## Abstract The 8‐old parallel α/β‐barrel topology is encountered in proteins that display an impressive variety of functions, suggesting that this topology may be a rather nonspecific and stable folding motif. Consequently, this motif can be considered as an interesting framework to design novel p
Structural principles of α/β barrel proteins: The packing of the interior of the sheet
✍ Scribed by Arthur M. Lesk; Carl-Ivar Brändén; Cyrus Chothia
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- English
- Weight
- 850 KB
- Volume
- 5
- Category
- Article
- ISSN
- 0887-3585
No coin nor oath required. For personal study only.
✦ Synopsis
Alpha/beta barrel structures very similar to that first observed in triose phosphate isomerase are now known to occur in 14 enzymes. To understand the origin of this fold, we analyzed in three of these proteins the geometry of the eight-stranded beta-sheets and the packing of the residues at the center of the barrel. The packing in this region is seen in its simplest form in glycolate oxidase. It consists of 12 residues arranged in three layers. Each layer contains four side chains. The packing of RubisCO and TIM can be understood in terms of distortions of this simple pattern, caused by residues with small side chains at some of the positions inside the barrel. Two classes of packing are found. In one class, to which RubisCO and TIM belong, the central layer is formed by a residue from the first, third, fifth, and seventh strands; the upper and lower layers are formed by residues from the second, fourth, sixth, and eighth strands. In the second class, to which GAO belongs, this is reversed: it is side chains from the even-numbered strands that form the central layer, and side chains from the odd-numbered strands that form the outer layers. Our results suggest that not all proteins with this fold are related by evolution, but that they represent a common favorable solution to the structural problems involved in the creation of a closed beta barrel.
📜 SIMILAR VOLUMES
Proteins containing two closely packed /3-sheets comprise an important class of biopolymers. Rotational and dipole strengths have been determined by the exciton coupling model for interacting pairs of two idealized flat /%sheets and for the double /3-sheets of seven globular proteins: plastocyanin,
## Abstract The preferred structural pattern of antiparallel β‐barrels in proteins, described as the right‐handed tilting of the peptide strands with respect to the axis of the barrel, is accounted for in terms of intra‐ and interchain interaction energies. It is related to the preference of β‐shee
## Abstract The (β/α)~8~‐barrel is one of the most abundant folds found in enzymes. To identify the independent folding units and the segment(s) that correspond to a minimum core structure within a (β/α)~8~‐barrel protein, fragmentation experiments were performed with __Escherichia coli__ phosphori