Alpha helices and beta sheets are each held together by gravity

For example fibroin, one of the main components of spider silk and one of the strongest proteins known, consists mainly of beta sheets while keratin another very stable structural protein (the stuff hair and fingernails are made of) consists of four alpha helices alternating with three beta turns is believed to get most of its strength from ...

Alpha helices and beta pleated sheets are two types of secondary structure found in proteins. The names refer to the shapes the amino acid chain takes on. They are both held together by hydrogen bonding. An alpha helix is a right-handed helix that is held together by hydrogen bonding. I have answered this question previously, as part of a more general question: Why are secondary structures other than alpha helices and beta strands so rare? Here is a part of my answer: > To answer your question in one word: stability 1) Helices...

Sort the following phrases as descriptions of alpha helices, beta turns or all alpha Helices Beta Sheets Beta Turns 1st residue hydrogen- bonded to 5^th residue (that is, residue n is H- bonded to residue n + 4) all - NH groups point in the same direction successive R groups point in opposite directions 1^st residue (that is, residue n is H- bonded to residue n+3 contains-NH hydrogen bonded to ... Sep 29, 2013 · The alpha helix is, specifically, a right handed helix held together by hydrogen bonds (H-bonds) between the carbonyl oxygen and amide hydrogen of the polypeptide backbone. Jan 27, 2014 · Sort the following phrases as descriptions of alpha helices, beta sheets, beta turns, or all -) 1st residue hydrogen bonded to 5th residue (that is, residue n is H-bonded to residue n+4) -) contains -NH hydrogen-bonded to C=O -) all -NH groups point in the same direction -) 1st residue hydrogen bonded to 4th residue (that is, residue n is H-bonded to residue n+3) -) successive R groups point ... Oct 09, 2011 · Alpha helices and beta sheets are both held together by hydrogen bonds. The difference between the two is their structure. The hydrogen bonds are held together allowing the protein to be folded differently. The alpha helices looks like a spiral and the beta sheet looks like sheet but with a zig zaggy look. C. Both alpha-helices and beta-sheets form only from adjacent (sequential) amino acid residues in the polypeptide. D. A and B E. B and C Which of the following amino acid residues form hydrogen bonds with Ala residues located in an alpha - helix? A. Residues in a neighbouring alpha-helix. B. Residues located within the same alpha-helix. C. The protein chains are held together by intermolecular hydrogen bonding, that is hydrogen bonding between amide groups of two separate chains. This intermolecular hydrogen bonding in the beta-pleated sheet is in contrast to the intramolecular hydrogen bonding in the alpha-helix.

Motifs of Protein Structure. Protein molecules are organized in a structural hierarchy Formation of secondary structures ! Alpha helices Beta Sheets Characterized by- main chain NH and CO groups participating in H-bonds to each other. superimposed on secondary structure. alpha-helices and/or sheets beta-sheets are folded up to form a compact globular molecule held together by intramolecular bonds. Quaternary structure Two or more polypeptide chains, each with its own tertiary structure, combine to form a functional protein. Alpha-Helices Alpha-helices are formed by hydrogen bonding amino acids via their carbonly carbons and amide protons. In a helix each peptide carbonyl groups is hydrogen bonded to the amide proton four residues up the chain. Such an association of amino acids gives rise to a structure that resembles a cork screw. 7. Beta strands are other protein secondary structures. When aligned in multiple units, beta strands are referred to as beta sheets. The forces holding the strand together are hydrogen bonds. 8. Both alpha helices and beta sheets were discovered by the most famous scientist ever to graduate from OSU, Dr. Linus Pauling. 9. 7. Beta strands are other protein secondary structures. When aligned in multiple units, beta strands are referred to as beta sheets. The forces holding the strand together are hydrogen bonds. 8. Both alpha helices and beta sheets were discovered by the most famous scientist ever to graduate from OSU, Dr. Linus Pauling. 9. The most common type of secondary structure in proteins is the α-helix. Linus Pauling was the first to predict the existence of α-helices. The prediction was confirmed when the first three-dimensional structure of a protein, myoglobin (by Max Perutz and John Kendrew) was determined by X-ray crystallography.