Search
- https://bio.libretexts.org/Courses/Ouachita_Baptist_University/Reyna_Cell_Biology/02%3A_2-(T2-first_lecture)_Protein_Structure/2.03%3A_Understanding_Protein_Conformation/2.3.01%3A_C1._Main_Chain_ConformationsIn contrast to micelles and bilayers, which are aggregates of single and double chain amphiphiles, proteins are covalent polymers of 20 different amino acids, which fold, to a first approximation, in ...In contrast to micelles and bilayers, which are aggregates of single and double chain amphiphiles, proteins are covalent polymers of 20 different amino acids, which fold, to a first approximation, in a thermodynamically spontaneous process into a single unique conformation, theoretically at a global energy minimum. This chapter section will investigate the possible conformations available to proteins, just as we studied the conformations of free fatty acids and acyl chains in lipid aggregates.
- https://bio.libretexts.org/Workbench/Biochem_Remix_Acevedo/04%3A_The_Three-Dimensional_Structure_of_Proteins/4.01%3A_Secondary_Structure_and_LoopsA beta sheet would then consist of multiple strands, since each "strand" is separated from other "strands" by an intervening contiguous stretch of amino acid which bends within the protein in a way th...A beta sheet would then consist of multiple strands, since each "strand" is separated from other "strands" by an intervening contiguous stretch of amino acid which bends within the protein in a way that allows the next section of the peptide backbone, the next "strand", to H-bond with the first "strand". But remember, even in this case, all the H-bonds holding the alpha and beta structures together are intramolecular.
- https://bio.libretexts.org/Bookshelves/Biochemistry/Fundamentals_of_Biochemistry_(Jakubowski_and_Flatt)/01%3A_Unit_I-_Structure_and_Catalysis/04%3A_The_Three-Dimensional_Structure_of_Proteins/4.02%3A_Secondary_Structure_and_LoopsThe page provides a detailed exploration of secondary structures in proteins, focusing on alpha helices, beta sheets (parallel and antiparallel), 310 helices, pi helices, and loops and turns. It expla...The page provides a detailed exploration of secondary structures in proteins, focusing on alpha helices, beta sheets (parallel and antiparallel), 310 helices, pi helices, and loops and turns. It explains the roles of hydrogen bonds in stabilizing structures and discusses sequence determinants that influence structural propensities. The text also covers the characteristics and roles of loops, turns, and linkers, and examines amino acid propensities for forming different secondary structures.
- https://bio.libretexts.org/Courses/Chemeketa_Community_College/Cell_Biology_for_Allied_Health/08%3A_Biological_Molecules/8.03%3A_ProteinsWhereas nucleotides all are water soluble and have the same basic composition (sugar, base, phosphate) and the sugars also are water soluble and mostly contain 5 or 6 carbons (a few exceptions), the a...Whereas nucleotides all are water soluble and have the same basic composition (sugar, base, phosphate) and the sugars also are water soluble and mostly contain 5 or 6 carbons (a few exceptions), the amino acids (general structure below) are structurally and chemically diverse.
- https://bio.libretexts.org/Bookshelves/Biochemistry/Book%3A_Biochemistry_Free_and_Easy_(Ahern_and_Rajagopal)/03%3A_Structure__Function/3.03%3A_ProteinsWhereas nucleotides all are water soluble and have the same basic composition (sugar, base, phosphate) and the sugars also are water soluble and mostly contain 5 or 6 carbons (a few exceptions), the a...Whereas nucleotides all are water soluble and have the same basic composition (sugar, base, phosphate) and the sugars also are water soluble and mostly contain 5 or 6 carbons (a few exceptions), the amino acids (general structure below) are structurally and chemically diverse.
- https://bio.libretexts.org/Courses/Roosevelt_University/BCHM_355_455_Biochemistry_(Roosevelt_University)/04%3A_Proteins-_Structure_and_Folding/4.07%3A_The_Three-Dimensional_Structure_of_Proteins/4.7.01%3A_Main_Chain_ConformationsThe atoms in the main chain of the peptide, N, C α , C (the carbonyl C), and the carbonyl O, are arranged in the familiar zig-zag fashion, characteristic of the lowest energy conformer. This can be ac...The atoms in the main chain of the peptide, N, C α , C (the carbonyl C), and the carbonyl O, are arranged in the familiar zig-zag fashion, characteristic of the lowest energy conformer. This can be accounted for by delocalizing the nonbonding electron pair of the N to the carbonyl C, forming a double bond, with the pi-bonded electrons of the carbonyl C-O bond moving to the O.
- https://bio.libretexts.org/Courses/Roosevelt_University/BCHM_355_455_Biochemistry_(Roosevelt_University)/04%3A_Proteins-_Structure_and_Folding/4.07%3A_The_Three-Dimensional_Structure_of_Proteins/4.7.02%3A_Secondary_Structure_and_LoopsShifting back to the Greek letter naming system, the gamma turn, the second most common turn, has just three total residues (i th , i th +1, and i th +2) with the hydrogen bond between the backbone ca...Shifting back to the Greek letter naming system, the gamma turn, the second most common turn, has just three total residues (i th , i th +1, and i th +2) with the hydrogen bond between the backbone carbonyl of the i th amino acid and the backbone amide H of the i th +2 amino acid.
