ジャーナル: Sci Rep / 年: 2016 タイトル: E. coli metabolic protein aldehyde-alcohol dehydrogenase-E binds to the ribosome: a unique moonlighting action revealed. 著者: Manidip Shasmal / Sandip Dey / Tanvir R Shaikh / Sayan Bhakta / Jayati Sengupta / 要旨: It is becoming increasingly evident that a high degree of regulation is involved in the protein synthesis machinery entailing more interacting regulatory factors. A multitude of proteins have been ...It is becoming increasingly evident that a high degree of regulation is involved in the protein synthesis machinery entailing more interacting regulatory factors. A multitude of proteins have been identified recently which show regulatory function upon binding to the ribosome. Here, we identify tight association of a metabolic protein aldehyde-alcohol dehydrogenase E (AdhE) with the E. coli 70S ribosome isolated from cell extract under low salt wash conditions. Cryo-EM reconstruction of the ribosome sample allows us to localize its position on the head of the small subunit, near the mRNA entrance. Our study demonstrates substantial RNA unwinding activity of AdhE which can account for the ability of ribosome to translate through downstream of at least certain mRNA helices. Thus far, in E. coli, no ribosome-associated factor has been identified that shows downstream mRNA helicase activity. Additionally, the cryo-EM map reveals interaction of another extracellular protein, outer membrane protein C (OmpC), with the ribosome at the peripheral solvent side of the 50S subunit. Our result also provides important insight into plausible functional role of OmpC upon ribosome binding. Visualization of the ribosome purified directly from the cell lysate unveils for the first time interactions of additional regulatory proteins with the ribosome.
Particles are selected first automatically by SPIDER and then manually by Jweb, grouped on the basis of defocus values and aligned by projection matching
CTF補正
詳細: CTF correction of 3D map
最終 再構成
想定した対称性 - 点群: C1 (非対称) / アルゴリズム: OTHER / 解像度のタイプ: BY AUTHOR / 解像度: 12.9 Å / 解像度の算出法: OTHER / ソフトウェア - 名称: SPIDER / 使用した粒子像数: 56165