A protein residing at the subunit interface of the bacterial ribosome
A protein residing at the subunit interface of the bacterial ribosome
复制标题
DOI：
10.1073/pnas.96.22.12345
复制
发表时间：
1999-10-26
影响因子：
11.1
通讯作者：
Spirin, AS
中科院分区：
文献类型：
--
作者：
Agafonov, DE;Kolb, VA;Spirin, AS
利用氚轰击技术对大肠杆菌核糖体进行表面标记，发现了隐藏在70S核糖体中的少量未识别的核糖体结合蛋白（Y点），并在70S核糖体解离成亚基时被高度标记。本研究确定了Y蛋白的n端序列，并鉴定其基因为yfia，是位于大肠杆菌反操纵子上游的一个ORF。该蛋白为12.7 kda，经分离鉴定。纯化蛋白Y对30S亚基有亲和力，但对50S核糖体亚基没有亲和力。该蛋白被证明暴露在30S亚基的表面。50S亚基的附着导致Y蛋白被隐藏，从而提示蛋白位于70S核糖体的亚基界面。该蛋白被证明可以稳定核糖体以防止解离。讨论了蛋白Y作为核糖体结合因子在翻译中的可能作用。
Surface labeling of Escherichia coli ribosomes with the use of the tritium bombardment technique has revealed a minor unidentified ribosome-bound protein (spot Y) that is hidden in the 70S ribosome and becomes highly labeled on dissociation of the 70S ribosome into subunits. In the present work, the N-terminal sequence of the protein Y was determined and its gene was identified as yfia, an ORF located upstream the phe operon of E. coli. This 12.7-kDa protein was isolated and characterized. An affinity of the purified protein Y for the 30S subunit, but not for the 50S ribosomal subunit, was shown. The protein proved to be exposed on the surface of the 30S subunit. The attachment of the 50S subunit resulted in hiding the protein Y, thus suggesting the protein location at the subunit interface in the 70S ribosome. The protein was shown to stabilize ribosomes against dissociation. The possible role of the protein Y as ribosome association factor in translation is discussed.