In by admin

NameMr. Justin Ellenburg
Organization or InstitutionUniversity of Florida
TopicMass Spectrometry

Imaging Mass Spectrometry of sulfur containing metabolites in a model of systemic Staphylococcus aureus infection



Justin M. Ellenburg1, Joshua Lensmire2, Paige Kies2, Neal D. Hammer2, Boone M. Prentice1

Author Institution(s)

1 Department of Chemistry, University of Florida, Gainesville FL, USA
2 Department of Microbiology & Molecular Genetics, Michigan State University, East Lansing MI, USA


Bacterial pathogens are known to scavenge transition metals and other essential nutrients from their host to meet nutritional needs. Sulfur, being a macronutrient for both bacteria and host, is readily available in host cells and necessary for the proliferation of pathogens, making it a likely candidate for nutrient scavenging. Staphylococcus aureus has been implicated in sulfur scavenging of organosulfur metabolites like glutathione (GSH) , however, direct evidence of sulfur scavenging has been lacking. Studies typically focus on identifying metabolite pathways and the roles that various enzymes play in sulfur metabolism and pathogen proliferation, but in vivo or in situ studies have not been performed. Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) allows for label-free mapping of a variety of sulfur containing metabolites in pathogen infected tissues, providing evidence of in situ sulfur scavenging. Herein, we have prepared thin tissue section from infect organs using a Leica cryostat which are sublimated with a 9-aminoacridine MALDI matrix prior to IMS analysis. Our preliminary data from S. aureus infected rat kidneys shows localization of GSH to infectious foci (i.e. tissue abscesses) while oxidized homocysteine is present in infected tissue but absent from abscesses.