Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2017

Remodelling of the Listeria monocytogenes cell surface in the adaptation to cold (#315)

MARIA GRACIELA PUCCIARELLI 1 2 , ALBERTO DIAZ-ROMERO 3 , JUAN A. AYALA 2 , MIGUEL A. DE PEDRO 2 , FRANCISCO GARCIA DEL PORTILLO 3
  1. Department of Molecular Biology, Universidad Autónoma de Madrid, Madrid, Spain
  2. Centre for Molecular Biology "Severo Ochoa" (CBMSO)-CSIC, Madrid, Spain
  3. Laboratory of Intracellular Bacterial Pathogens, National Centre for Biotechnology (CNB)-CSIC, Madrid, Spain

Listeria monocytogenes is an intracellular bacterial pathogen that crosses host defence barriers such as the intestinal epithelium, the placenta and the blood-brain barrier in humans and domestic animals. A main factor that contributes to the spread of this pathogen in the food industry is its capacity to growth at refrigeration (4ºC) temperatures. Using highly sensitive non-gel proteomic techniques, we have dissected the cell wall subproteome of L. monocytogenes during growth at 4ºC. A few surface proteins covalently bound to peptidoglycan were found to be up-regulated by cold. These observations were confirmed by immunoassays in peptidoglycan extracts prepared from bacterial cultures grown at 37ºC and 4ºC.  We have also collected RNASeq data at 4ºC that point to defined small-RNAs with a potential regulatory action in genes encoding some of these surface proteins. Two additional aspects we are investigating include the intervention of cold-shock proteins (Csp) in the regulation of these surface proteins and, the analysis of peptidoglycan structural changes taking part at 4ºC. Our data indicate that both factors also play a fundamental role in the remodelling of L. monocytogenes cell surface at low temperature.