Peptide: Difference between revisions
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==Peptides & Backbones== | ==Peptides & Backbones== | ||
This is the '''<scene name='Peptide/Emartz_view1/6'>backbone</scene>''' of 1 amino acid. Adding to the backbone with an additional amino acid on each side gives a '''<scene name='Peptide/Emartz_view2/6'>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_view3/4'>Ala-Ala-Ala</scene>''' (tri-alanine). Adding a carbon chain plus an NH3 on the first amino acid gives '''<scene name='Peptide/Emartz_view4/5'>Lys-Ala-Ala</scene>'''. Adding '''<scene name='Peptide/Emartz_view5/4'> | This is the '''<scene name='Peptide/Emartz_view1/6'>backbone</scene>''' of 1 amino acid. Adding to the backbone with an additional amino acid on each side gives a '''<scene name='Peptide/Emartz_view2/6'>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_view3/4'>Ala-Ala-Ala</scene>''' (tri-alanine). Adding a carbon chain plus an NH3 on the first amino acid gives '''<scene name='Peptide/Emartz_view4/5'>Lys-Ala-Ala</scene>'''. Adding '''<scene name='Peptide/Emartz_view5/4'> three more carbons </scene>''' to the 3rd amino acid gives '''<scene name='Peptide/Emartz_view6/2'>''' isoleucine</scene>: 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_view8/3'>backbone trace</scene>. Showing only the <scene name='Peptide/Emartz_view9/5'>backbone</scene> makes it easier to see the path of the protein chain (its secondary and tertiary structure). | ||
Revision as of 08:31, 22 February 2008
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Peptides are chains of amino acids linked by peptide bonds. Long peptides, or polypeptides, are called proteins.
Peptides & BackbonesPeptides & Backbones
This is the of 1 amino acid. Adding to the backbone with an additional amino acid on each side gives a (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 (tri-alanine). Adding a carbon chain plus an NH3 on the first amino acid gives . Adding to the 3rd amino acid gives : Lys-Ala-Ile. The 4th amino acid is threonine with its hydroxyl, giving . Here is the shape of the (4 AAs). The stick representation has too much detail for larger proteins, so the α-carbons are connected with a line called the . Showing only the makes it easier to see the path of the protein chain (its secondary and tertiary structure).