Profiling and quantitative analysis of protein expression controlled by type III secretion system of the plant pathogen pseudomonas syringae pv. tomato Dc3000

Dacheng Ren, Leila H. Choe, Erin J. Finehout, Philip Bronstein, Thomas K. Wood, Alan Collmer, Kelvin H. Lee, David Schneider, Samuel Cartinhour

Research output: Contribution to conferencePaperpeer-review


Pseudomonas syringae pv. tomato DC3000 is an economically important plant pathogen which causes bacterial speck in tomato. DC3000 uses a type III secretion system (TTSS) to deliver virulence factors into the plant cells. Previously, we have performed 2-D electrophoresis of intracellular and secreted proteins of DC3000 and its isogenic ΔhrpL mutant (hrpL encodes a sigma factor of the TTSS) grown in bioreactors. Also, we have shown that the TTSS is regulated by quorum sensing (bacterial gene regulation by sensing the cell density). In this study, we discuss the use of proteomics to facilitate the annotation of the genome using 2-D gels and shotgun proteomics. The protein spots from 2-D gels were identified using MALDI-TOF/TOF mass spectrometry to generate the 2-D maps of the intracellular and secreted proteins. In total, over 1200 open reading frames were identified from this organism. Quantitative changes in protein expression for DC3000 compared to AhrpL mutant will be discussed. In addition, the quorum sensing signal of DC3000 was identified to be 3-oxohexanoyl-homoserine lactone using mass spectrometry. Control of TTSS using quorum sensing antagonist (5Z)-4-bromo-5-(bromomethylene)-3-butyl-2(5//)- furanone will be discussed.

Original languageEnglish (US)
Number of pages1
StatePublished - 2005
Event05AIChE: 2005 AIChE Annual Meeting and Fall Showcase - Cincinnati, OH, United States
Duration: Oct 30 2005Nov 4 2005


Other05AIChE: 2005 AIChE Annual Meeting and Fall Showcase
Country/TerritoryUnited States
CityCincinnati, OH

All Science Journal Classification (ASJC) codes

  • General Engineering

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