Center for Molecular and Medical Sciences Mass Spectrometry

The UCLA Center for Molecular and Medical Sciences Mass Spectrometry is located on the ground floor of the recently completed Molecular Sciences Building on the UCLA campus. The Center is jointly supported by the Departments of Chemistry & Biochemistry (College of Letters and Sciences) and Psychiatry & Biobehavioral Sciences and The Neuropsychiatric Institute (School of Medicine). The Center is a research and service facility available to all members of the UCLA campus and elsewhere. The available equipment has the capability of analysing a diverse array of organic and inorganic molecules including compounds of biological origin such as peptides and proteins, carbohydrates, and oligonucleotides. One high resolution magnetic sector instrument is reserved for solid probe GC analyses via EI and CI for accurate mass determination. Two other high resolution magnetic sector instruments are reserved for analyses by Fast Atom Bombardment; one of these instruments is fitted with a zenon gun and the other is fitted with a caesium ion gun. The facility has one triple quadrupole instrument is reserved for electrospray ionization; this instrument has a dedicated HPLC. The Center also has one laser desorption-time of flight mass spectrometer which is used for peptide, protein and oligonucleotide analyeses. Two quadrupole GC/MS instruments are also available, one for EI only and the other fitted with EI and CI capability and with positive and negative ion detection.

Research. Because of the capabilities that contempory mass spectrometry offers for the structural characterization of compounds of biological importance, the number of research projects in which the lab is involved in continually increasing. Below are listed 8 of the current ongoing projects. This list is not complete.

1. Biochemical studies of lipid binding proteins. Lipid binding and transport proteins are essential in the maintenance of cellular and bodily function. Detailed biophysical investigations of these proteins are necessary to understand their structure, specificity and modes of action. Two active projects are ongoing. One is focussed on Cerebroside Sulfate Activator protein This investigates the chemical/physical properties of cerebroside sulfate activator which is a small, stable, water soluble protein, virtually ubiquitious in mammalian tissues and thought to be essential for the turnover of membrane lipid components, most notably myelin membrane lipids. The other project investigates the biochemical/biophysical properties of members of the lipocalin and lipohilin proteins that are found in tears.

2. Characterization of membrane bound proteins. These proteins include neurotransmitter and hormone receptors, and proteins involved in vesicle docking etc. Investigations are ongoing into the characterization of cystine string proteins from Torpedo electric organ and mammalian brain. The recent results have been very promising and the intention is to expand this project to include members of the G-protein coupled receptors including opioid receptors..

3. Surface protein anchoring in gram-positive bacteria. The mass spec lab has a crucial role in the on-going investigation directed by Dr. Olaf Schneewind, M.D., Ph.D. (Dept. Microbiology and Immunology) which investigates the structure of the protein-carbohydrate link in the cell walls of gram negative bacteria.

4. Iron aquisition by Histoplasma capsulatum, an AIDS opportunist. This on-going project investigates the structure of the iron chelating siderophores produced by H. capsulatum. The mass spec lab has a crucial role in purifying and characterizing the siderophores produced by this fungus.

5. Mechanisms of apoptotic cell death. Work done in the mass spec lab help characterise the antigen that is responsible for initiating the apoptotic process in cultured neurons as a neutral glycosphingolipid. This work involves further characterization of members of this compound class, the processes involved in their formation, and the sequence of biochemical events involved in the initiation of apoptosis.

6. Mechanisms of lipid oxidation in atherosclerosis. The mass spec lab has become a crucial component in the research conducted by the Atherosclerosis Research Unit which involves characterization of the bioactive products formed during phospholipid oxidation.

7. Role of beta-carbolines in Parkinson's Disease. In collaboration with Dr. Michael Collins (Lyolya University Medical School, Chicago) the role of beta-carbolines in PD is being investigated because of the structural and neurochemical toxicity similarities these compounds have with the known neurotoxin MPTP.

8. Functional roles of Ubiquinone in yeast and human cells. This project involves a continuing investigation of the structure of the intermediates involved in ubiquinone biosynthesis and the regulation of the biosynthetic pathway.

Facilities. The Center consists of approximately 2300 square feet of floor space fitted with benches for wet chemistry, one 6 foot fume cupboard, two sinks, and plumbed with all the necessary gases and vaccuum lines. Two offices, each of about 144 square feet, are attached to the main lab.

Specialized Equipment

• A Sciex API IIIR triple quadrupole electrospray mass spectrometer with a dedicated Applied Biosystems 140B HPLC and operated via a Quadra 9000 Macintosh computer.
• Two VG ZAB-SE reverse geometry, extended mass range, magnetic sector mass spectrometers both equipped with FAB and EI/CI sources and each controlled via a PDP 11/250 computers.
• A VG Autospec computer controlled magnetic sector mass spectrometer used primarily for EI and CI determinations of elemental composition at high mass resolution.
• A PerSeptive Biosystems Voyager RP laser desorption-time-of-flight mass spectrometer.
• An HP 5985B quadrupole gas chromatograph/mass spectrometer with EI, CI, negative and positive ion capability.
• An HP 5970 Mass Selective Detector (bench top GC/MS instrument, EI mode only)
• Two HP 1090 Chemstation computer controlled HPLC (binary and tenary system) with a diode array detector, a two channel A/D converter for recording signals from up to two additional detectors, and an automatic sample injector.

Staff

Kym F. Faull, Ph.D., Associate Professor in Residence, Department of Psychiatry & Biobehavioral Sciences, Director of the Mass Spec lab.

Kenneth Conklin, B.S., Senior Research Engineer, Department of Psychiatry & Biobehavioral Sciences.

Richard L. Stevens, Ph.D., Senior Research Engineer, Department of Psychiatry & Biobehavioral Sciences.

Wayne Poon, B.S., assigned Teaching Assistant, Ph.D. student, Department of Chemistry & Biochemistry.