Abstract
For the comparative analysis of post-translationally modified proteins, two samples are digested proteolytically and the resulting peptides from each are then converted to d₀- and d₃-methyl esters, respectively.  The two samples are then mixed together and analyzed by nano flow HPLC interfaced to electrospray ionization on a tandem linear ion trap-Fourier transform mass spectrometer (LTQ-FTMS).  This instrument operates at a resolution of 100,000, measures masses to three decimal places, and records the molecular masses of peptides in each sample at the high attomole level.  For the analysis of phosphorylated proteins, immobilized metal affinity chromatography (IMAC) is employed to enrich the sample for phosphopeptides prior to analysis by nanoflow HPLC.  Phosphorylation levels in the two samples are deduced from the ratios of ion abundances observed for d₀- and d₃- labeled peptides in each sample.  Sequence information on these peptides is obtained by inducing fragmentation at peptide amide bonds by either collision activated dissociation (CAD) or by electron transfer dissociation (ETD).  The latter technique is ideally suited for the analysis of phosphopeptides.

The above approaches will be illustrated with examples from our research to characterize (a) post translational modifications on Histones that control gene expression, gene silencing, DNA damage repair, recombination, etc,  (b) phosphorylation sites on proteins involved in cell migration, and (c) phosphopeptides presented to the immune system on cancer cells that might be used as potential cancer vaccines or therapeutics.  Experiments that use a combination of CAD, charge neutralization, and ETD to fragment and characterize posttranslational modifications on intact proteins will also be discussed.

Background
Dr. Donald F. Hunt, University Professor of Chemistry and Pathology at the University of Virginia, pioneered the development of methodology for protein and peptide sequence analysis based on tandem mass spectrometry.  This is now the most sensitive method in the world and is used heavily in the emerging field of proteomics.  Dr. Hunt joined the faculty at the University of Virginia as an assistant professor in September, 1968 and was promoted to associate professor and full professor in 1973 and 1978, respectively.  Prior to assuming these positions, he spent a year at the Massachusetts Institute of Technology as a National Institute of Health Postdoctoral Trainee in Mass Spectrometry under the guidance of Professor Klaus Biemann.  The principal investigator obtained both his B.S. and Ph.D. (1967) degrees from the University of Massachusetts.  Research for the doctoral dissertation was carried out under the direction of Professors Marvin Rausch and Peter Lillya in the area of organotransition metal chemistry.  Dr. Hunt is a co-inventor on more than 10 patents and patent applications and has over 250 scholarly publications to his credit.

In 1990, he received the Charles H. Stone Award sponsored by the Piedmont Section of the American Chemical Society.  In 1992 he was named Virginia's Outstanding Scientist and also shared the Pehr Edman Award with Professor Klaus Biemann for outstanding achievements in the application of mass spectrometry to the contemporary microsequence analysis of proteins.  The Distinguished Contribution Award from the American Society for Mass Spectrometry was presented to Dr. Hunt in 1994 for his development of electron capture negative ion mass spectrometry.  In 1996, he was the first recipient of the Christian B. Anfinsen Award from the Protein Society for development of new technology in the field of protein chemistry.  He received the Chemical Instrumentation Award sponsored by the American Chemical Society in 1997.  This award recognizes Professor Hunt for development of instrumentation capable of sequencing peptides and proteins at the attomole level.  In 2000, Professor Hunt was the recipient of both the Frank F. Field and Joe L. Franklin award presented by the American Chemical Society for outstanding achievement in the field of mass spectrometry and the Thomson Medal from the International Mass Spectrometry Society.  Professor Hunt is a consultant to ThermoFinnigan and MDS-Protana, Inc.

Meeting details

Date:	Tuesday	January 18, 2005
Time:	6:00 pm	Social hour, registration (no-host cocktails)
	7:00 pm	Dinner
	8:00 pm	Lecture
Dinner:	Buffet featuring:	Pork Loin Roast with Peppercorn Sauce
		Breast of Chicken, Florentine
		Stuffed Prawns with Lobster Sauce
		Vegetarian Lasagna
Cost:	$30.00	BAMS members.
	$40.00	Non-members.
	$60.00	BAMS membership plus dinner cost
	$15.00	Students only.
		Dinner reservations required by noon on Friday January 14, 2005

Note: 2005 dues need to be paid to obtain member price.  Dues ($30) may be paid when registering for dinner.

Maps & directions
Michaels at Shoreline
2960 Shoreline Blvd.
Mountain View, CA 94043
(650) 962-1014
Mapquest map link

Did you see or hear about the BAMS talk by Professor Murayama entitled "What is Mass?"  What is it we are measuring after all?  Check it out!  Go to ctp.berkeley.edu and click on "Popular Talks & Articles" for a QuickTime file.

As a service to our members, we post Employment postings.

As a trial service to our members, we are now posting Situations Wanted.  (Note: BAMS isn't a career center and will only post brief positions wanted for BAMS members only).

The San Francisco Bay Area Mass Spectrometry discussion group was formed in 1980 to provide a regular gathering for people interested in mass spectrometry and allied topics. BAMS currently has a membership of about 280 individual and 20 corporate members, and meets 8-10 times per year for a midweek dinner and lecture.  Meetings attract between 30 and 90 people, and are held at a restaurant or hotel in the bay area convenient for our speaker.  We usually convene at 6:00 pm for cocktails, dinner at 7:00 pm, and lecture at 8:15 pm.

If you have suggestions for a meeting topic, or know of a prominent mass spectrometrist who will be visiting the bay area, please contact our program chair.

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BAMS has been fortunate to have had many excellent speakers in our short history.
If you have suggestions for a meeting topic please contact our program chair.
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If you have comments or suggestions for this web site, please email me at hugh-gregg@llnl.gov

Last update: 1/4/2005