Alpha sheet
Автор:
Jesse Russell,Ronald Cohn, 120 стр., издатель:
"Книга по Требованию", ISBN:
978-5-5140-7216-3
High Quality Content by WIKIPEDIA articles! The alpha sheet (also known as an alpha pleated sheet or a polar pleated sheet) is a hypothetical secondary structure in proteins, first proposed by Linus Pauling and Robert Corey in 1951. The hydrogen bonding pattern in an alpha sheet is similar to that of a beta sheet, but the orientation of the carbonyl and amino groups in the peptide bond units is distinctive; in a single alpha strand, all of the carbonyl groups are oriented in the same direction on one side of the pleat, and all of the amino groups are oriented in the same direction on the opposite side of the sheet. Thus the alpha sheet accumulates an inherent separation of electrostatic charge, with one edge of the sheet exposing negatively charged carbonyl groups and the opposite edge exposing positively charged amino groups. Unlike the alpha helix and beta sheet, the alpha sheet configuration does not require all component amino acid residues to lie within a single region of...