title: A gel-free quantitative proteomics approach to investigate temperature adaptation of the food-borne pathogen Cronobacter turicensis 3032.
abstract: The opportunistic food-borne pathogen Cronobacter sp. causes rare but significant illness in neonates and is capable to grow at a remarkably wide range of temperatures from 5.5 to 47 degrees C. A gel-free quantitative proteomics approach was employed to investigate the molecular basis of the Cronobacter sp. adaptation to heat and cold-stress. To this end the model strain Cronobacter turicensis 3032 was grown at 25, 37, 44, and 47 degrees C, and whole-cell and secreted proteins were iTRAQ-labelled and identified/quantified by 2-D-LC-MALDI-TOF/TOF-MS. While 44 degrees C caused only minor changes in C. turicensis growth rate and protein profile, 47 degrees C affected the expression of about 20% of all 891 identified proteins and resulted in a reduced growth rate and rendered the strain non-motile and filamentous. Among the heat-induced proteins were heat shock factors, transcriptional and translational proteins, whereas proteins affecting cellular morphology, proteins involved in motility, central metabolism and energy production were down-regulated. Notably, numerous potential virulence factors were found to be up-regulated at higher temperatures, suggesting an elevated pathogenic potential of Cronobacter sp. under these growth conditions. Significant alterations in the protein expression profile and growth rate of C. turicensis exposed to 25 degrees C indicate that at this temperature the organism is cold-stressed. Up-regulated gene products comprised cold-shock, DNA-binding and ribosomal proteins, factors that support protein folding and proteins opposing cold-induced decrease in membrane fluidity, whereas down-regulated proteins were mainly involved in central metabolism.
authors: Department of Microbiology, Institute of Plant Biology, UZH, Zurich, Switzerland.
authors: Paula
authors: P
authors: Carranza
authors: Alexander
authors: A
authors: Grunau
authors: Thomas
authors: T
authors: Schneider
authors: Isabel
authors: I
authors: Hartmann
authors: Angelika
authors: A
authors: Lehner
authors: Roger
authors: R
authors: Stephan
authors: Peter
authors: P
authors: Gehrig
authors: Jonas
authors: J
authors: Grossmann
authors: Katrin
authors: K
authors: Groebel
authors: Ludwig E
authors: LE
authors: Hoelzle
authors: Leo
authors: L
authors: Eberl
authors: Kathrin
authors: K
authors: Riedel
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis / Q000235:genetics; D004755:Enterobacteriaceae / Q000235:genetics / Q000302:isolation & purification* / Q000648:ultrastructure; D005506:Food Contamination; D040901:Proteomics / Q000379:methods*; D013696:Temperature
chemical_list: D001426:Bacterial Proteins