Cohesin-Dockerin Interaction in Cellulosome Assembly
Cohesin-Dockerin Interaction in Cellulosome Assembly
复制标题
纤维素体组装中的粘连蛋白-Dockerin 相互作用
DOI：
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发表时间：
2001
影响因子：
4.8
通讯作者：
E. Bayer
中科院分区：
文献类型：
--
作者：
A. Mechaly;H. Fierobe;A. Bélaich;J. Belaich;R. Lamed;Y. Shoham;E. Bayer
酶组分组装成多纤维素复合物是由粘着蛋白-锚定蛋白相互作用决定的。在最近的一篇文章（Mechaly，A.，亚伦，S.，拉米德河，巴西-地Fierobe，H.- P.，Belaich，A.，Belaich，J. P.，Shoham，Y.，Bayer，E. A.（2000）Proteins 39，170-177），我们提供了实验证据，表明四个先前预测的锚定蛋白残基在这种高亲和力相互作用的特异性中起决定性作用，尽管还涉及另外的残基。在目前的通信中，我们进一步研究的影响因素，由一个cohesin结构域之间的各自cellulosomal系统的热纤梭菌和梭菌cellulolyticum的识别的dockerin。在这种情况下，分析了四个确认的残基对选择性的单独影响。此外，其他锚定蛋白残基被认为可能有助于相互作用，并通过定点诱变对可疑残基进行了类似的修饰。结果表明，在C.热纤维素锚定蛋白通过来自C的粘蛋白区分其不识别和高亲和力识别（Ka = 109 m −1）。纤维素分解菌这表明，存在或不存在一个单一的决定性的羟基是至关重要的观察到的生物识别。这项研究进一步暗示了额外的残基作为次要决定因素的特异性的相互作用，因为所选残基的相互转换减少了种内自我识别至少三个数量级。然而，由于后者的诱变作用，以减少，但不取消该物种内的粘附蛋白-锚定蛋白的相互作用，因此，其他微妙的变化在这两个模块之间的识别中发挥相对较小的作用。
The assembly of enzyme components into the cellulosome complex is dictated by the cohesin-dockerin interaction. In a recent article (Mechaly, A., Yaron, S., Lamed, R., Fierobe, H.-P., Belaich, A., Belaich, J.-P., Shoham, Y., and Bayer, E. A. (2000)Proteins 39, 170–177), we provided experimental evidence that four previously predicted dockerin residues play a decisive role in the specificity of this high affinity interaction, although additional residues were also implicated. In the present communication, we examine further the contributing factors for the recognition of a dockerin by a cohesin domain between the respective cellulosomal systems of Clostridium thermocellum and Clostridium cellulolyticum. In this context, the four confirmed residues were analyzed for their individual effect on selectivity. In addition, other dockerin residues were discerned that could conceivably contribute to the interaction, and the suspected residues were similarly modified by site-directed mutagenesis. The results indicate that mutation of a single residue from threonine to leucine at a given position of theC. thermocellum dockerin differentiates between its nonrecognition and high affinity recognition (K a ∼ 109 m −1) by a cohesin fromC. cellulolyticum. This suggests that the presence or absence of a single decisive hydroxyl group is critical to the observed biorecognition. This study further implicates additional residues as secondary determinants in the specificity of interaction, because interconversion of selected residues reduced intraspecies self-recognition by at least three orders of magnitude. Nevertheless, as the latter mutageneses served to reduce but not annul the cohesin-dockerin interaction within this species, it follows that other subtle alterations play a comparatively minor role in the recognition between these two modules.
影响因子：
3.9
作者：
Lytle, BL;Volkman, BF;Wu, JHD
通讯作者：
Wu, JHD
影响因子：
3.5
作者：
HO, SN;HUNT, HD;PEASE, LR
通讯作者：
PEASE, LR