STRUCTURAL SIMILARITY OF A DEVELOPMENTALLY-REGULATED BACTERIAL SPORE COAT PROTEIN TO BETA-GAMMA-CRYSTALLINS OF THE VERTEBRATE EYE LENS
STRUCTURAL SIMILARITY OF A DEVELOPMENTALLY-REGULATED BACTERIAL SPORE COAT PROTEIN TO BETA-GAMMA-CRYSTALLINS OF THE VERTEBRATE EYE LENS
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DOI：
10.1073/pnas.91.10.4308
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发表时间：
1994-05-10
影响因子：
11.1
通讯作者：
IKURA, M
中科院分区：
文献类型：
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作者：
BAGBY, S;HARVEY, TS;IKURA, M
来自革兰氏阴性土壤细菌黄色粘球菌的 Ca2+ 负载蛋白 S (M(r) 18,792) 的溶液结构已通过多维异核核磁共振波谱测定。蛋白 S 由四个内部同源基序组成，排列产生两个具有伪双重对称轴的结构域，整体类似于三棱柱。每个域由两个拓扑上不等价的“克里克键”组成：第二个和第四个飞蛾形成标准的希腊键，而第一和第三个飞蛾除了通常的四个β链之外，还各自包含一个规则的α螺旋。蛋白S的结构与脊椎动物眼晶状体β-γ-晶状体蛋白的结构相似，被认为与蛋白S在进化上相关。蛋白S和β-γ-晶状体蛋白都通过形成稳定的多分子组装体发挥作用。然而，S蛋白具有独特的飞蛾组织和结构域堆积，表明其寡聚模式不同，并且具有与β-γ-晶状体蛋白不同的进化途径。
The solution structure of Ca2+-loaded protein S (M(r) 18,792) from the Gram-negative soil bacterium Myxococcus xanthus has been determined by multidimensional heteronuclear NMR spectroscopy. Protein S consists of four internally homologous motifs, arranged to produce two domains with a pseudo-twofold symmetry axis, overall resembling a triangular prism. Each domain consists of two topologically inequivalent ''Creek keys'': the second and fourth moths form standard Greek keys, whereas the first and third moths each contain a regular alpha-helix in addition to the usual four beta-strands. The structure of protein S is similar to those of the vertebrate eye lens beta gamma-crystallins, which are thought to be evolutionarily related to protein S. Both protein S and the beta gamma crystallins function by forming stable multimolecular assemblies. However, protein S possesses distinctive moth organization and domain packing, indicating a different mode of oligomerization and a divergent evolutionary pathway from the beta gamma-crystallins.