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Updated: Aug 15, 2026

Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
Published on: May 4, 2018
The alpha aneurism: a structural motif revealed in an insertion mutant of staphylococcal nuclease
Abstract:
The x-ray crystal structure of a mutant of staphylococcal nuclease that contains a single glycine residue inserted in the C-terminal alpha-helix has been solved to 1.67 A resolution and refined to a crystallographic R value of 0.170. This inserted glycine residue is accommodated in the alpha-helix by formation of a previously uncharacterized bulge, which we term the alpha aneurism. A conformational search of known protein structures has identified the alpha aneurism in a number of protein families, including the histocompatibility antigens and hemoglobins.
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