Initial characterization of the ribosome-associated ATP binding cassette (ABC) protein YHIH from E. Coli

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Fischer, Jeffrey J.
University of Lethbridge. Faculty of Arts and Science
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Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2007
Protein synthesis is a highly conserved process across all domains of life, both structurally and functionally. This cyclic process is catalyzed by numerous soluble protein factors that interact with the ribosome to facilitate efficient protein synthesis. Many canonical translation factors bind and hydrolyze GTP to induce conformational changes that facilitate translation. For example, GTP hydrolysis by EF-Tu is required for the release of aminoacyl-tRNA into the ribosomal A site; GTP hydrolysis by EF-G facilitates the movement of tRNA and mRNA from the A site to the P site of the ribosome. However, protein synthesis seems to also have a requirement for ATP; the essential yeast protein eEF-3 facilitates release of deacyl-tRNA from the ribosomal E site. In Escherichia coli, the protein product of the open reading frame yhih has been suggested to have a similar function. However, the role of this unique prokaryotic protein is not understood. Preliminary characterization of this protein suggests a nucleotide-dependent conformational change occurs in a truncated form of the protein, ΔP541 Yhih. Interestingly, this phenomenon is not observed in ΔL432 Yhih. Both ΔP541 Yhih, and to a lesser extent ΔL432 Yhih, exhibit a ribosome-dependent ATPase activity, suggesting the primary region for binding with the ribosome lies between Leu432 and Pro541.
x, 101 leaves : ill. ; 29 cm.
Dissertations, Academic , ATP-binding cassette transporters , Escherichia coli -- Genetics , Carrier proteins , Proteins -- Synthesis