Peptide: Difference between revisions

This is the '''<scene name='Peptide/Emartz_view1/8'>backbone</scene>''' of 1 amino acid.  Adding to the backbone with an additional amino acid on each side gives a '''<scene name='Peptide/Emartz_view2/7'>tripeptide</scene>''' (3 amino acids).  No side groups are shown, and most hydrogens are omitted.  Now each amino acid has a 1 carbon side group so we have '''<scene name='Peptide/Emartz_view3/5'>Ala-Ala-Ala</scene>''' (tri-alanine).  Adding a carbon chain plus an NH3 on the first amino acid gives '''<scene name='Peptide/Emartz_view4/6'>Lys-Ala-Ala</scene>'''.  Adding '''<scene name='Peptide/Emartz_view5/5'> three more carbons </scene>''' to the 3rd amino acid gives isoleucine: Lys-Ala-Ile.  The 4th amino acid is threonine with its hydroxyl, giving '''<scene name='Peptide/Emartz_view6/2'> Lys-Ala-Ile-Thr</scene>'''.  Here is the shape of the '''<scene name='Peptide/Emartz_view7/2'>tetrapeptide</scene>''' (4 AAs).  The stick representation has too much detail for larger proteins, so the α-carbons are connected with a line called the '''<scene name='Peptide/Emartz_view8/4'>backbone trace</scene>'''.  Showing only the '''<scene name='Peptide/Emartz_view9/6'>backbone</scene>''' makes it easier to see the path of the protein chain (its secondary and tertiary structure).