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Quantitative Proteomics Center
Applied Biosystems Voyager De Pro MALDI-TOF
This matrix-assisted laser desorption ionization time-of-flight mass
spectrometer with delayed extraction is used to for identification of
proteins from 2D gels using peptide mass fingerprinting (peptide mass
mapping) in reflectron (high resolution mode). In linear mode
another detector is used to determine the mass of intact proteins.
Mascot Proteomics Database Server
Mascot proteomics software (Matrix Science Ltd.) running on an HP
xw4400 with Intel Core2 Due Extreme x8600 processor, 4 Gb memory and 1
TB hard disk space. This database server allows comparison
between mass spectra and protein databases to facilitate the
identification of proteins.
Isoelectric Focusing
Two GE Healthcare IPGphor isoelectric focusing units allow separation
of proteins on the basis of charge. These units are used in the first
dimension of 2D gel electrophoresis in support of the DIGE
technique. Our three units are equipped with computer
logging of run progress for quality assurance.
SDS PAGE Electrophoresis
The GE Healthcare Ettan DALTsix SDS PAGE electrophoresis unit with
power supply and external refrigerated circulator allows separation of
proteins on the basis of size. This unit is used in the second
dimension of 2D gel electrophoresis in support of the DIGE
technique. This unit is equipped with computer logging of
run progress for quality assurance.
Typhoon Trio Laser Imager
The Typhoon Trio (GE Healthcare) is a laser scanner used for
fluorescence imaging. This system includes 3 lasers and allows
imaging of three discrete images with negligible spillover for the DIGE
workflow.
DyCyder 2D
This software package (GE Healthcare) is used for the analysis of
relative expression of proteins based on fluorescence signals. It
uses the images produced by the Typhoon imager to detect relative
differential regulation of proteins.
Ettan Spot Picker
This robotic system (GE Healthcare) picks protein spots from 2D gels
and transfers them to bar-coded 96-well plates using spot coordinates
generated by the DeCyder software.
Ettan Digester
This gel plug and liquid-handling system (GE Heathcare) performs in-gel
digestion of proteins in acrylamide plugs collected from 2D gels in
bar-coded 96-well plates.
Synapt G2 HDMS quadrupole-time-of-flight mass spectrometer (Waters Corp.)
This quadrupole acceleration,
time-of-flight mass spectrometer provides high mass accuracy for both
precursor and product masses. This innovative instrument allows
mass spectra to be recorded at alternate low (precursor) and high
(product) fragmentation voltages, and with the ProteinLynx Global
server (see below) provides improved label-free quantitation and
protein identifications. This unit is equipped with a number of
innovative features including second generation high definition mass
spectrometry (HDMS) capability for implementing ion-mobility
separations and electron-transfer dissociation (ETD) for studying
post-translational modifications.
Equipment and Software Resources
NanoAcquity UltraPerformance LC (UPLC) (Waters Corp.)
The system is designed for nano-scale, capillary, and narrow-bore
separations to attain the highest chromatographic resolution,
sensitivity, and reproducibility. Direct nano-flow offers significant
improvements over conventional nano-flow separations technologies. The
system’s 10,000 psi operating pressure capability allows for superior
high-peak capacity separations by operating longer columns packed with
sub-2 µm particles.
ProteinLynx Global Server (PLGS)
The PLGS software platform leverages the selectivity of exact mass data
and the specificity of MS^E analysis. Combined with intelligent
filtering and scoring routines, this minimizes the occurrence of false
positive results. PLGS also features Identity^E with
comprehensive peptide ion accounting informatics that mines the
label-free UPLC/MS^E data to identify more peptides/proteins with high
sequence coverage and provides quantitation for a wide variety of
samples. Enhancements to this protein identification and
quantitation software have been achieved through incorporation of
support of ion mobility spectrometry (IMS) data and the parallel
processing capability of our graphics processing unit (GPU) equipped
computer.



Elucidator Protein Expression Data Analysis System
Rosetta Elucidator system performs data management and analysis for
label-free mass spectrometry data, for accurate peptide and protein
identifications. The Elucidator system allows our center to
perform data mining and discovery of potential protein biomarkers and
proteins that are differentially expressed among different tissues,
cell types, affinity preparations genotypes, subcellular organelles,
phenotypes, drug or other treatments. Data mining matches
accurate mass and retention time measurements for mass spectrometric
features across large and complex experiments, substantially increasing
usable data from each experiment. In addition, Elucidator
provides a suite of advanced statistical analysis and visualization
tools for protein expression analysis. This software is fully
enabled to import both raw and processed data from PLGS (see above),
fully supporting our data-independent acquisition MS^E and
data-dependent acquisition workflows.

