title: Quantitative analysis of Streptococcus pneumoniae TIGR4 response to in vitro iron restriction by 2-D LC ESI MS/MS.
abstract: Understanding the growth of bacterial pathogens in a micronutrient restricted host environment can identify potential virulence proteins that help overcome this nutritional barrier to productive infection. In this study, we investigated the pneumococcal protein expression response to iron limitation using an in vitro model. We identified S. pneumoniae TIGR4 proteins by 2-D LC ESI MS/MS and determined significant changes in protein expression in response to iron restriction using computer-intensive random resampling methods. Differential protein expression was studied in the context of a S. pneumoniae TIGR4 protein interaction network using Pathway Studio. Our analysis showed that pneumococcal iron restriction response was marked by increased expression of known virulence factors like PsaA. It involved changes in the expression of stress response, and phase variation and biofilm formation proteins. The net effect of changes in all these biological processes could increase the virulence of S. pneumoniae TIGR4 during in vivo infection.
authors.affiliation: College of Veterinary Medicine, Mississippi State University, MS 39762, USA. bnanduri@cvm.msstate.edu
authors.forename: Bindu
authors.initials: B
authors.lastname: Nanduri
authors.forename: Pratik
authors.initials: P
authors.lastname: Shah
authors.forename: Mahalingam
authors.initials: M
authors.lastname: Ramkumar
authors.forename: Edward B
authors.initials: EB
authors.lastname: Allen
authors.forename: Edwin
authors.initials: E
authors.lastname: Swiatlo
authors.forename: Shane C
authors.initials: SC
authors.lastname: Burgess
authors.forename: Mark L
authors.initials: ML
authors.lastname: Lawrence
mesh_terms: D018829:Adhesins, Bacterial / Q000032:analysis / Q000378:metabolism; D001426:Bacterial Proteins / Q000032:analysis* / Q000378:metabolism; D002853:Chromatography, Liquid / Q000379:methods*; D007501:Iron / Q000378:metabolism* / Q000494:pharmacology; D008074:Lipoproteins / Q000032:analysis / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013296:Streptococcus pneumoniae / Q000187:drug effects / Q000378:metabolism*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D018829:Adhesins, Bacterial; D001426:Bacterial Proteins; D008074:Lipoproteins; C085000:PsaA protein, Streptococcus; D007501:Iron