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Name: Farah
Status: student
Grade: other
Location: Outside U.S.
Country: Malaysia
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 purify it.

Hope this helps.

Stephen R. Dunn Ass't Professor of Medicine (ret.) Kimmel Cancer Center & Division of Nephrology

Hi Farah,

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 benefiting mankind.

Does that help? -Alex Vira


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