Wang R, Alexander R W, VanLoock M, Vladimirov S, Bukhtiyarov Y, Harvey S C, Cooperman B S
Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA.
J Mol Biol. 1999 Feb 19;286(2):521-40. doi: 10.1006/jmbi.1998.2493.
Nucleotides 518-533 form a loop in ribosomal 30 S subunits that is almost universally conserved. Both biochemical and genetic evidence clearly implicate the 530 loop in ribosomal function, with respect both to the accuracy control mechanism and to tRNA binding. Here, building on earlier work, we identify proteins and nucleotides (or limited sequences) site-specifically photolabeled by radioactive photolabile oligoDNA probes targeted toward the 530 loop of 30 S subunits. The probes we employ are complementary to 16 S rRNA nucleotides 517-527, and have aryl azides attached to nucleotides complementary to nucleotides 518, 522, and 525-527, positioning the photogenerated nitrene a maximum of 19-26 A from the complemented rRNA base. The crosslinks obtained are used as constraints to revise an earlier model of 30 S structure, using the YAMMP molecular modeling package, and to place the 530 loop region within that structure.
核苷酸518 - 533在核糖体30 S亚基中形成一个环，该环几乎是普遍保守的。生化和遗传学证据均清楚地表明，530环在核糖体功能中发挥作用，涉及准确性控制机制和tRNA结合。在此，基于早期的工作，我们鉴定了被靶向30 S亚基530环的放射性光不稳定寡聚DNA探针位点特异性光标记的蛋白质和核苷酸（或有限序列）。我们使用的探针与16 S rRNA核苷酸517 - 527互补，并在与核苷酸518、522以及525 - 527互补的核苷酸上连接了芳基叠氮化物，使得光生成的氮烯与互补的rRNA碱基之间的距离最大为19 - 26埃。所获得的交联用作约束条件，使用YAMMP分子建模软件包来修正早期的30 S结构模型，并将530环区域置于该结构中。
