A Bottom-Up Proteomics Study of Cancer Contributor, H. pylori


My name is Theresa Gozzo.  I’m a chemistry major and biochemistry minor, and I’ll be conducting honors research under Professor Poutsma and Professor Forsyth this summer.  I want to thank everyone again who helped support my project! I am so excited to get started!

My honors thesis is a study of a transcription factor protein of the bacterium, H. pylori.  This bacterium resides in the gastric systems of about half the world’s population and its presence leads to an increased risk of developing gastric cancers and peptic ulcers.  It secretes adhesin proteins that allow it to stick to gastric epithelial cells, but it is incredibly hard to eliminate partly because it can respond to stressful conditions, like low pH, by repressing the expression of these proteins.  It then can migrate and reattach elsewhere.  My research will target a specific transcription factor, ArsR, that represses the transcription of the adhesin, sabA.  I’m using HPLC and a linear trap quadrupole mass spectrometer to help better understand how the signaling works.  I will be investigating the post-translation modification that activates ArsR to block gene transcription.  If we can learn more about this process, information can eventually be applied to treat H. pylori infection.

So far, great progress has been made, with help from other dedicated students, to get the ionization source (nanospray) for the mass spectrometer running optimally.  I will soon be prepping the pure transcription factor for preliminary investigation.  I can’t wait to begin!


  1. tagozzo says:

    I’m sorry it took so long to get back to you, Mr. Speer. As I’m only an undergraduate I cannot speak for the majority of scientists working in analytical chemistry, but the techniques I am learning lend themselves to all sorts of inter-departmental studies. The major tools for proteomic analysis lie in mass spectrometry, for example. I will certainly be looking at masses of post-translational modifications, specifically phosphorylation. I will be using electron transfer dissociation to break apart my peptide fragments. This method will cause fragmentation of my peptides without knocking off the phosphate groups, if present. Then, using the mass spectra and database searching, I will be able to identify whether my target protein is being phosphorylated. Thank you for your questions and well wishes, friend!

  2. That sounds terrific! This a significantly interesting combination of biochemistry and analytical chemistry techniques, and it sounds like the content you will be producing is very useful to real-life application by other biochemists. s a question, do a lot of other analytical chemists perform this cross-subject analysis? In addition, how does mass isolation relate to post-translational modification? Are you looking at the mass fragments of these modifications? I hope all goes well!