Nikulin Alexei, Eliseikina Irina, Tishchenko Svetlana, Nevskaya Natalia, Davydova Natalia, Platonova Olga, Piendl Wolfgang, Selmer Maria, Liljas Anders, Drygin Denis, Zimmermann Robert, Garber Maria, Nikonov Stanislav
Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia.
Nat Struct Biol. 2003 Feb;10(2):104-8. doi: 10.1038/nsb886.
The L1 protuberance of the 50S ribosomal subunit is implicated in the release/disposal of deacylated tRNA from the E site. The apparent mobility of this ribosomal region has thus far prevented an accurate determination of its three-dimensional structure within either the 50S subunit or the 70S ribosome. Here we report the crystal structure at 2.65 A resolution of ribosomal protein L1 from Sulfolobus acidocaldarius in complex with a specific 55-nucleotide fragment of 23S rRNA from Thermus thermophilus. This structure fills a major gap in current models of the 50S ribosomal subunit. The conformations of L1 and of the rRNA fragment differ dramatically from those within the crystallographic model of the T. thermophilus 70S ribosome. Incorporation of the L1-rRNA complex into the structural models of the T. thermophilus 70S ribosome and the Deinococcus radiodurans 50S subunit gives a reliable representation of most of the L1 protuberance within the ribosome.
50S核糖体亚基的L1突出部与脱酰基tRNA从E位点的释放/清除有关。该核糖体区域明显的流动性迄今阻碍了对其在50S亚基或70S核糖体中三维结构的精确测定。在此，我们报道了嗜酸嗜热栖热菌核糖体蛋白L1与嗜热栖热菌23S rRNA特定55核苷酸片段复合物的2.65埃分辨率晶体结构。该结构填补了当前50S核糖体亚基模型中的一个主要空白。L1和rRNA片段的构象与嗜热栖热菌70S核糖体晶体学模型中的构象有显著差异。将L1-rRNA复合物纳入嗜热栖热菌70S核糖体和耐辐射球菌50S亚基的结构模型中，能可靠地呈现核糖体中大部分L1突出部。
