacing E. coli (AEEC) associated diseases. Patent # US2004/0086513 A1.

Lanthier, I., M. Hébert, D. Tremblay, J. Harel, A.D. Dallaire and C. Girard. (2004). Natural West Nile virus infection in a captive juvenile Artic wolf (Canis lupus). Journal of Veterinary Diagnostic Investigation 16: 326-329.

Maynard, C, S. Bekal, F. Sanschagrin, R.C. Levesque, R. Brousseau, L. Masson, S. Larivière and J. Harel. (2004). Heterogeneity among virulence and antimicrobial resistance gene profiles of extraintestinal Escherichia coli isolates of animal and human origin. Journal of Clinical Microbiology 42: 5444-5452.

2003

Batisson, I., M.P. Guimond, F. Girard, H. An, C. Zhu, E. Oswald, J.M. Fairbrother, M. Jacques and J. Harel. (2003). Characterization of the novel factor paa involved in the early steps of the adhesion mechanism of attaching and effacing Escherichia coli. Infect. Immun. 71: 4516-25.

Bekal-Si Ali, S., R. Brouseau, L. Masson, G. Prefontaine, J. Fairbrother and J. Harel. (2003). Rapid identification of Escherichia coli pathotypes through virulence gene detection by DNA microarrays. J. Clin. Microbiol. 41 : 2113-25.

Crost, C., A. Garrivier, J. Harel and C. Martin. (2003). Leucine-Responsive Regulatory Protein-Mediated Repression of clp (Encoding CS31A) Expression by L-Leucine and L-Alanine in Escherichia coli. J. Bacteriol. 185: 1886-94.

Dezfulian, H., I. Batisson, J.M. Fairbrother, P.C.K. Lau, A. Nassar, G. Szatmari, and J. Harel. (2003). Presence and characterization of extraintestinal pathogenic E. coli virulence genes in F165-positive E. coli strains isolated from diseased calves and pigs. J. Clin. Microbiol. 41 : 1375-1385.

Fittipaldi, N., A. Broes, J. Harel, M. Kobisch and M. Gottschalk. (2003). Evaluation and field validation of PCR tests for detection of A. pleuropneumoniae in subclinically infected pigs. J. Clin. Microbiol. 41: 5085-93.

Harel J., G. Martinez, A. Nassar, H. Dezfulian, S.J. Labrie, R. Brousseau, S. Moineau and M. Gottschalk (2003). Identification of an inducible bacteriophage in a virulent strain of S.suis serotype 2. Infect. Immun. 71: 6104-08.

Maynard, C., J.M. Fairbrother, S. Bekal, F. Sanschagrin, R.C. Lévesque, R. Brousseau, L. Masson, S. Larivière and J. Harel. (2003). Antimicrobial resistance genes enterotoxigenic E.coli O149: K91 isolated from pigs over a 23-year period. Antimicrob. Agents Chemother. 47: 3214-21.

Provost, M. J. Harel, J. Labrie, M. Sirois and M. Jacques. (2003). Identification, cloning and characterization of rfaE of Actinobacillus pleuropneumoniae serotype 1, a gene involved in lipopolysaccharide inner-core biosynthesis. FEMS Microbiology Letters. 223: 7-14.

2002

Brousseau, R., J. Harel, S. Bekal, J.M. Fairbrother, L. Masson, G. Préfontaine. (2002). Provisional patent application filing. Use of Microarray to identify the pathotypes of infectious agents. No. 11293-1.December 2002.

Labrie, V., J. Harel and J.D. Dubreuil. (2002). Escherichia coli heat-stable enterotoxin b (STb) in vivo internalization within rat intestinal epithelial cells. Veterinary Research. 33 : 223-228.

Martinez, G., J. Harel, S. Lacouture and M. Gottschalk. (2002). Genetic diversity of S. suis serotypes 2 and 1/2 isolates recovered from carrier pigs in closed herds. Can. J. Vet.Res. 66 : 240-248.

Tremblay, D., J.M. Fairbrother, J. Harel. 2002. Le diagnostic moléculaire des bactéries pathogènes en médecine vétérinaire. AMMIQale 10: 52–58.

2001

Brousseau, R., J. E. Hill, G. Préfontaine, S.-H. Goh, J. Harel and S. M. Hemmingsen. (2001). Study of the variability of cpn60 genes within Streptococcus suis and correlation f the pari-wise distances between the cpn60 genes and the 16S rRNA genes. Applied and Environmental Microbiol. 60 :

Dezfulian, H., C. Crost and J. Harel. (2001). A mini review on F165 fimbriae. Recent Res. Devel. Microbiology 5 : 123-137.

Gottschalk, M., J. Harel, B. D'Amours, M. Kobisch. (2001). Provisional Application filing attenuated live vaccine against S. suis serotype 2. Ref. 10662-104USPR.

Labrie, V., H.-É. Beausoleil, J. Harel and Dubreuil (2001). Binding to sulfatide and enterotoxicity of various Escherichia coli STb mutants. Microbiology 147 : 3141-3148.

Labrie, V., J. Harel and Dubreuil (2001). Oligomerization of Escherichia coli enterotoxin b through its C-terminal hydrophobic alpha-helix. Biochimica Biophysica Acta 1535 : 128-133.

Martinez, G., J. Harel and M. Gottschalk. (2001). Specific detection by PCR of Streptococcus agalactiae in milk. Can. J. Vet. Res. 65 : 68-72.

2000

Hongyan, A., J.M. Fairbrother, C. Desautels, T. Mabrouk, D. Dugourd, H. Dezfulian and J. Harel. (2000). Presence of the LEE (locus of enterocyte effacement) in pig attaching and effacing Escherichia coli and characterization of eae, espA, espB and espD genes of PEPEC (pig EPEC) strain 1390.  Microbial Pathogenesis, 28, 291-300.

Labrie, V., H.-É. Beausoleil, J. Harel, and J.D. Dubreuil. (2000). Functional analysis of Escherichia coli STb enterotoxin binding to sulfatide using site-directed mutagenesis. In International Journal of Medical Microbiology. Eds Urban & Fischer, Vol. 290, supplement no. 30, p.A46.

Rioux, S., C. Galarneau, J. Harel, M. Kobish, J. Frey, M. Gottschalk and M. Jacques. (2000). Isolation and characterization of a capsule-deficient mutant of Actinobacillus pleuropneumoniae serotype 1. Microbial Pathogenesis, 28(5), 279-289.