Selvaraj S, Gromiha M M
Department of Physics, Bharathidasan University, Tamil Nadu, India.
J Protein Chem. 1998 Jul;17(5):407-15. doi: 10.1023/a:1022514400583.
The (alpha/beta)8 barrel proteins, in spite of having a common fold, do not show any sequence similarity. In order to understand the factors which are responsible for maintaining the common fold, the three-dimensional structures of 36 (alpha/beta)8 barrel proteins are analyzed for the presence of identical amino acid clusters or physicochemically similar clusters. The results reveal 14 identical amino acid clusters and a large number of physicochemically similar clusters. Further analysis of the similar clusters points to the conservation of secondary structures, the presence of pairs of residues occupying topologically equivalent secondary structures, and the presence of certain key residues which may play a vital role in directing and stabilizing the (alpha/beta)8 barrel fold.
（α/β）8桶状蛋白尽管具有共同的折叠结构，但在序列上没有任何相似性。为了了解维持这种共同折叠结构的因素，对36种（α/β）8桶状蛋白的三维结构进行分析，以寻找相同氨基酸簇或物理化学性质相似的簇。结果揭示了14个相同氨基酸簇和大量物理化学性质相似的簇。对相似簇的进一步分析表明，二级结构具有保守性，存在占据拓扑等价二级结构的残基对，以及某些关键残基，这些残基可能在引导和稳定（α/β）8桶状折叠结构中起着至关重要的作用。
