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Title: Targeted Protein Degradation by Salmonella under Phagosome-Mimicking Culture Conditions Investigated Using Comparative Peptidomics

Abstract

The pathogen Salmonella enterica is known to cause both food poisoning and typhoid fever. Due to the emergence of antibiotic-resistant isolates and the threat of bioterrorism (e.g., contamination of the food supply), there is a growing need to study this bacterium. In this investigation, comparative peptidomics was used to study Salmonella enterica serovar Typhimurium cultured in either a rich medium or in an acidic, low magnesium, and minimal nutrient medium designed to roughly mimic the macrophage phagosomal compartment (within which Salmonella are known to survive). Native peptides from cleared cell lysates were enriched by using isopropanol extraction and analyzed by using both LC-MS/MS and LC-FTICR-MS. We identified 5,163 distinct peptides originating from 682 proteins and the data clearly indicated that compared to cells cultured in the rich medium, Salmonella cultured in the phagosome-mimicking medium had dramatically higher abundances of a wide variety of protein degradation products, especially from ribosomal proteins. Salmonella from the same cultures were also analyzed by using bottom-up proteomics, and when the peptidomic and proteomic data were analyzed together, two clusters of proteins targeted for proteolysis were tentatively identified. Possible roles of targeted proteolysis by phagocytosed Salmonella are discussed.

Authors:
; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
912500
Report Number(s):
PNNL-SA-50929
10904; 400412000; TRN: US200801%%1054
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Molecular & Cellular Proteomics. MCP, 6(4):717-727; Journal Volume: 6; Journal Issue: 4
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; COMPARTMENTS; CONTAMINATION; FEVER; FOOD; MACROPHAGES; MAGNESIUM; NUTRIENTS; PATHOGENS; PEPTIDES; POISONING; PROTEINS; PROTEOLYSIS; SALMONELLA; TYPHOID; Salmonella typhimurium, peptidomics, proteomics, mass spectrometry, FTICR, SEQUEST®; Environmental Molecular Sciences Laboratory

Citation Formats

Manes, Nathan P., Gustin, Jean K., Rue, Joanne, Mottaz, Heather M., Purvine, Samuel O., Norbeck, Angela D., Monroe, Matthew E., Zimmer, Jennifer S., Metz, Thomas O., Adkins, Joshua N., Smith, Richard D., and Heffron, Fred. Targeted Protein Degradation by Salmonella under Phagosome-Mimicking Culture Conditions Investigated Using Comparative Peptidomics. United States: N. p., 2007. Web. doi:10.1074/mcp.M600282-MCP200.
Manes, Nathan P., Gustin, Jean K., Rue, Joanne, Mottaz, Heather M., Purvine, Samuel O., Norbeck, Angela D., Monroe, Matthew E., Zimmer, Jennifer S., Metz, Thomas O., Adkins, Joshua N., Smith, Richard D., & Heffron, Fred. Targeted Protein Degradation by Salmonella under Phagosome-Mimicking Culture Conditions Investigated Using Comparative Peptidomics. United States. doi:10.1074/mcp.M600282-MCP200.
Manes, Nathan P., Gustin, Jean K., Rue, Joanne, Mottaz, Heather M., Purvine, Samuel O., Norbeck, Angela D., Monroe, Matthew E., Zimmer, Jennifer S., Metz, Thomas O., Adkins, Joshua N., Smith, Richard D., and Heffron, Fred. Sun . "Targeted Protein Degradation by Salmonella under Phagosome-Mimicking Culture Conditions Investigated Using Comparative Peptidomics". United States. doi:10.1074/mcp.M600282-MCP200.
@article{osti_912500,
title = {Targeted Protein Degradation by Salmonella under Phagosome-Mimicking Culture Conditions Investigated Using Comparative Peptidomics},
author = {Manes, Nathan P. and Gustin, Jean K. and Rue, Joanne and Mottaz, Heather M. and Purvine, Samuel O. and Norbeck, Angela D. and Monroe, Matthew E. and Zimmer, Jennifer S. and Metz, Thomas O. and Adkins, Joshua N. and Smith, Richard D. and Heffron, Fred},
abstractNote = {The pathogen Salmonella enterica is known to cause both food poisoning and typhoid fever. Due to the emergence of antibiotic-resistant isolates and the threat of bioterrorism (e.g., contamination of the food supply), there is a growing need to study this bacterium. In this investigation, comparative peptidomics was used to study Salmonella enterica serovar Typhimurium cultured in either a rich medium or in an acidic, low magnesium, and minimal nutrient medium designed to roughly mimic the macrophage phagosomal compartment (within which Salmonella are known to survive). Native peptides from cleared cell lysates were enriched by using isopropanol extraction and analyzed by using both LC-MS/MS and LC-FTICR-MS. We identified 5,163 distinct peptides originating from 682 proteins and the data clearly indicated that compared to cells cultured in the rich medium, Salmonella cultured in the phagosome-mimicking medium had dramatically higher abundances of a wide variety of protein degradation products, especially from ribosomal proteins. Salmonella from the same cultures were also analyzed by using bottom-up proteomics, and when the peptidomic and proteomic data were analyzed together, two clusters of proteins targeted for proteolysis were tentatively identified. Possible roles of targeted proteolysis by phagocytosed Salmonella are discussed.},
doi = {10.1074/mcp.M600282-MCP200},
journal = {Molecular & Cellular Proteomics. MCP, 6(4):717-727},
number = 4,
volume = 6,
place = {United States},
year = {Sun Apr 01 00:00:00 EDT 2007},
month = {Sun Apr 01 00:00:00 EDT 2007}
}
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