Date: Monday, November 10, 2008
Speaker: Professor Donald F. Hunt, Departments of Chemistry and Pathology, University of Virginia, Charlottesville, VA 22904
Topic: Innovative Mass Spectrometry Technology For The Study Of Cell Signaling
Location: Middle Atlantic Mass Spectrometry Laboratory (MAMS), Johns Hopkins University Medical School, Woods Basic Science Building, West Lecture Hall, 725 N. Wolfe St., Baltimore, MD (directions)
Meeting Time: 7:30 pm
Dinner: 5:30 pm

The talk will be preceded by dinner at Bertha’s in Fell’s Point at 5:30 PM (see details below). This year, dinner will be sponsored by ThermoFisher Scientific. Though there is no charge for the dinner, you must be a member of the Baltimore-Washington MSDG (i.e. on its mailing list or from a laboratory on its mailing list) and you must contact Darlene Sutton (dsutton5@jhmi.edu) to let her know you wish to attend.

Abstract
This lecture will focus on several different aspects cell signaling and the mass spectrometry technologies developed to study them. By using electron transfer dissociation (ETD)-tandem mass spectrometry it is now possible to analyze intact proteins on a chromatographic times scale (1 protein/2-5 sec). Proteins are converted to gas-phase, positive ions by electrospray ionization and then allowed to react with fluoranthene radical anions. Electron transfer to the multiply charged protein promotes random fragmentation of amide bonds along the protein backbone. Multiple charged fragment ions are then de-protonated in a second ion/ion reaction with the carboxylate anion of benzoic acid. The m/z values for the resulting singly, doubly, and triply charged ions are used to read a sequence of 15-60 amino acids at both the N and C termini of the protein.

This information, along with the measured mass of the intact protein, is used to identify unknown proteins, to confirm the amino acid sequence of a known protein, to detect post-translational modifications, and to determine the presence of possible splice variants.

Applications of this technology to the study of class I and class II antigen processing pathways, labile post-translational modifications (phosphorylation and O-GlcNAcylation), and complex patterns of post-translational modifications on histone proteins that regulate gene expression, stem cell differentiation, reprogramming of DNA in the egg, and changes of phenotype that do not involve altering the sequence of DNA (epigenics) will be discussed.

Dinner Arrangements
Location: Berthas www.berthas.com
Address: Fells Point,734 S. Broadway, Fells Point, Baltimore, MD.
Menu: Dinner is served family style and includes:
Appetizers: Mussels; stuffed button mushrooms
Salad: Mixed field greens, served with a creamy balsamic vinaigrette.
Entrees:

• Paella (Spanish style rice dish seasoned with saffron, including chicken, scallops, chorizo sausage, shrimp, peas, and mussels)
• Grilled vegetable ravioli, served with homemade marinara sauce, fresh spinach, and Parmesan cheese.

Dessert: Various tarts

Contact: Please call Darlene at 410-955-3022 if you are coming for dinner, or email at dsutton5@jhmi.edu