Amino Acids

Amino acids are used in every cell of your body to build the proteins you need to survive. Amino Acids have a two-carbon bond: – One of the carbons is part of a group called the carboxyl group. – The other carbon is connected to the amino group.

Carboxyl Group Made up of one carbon and 2 oxygen atoms. Has a negative charge because it has lost a hydrogen atom.

Amino Group The other carbon is connected to an NH 2 group. This has a positive charge.

Side Group (R-groups) The side groups are what makes each amino acid different from the others. 2 main groups of R-groups: polar and nonpolar Polar amino acids adjust themselves in a certain direction Called hydrophilic – they point themselves toward water Nonpolar amino acids go in any direction Called hydrophobic – point away from water

Amino Acids There are over 50 amino acids – but only 20 are used in your body. Of those 20, 9 are defined as essential The other 11 can be synthesized by your body. When amino acids bond together in long chains, it is called a Protein

Essential Amino Acids Histidine Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine

Nonessential (dispensable) Amino Acids Alanine Asparagine Aspartic Acid Glutamic Acid Serine

Conditional Amino Acids Arginine (essential in children, not adults Cysteine Glutamine Glycine Proline Tyrosine

Amino Acids building Proteins 4 step process – Primary structure – begins as a straight chain of amino acids. – Bond with disulfide bridges (chains bonded with 2 sulfur atoms

Secondary structure – the original chain begins to twist (like taking a string and twisting one end) Twists like a corkscrew (alpha helix) or folds like a sheet (beta sheet) Shape is affected by hydrophobic or hydrophilic

Step three is Tertiary Structure Secondary structure begins to fold more and bonds using more disulfide bridges

Step 4 – Quaternary structure Several amino acid chains from the tertiary structures fold together in a blob – They wind and entwine with each other