Discovering which virulence factors contribute to Streptococcus suis zoonotic infection during the host intestinal epithelium interaction

Streptococcus suis (SS) is an emerging zoonotic pathogen, which can cause meningitis  in humans and pigs. Virulent strains of SS serotype 2 (SS2) have a high propensity to infect humans whilst SS serotype 9 (SS9), most prevalent in pig SS infection, have never been isolated in human patients. The gastro-intestinal tract is a route of SS2 infection in humans and the SS adhesion to, and invasion of, host Intestinal Epithelial Cells (IEC) depends on the SS serotype and genotype. In particular, SS2 strains of genotype clonal complex (CC) CC1 and SS2 of genotype CC20 are considered zoonotic and show high affinity with human IEC, whilst SS9 strains of genotype 16 show higher interaction with pig IEC. The aim of our project is to understand which bacterial virulence factors contribute to zoonotic potential of SS. 


  1.  The expression of the most characterized virulence-related genes will be measured by quantitative PCR (qPCR) during SS2 and SS9 interaction with the IEC
  2. Generation of SS2 and SS9 SadP (streptococcal adhesin P) knock out mutants and complemented strains
  3. Analysis of the role of SadP in interaction of S. suis with human and porcine IEC in in vitro model
  4. In vitro inhibition assay of S. suis adhesion by blocking of galabiose epitope

The student(s) will get a research project from at least one of the objectives above and can participate in discussions of the medical microbiology and meningitis group meetings.

Techniques and procedures you can get acquainted with:
-     culture microbes, safely handling pathogens, generating knock-out mutants
- PCR, qPCR, biochemical assays
- cell-based assays to characterise bacterial binding to host cells

 from February 2015; preferably 4-6 months


AMC: M. Laura Ferrando, PhD / Constance Schultsz, MD PhD   /

HMI: Peter van Baarlen, PhD

Dept. of Medical Microbiology, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands