Poster Presentation 22nd Annual Lorne Proteomics Symposium 2017

SWATH-MS proteome profiling of copper-stressed Pseudomonas aeruginosa PAO1 provides leads for functional characterization (#215)

Bradley W Wright 1 , Sheemal Kumar 1 , Christoph Krisp 2 , Karthik Kamath 2 , Mark P Molloy 1 2
  1. Chemistry and Biomolecular Sciences, Macquarie University, Sydney, NSW, Australia
  2. Australian Proteome Analysis Facility, Macquarie University, NSW, Australia

The opportunistic pathogen Pseudomonas aeruginosa is well known for its environmental and metabolic versatility, and large genome of 6.3Mbp. Many proteins are yet to be functionally characterized and the expression of some remain to be verified.  In this study, a proteome profile was produced of copper (Cu2+) stressed P. aeruginosa PAO1 membrane and whole cell proteome fractions through the data-independent analysis technique SWATH-MS, resulting in ~2000 non-redundant proteins being quantified. Of these proteins 83 were found to be differentially regulated when cultured under stress from excess copper (±1.5, p-value <0.01). Examples of new proteins shown to respond to copper stress include: PA2807, a protein predicted to have a role in copper binding; proteins PA2064 and PA2065, proteins that have strong sequence similarity to the copper-related CopA and CopB proteins of Pseudomonas syingae; PA2505, a protein previously identified for the specific uptake of tyrosine, but now hinted to be involved in the non-selective diffusion of ions across the membrane, and finally, PA3920, currently described as a probable metal P-type ATPase, but now shows evidence of being a specific active transporter of Cu2+, due to strong up-regulation observed in this study and accompanying biological/molecular function predictions. Additionally, it has been predicted that approximately 361 proteins of PAO1 have now been experimentally verified as a result of this study. This equates to 6.3% of the predicted PAO1 proteome where we now have experimental evidence for the expression of these proteins.