Introduction - This script shows the conversion of a β-sheet to an
α-helix caused by the mutation of a Pro to Ala. Scroll down until the
text corresponding to the view is visible. (based on W._Z. Yang ,et al.,
Protein Science. 7 1875 (1998). The pdb file was kindly provided
by Dr. H.S Yuan).
This view shows a portion of the wild type protein that contains an
α-helix (GREEN) terminated by a Pro,
followed by a two stranded β-sheet.
The first strand is YELLOWand
the second isRED. The proline is shown
in spacefill and colored cpk.
Here is the mutant protein in which Pro has been converted to Ala. Note that
the α-helix (GREEN) is now two turns longer
(YELLOW).
The first strand of β-sheet has been converted to two additional
turns of the helix from the point of the Ala mutation, while the second
strand has become disordered and is not visible in the structure.