Daily Newsletter February 16, 2012

Daily Newsletter February 16, 2012

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Today's Topic: Amino Acid Biosynthesis (Aromatics and Special Cases)

Yesterday we covered the basics of amino acid biosynthesis, but what about those amino acids that in humans are considered ESSENTIAL? 

Aromatic Amino Acids contain an aromatic ring structure.  The pathway below shows the pathway to build CORISMATE (corismic acid), which is the precursor to all aromatic amino acids (can you name them?). 

  

The next pathway shows the biosynthesis of tryptophan:

 

Below are the pathways for Valine, Leucine and Isoleucine biosynthesis.  The numbers are references to enzymes.  At present, you do not need to learn these.

Review these pathways.  Look them over, and research them if needed.  Your goal right now is to learn how to articulate these pathways.  What is happening?  What are the precursors that we are using?  Remember, central metabolism got its name for a reason.

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Daily Challenge:
Clearly articulate the biosynthesis of tryptophan. Consider, what does it take to make an aromatic amino acid? Why would most animals have lost this capability?