Guanine nucleotides stabilize the binding of Bacillus subtilis Obg to ribosomes.
Guanine nucleotides stabilize the binding of Bacillus subtilis Obg to ribosomes.
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DOI：
10.1016/j.bbrc.2004.07.154
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发表时间：
2004-09
影响因子：
3.1
通讯作者：
Shuyu Zhang;W. Haldenwang
中科院分区：
文献类型：
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作者：
Shuyu Zhang;W. Haldenwang
Obg是枯草芽孢杆菌的GTP结合蛋白，在细菌的生长、孢子形成和应激反应中具有重要但不确定的作用。Obg同源基因在细菌和真核生物中广泛保守。凝胶过滤和亲和印迹分析表明，OBG可能是核糖体相关的。在目前的工作中，我们继续检查假定的Obg：核糖体相互作用。粗B的速度离心分析。枯草杆菌提取物或纯化的Obg：核糖体混合物表明，Obg最初是核糖体结合的，但在不存在添加的核苷酸的情况下，可以在沉降过程中与核糖体分离。此外，无论是GTP，GDP或ATP的梯度延长OBG：核糖体协会，而列入nonhydrolyzable GTP类似物（5-guanylyl-imidodiphosphate）保存it. The数据加强的概念，OBG是一个核糖体相关蛋白，证明OBG的协会与核糖体稳定的GTP，并表明核糖体结合OBG可能水解GTP和被释放的结果。
Obg is a GTP-binding protein of Bacillus subtilis with essential, but undefined roles in the bacterium’s growth, sporulation, and stress responses. Obg orthologs are widely conserved among both bacteria and eukaryotes. Gel filtration and affinity blot assays have suggested that Obg may be ribosome-associated. In the current work, we continue an examination of the putative Obg:ribosome interaction. Velocity centrifugation analyses of crude B. subtilis extracts or purified Obg:ribosome mixtures suggest that Obg is initially ribosome-bound, but can separate from ribosomes during sedimentation in the absence of added nucleotides. Addition of either GTP, GDP or ATP to the gradient prolonged the Obg:ribosome association, while inclusion of a nonhydrolyzable GTP analog (5-guanylyl-imidodiphosphate) preserved it. The data strengthen the notion that Obg is a ribosome-associated protein, demonstrate that Obg’s association with ribosomes is stabilized by GTP, and indicate that the ribosome-bound Obg can likely hydrolyze GTP and be released as a consequence.