Amino Acids (AA)

There are 20 AA.  They are in alphabetical order:

Alanine.  Arginine*.  Asparagine.  Aspartic Acid.  Cysteine.
Glutamic Acid.  Glutamine.  Glycine.  Histidine*.  Isoleucine*.
Leucine*.  Lysine*.  Methionine*.  Phenylalanine*.  Proline.
Serine.  Threonine*.  Tryptophan*.  Tyrosine.  Valine*.

The atoms in AA are:  hydrogen, carbon, nitrogen, oxygen,
and sulfur.

We need to understand AA structure and properties to be able
to understand protein structure and properties.  Even a small
relatively simple protein is made out and depend on the AA which
comprises it.

Humans can produce 10 of the 20 AA.  The others must be
present in our diet.  Failure to obtain enough of even 1 of the
10 essential AA (those we cannot make) will mean that the body
will break its own tissues to obtain that one AA!

Unlike fat and starch, humans do not store excess AA for
later use;  AA must be part of our daily diet.  [Compare with
glucose which is stored in the liver and muscles (in the form of
glycogen).  It would be handy if the same applied to AA!].

The essential AA are indicated by an * in the above list.
These AA must be in your diet.

Plants, of course, must be able to produce all the AA.
Humans though lacks the enzymes needed to synthesize all 20 AA.

Sources

1) Arizona State University
Center for Bioenergy & Photosynthesis
DNA, RNA and Protein Synthesis
http://photoscience.la.asu.edu/photosyn/courses/bio_343/lecture/DNA-RNA.html

2) University of Arizona
Department of Biochemistry and Molecular Biophysics
The Biology Project
The Chemistry of Amino Acids
September 30, 2003
www.biology.arizona.edu/biochemistry/problem_sets/aa/aa.html

3) University of Texas Medical Branch
Cell Biology Graduate Program
What happens at the site of the ribosome?
http://cellbio.utmb.edu/CELLBIO/ribosome.htm

4) Biology
John W. Kimball
Tufts University
Addison-Wesley Publishing Company
April 1975

Site Search Tags:
none