Transcript Recombinant DNA Technology for the non

Introduction to Proteomics
• First issue of
ProteomicsJan. 1, 2001
• abcNEWS.com- April 27 —
Genes may be the stuff of life,
but they're not the whole story.
Scientists wrapping up the
mammoth task of decoding the
human genome say the next
step will be understanding the
"proteome" — the proteins that
genes help make.
Search the Database for a
‘protein match’?
•
How? Explain.
Peptide Mass Fingerprinting
• Developed 1993
•
Today- automated (including Database
Searches)  500 proteins/day analyzed
(one lab)
• Goal- annotated 2D gel map.
MS-MS
• Peptide fingerprints are sufficient ot identify
proteins only in cases where the sequence of a
protein is already in a database. MS-MS can
obtain partial sequence info. from each peptide in
the fingerprint. Within the mass spectrometer,
each peptide can then be further broken down in to
ionized fragments. The goals is to produce a
ladder of fragments each differing in length by one
aa. Because each aa has different MW, the
sequence of each peptide can be deduced.
• ExPASy Molecular Biology Server
The primary objective of KEGG is to
computerize the current knowledge
of molecular interactions; namely,
metabolic pathways, regulatory
pathways, and molecular assemblies.
Current Questions?
• Are pathways identical across species?
• Do some speciez have alternative pathways
to generic ones?
• Are certain enzymes in pathway more
important than other ones?
• Kyoto Encyclopedia of Genes and Genomes
The Future is Looking Very
Small
BIOCHEMISTRY:
Protein Arrays Step Out of
DNA's Shadow
Protein arrays
• Early progress has been slow; proteins are harder to
synthesize than DNA, and plunking them down on
solid surfaces tends to cause them to unfold and
thereby lose their activity. Now, however, those
barriers appear to be crumbling. On page 1760 of
this issue, researchers at Harvard University report
creating arrays of over 10,000 proteins on a piece of
glass just half the size of a microscope slide. They
then used their arrays to study a variety of protein
functions, work that included identifying members
of the array that bind to other free-floating proteins
and to small, druglike molecules.
• Once protein microarrays are perfected,
researchers will be able to measure the
functions of thousands upon thousands of
proteins simultaneously, and rapidly
screening them all for new drug targets. It
also will be (relatively) easy to take a
potential drug candidate and screen all the
metabolic pathways to check for unwanted
reactions. But that's the future -- and it's
barely begun.
The End