Location: Outside U.S.
Date: Winter 2012-2913
What is Protein Expression and Purification (PEP)?
Protein Expression and Purification generally refers to commercial
kits/systems that are used to "make" proteins and purify them.
I'll refer you to the New England Biolabs website.
How this works is that you look at a number of proteins that a
particular cell of interest makes (or expresses). You would like to
get more of this protein so you can study the effects and how/where it
is made (i.e. what gene is responsible for it). To do this you must
isolate it by some chromatic method (2 dimensional DIGE) and then
Hope this helps.
Stephen R. Dunn
Ass't Professor of Medicine (ret.)
Kimmel Cancer Center &
Division of Nephrology
As you may already know, proteins are a chain of amino acids, and each
amino acid is defined by specific DNA sequences.
Typically, proteins are within a complex mixture and Protein
Expression is a process of locating identifying, and "tagging" the
chain of amino acids of interest.
Protein Purification is a process of extracting and isolating the
chain of amino acids of interest from the complex mixture.
Some tissues may have a high content of an amino acid researchers are
interested in. Some tissues have a low content, but are considered
high in 'value'. Protein Expression and Purification allows
Researchers to take the next step of making multilple copies in a very
short time by way of Recombinant DNA Technology and our knowledge of
the behavior of bacteria growth. As a result, these two processes
enable Scientists and Biotechnologists to do further studies on
proteins with the goal of developing products in the interest of
Does that help?
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Update: November 2011