Search for dissertations about: "Peptide bond formation"
Showing result 11 - 15 of 33 swedish dissertations containing the words Peptide bond formation.
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11. Rate and Accuracy of Bacterial Protein Synthesis with Natural and Unnatural Amino Acids
Abstract : This thesis addresses different questions regarding the rate, efficiency, and accuracy of peptide bond formation with natural as well as unnatural amino acids: Which step is rate-limiting during peptide bond formation? How does the accuracy vary with different transfer RNAs (tRNAs) and codons and how is it relevant to the living cells? Does proofreading selection of codon reading occur in a single- or multi-step manner as theoretically suggested? How does the E. coli translation system discriminate unnatural amino acids? Based on that, how to improve the incorporation efficiencies of unnatural amino acids?Based on the study on pH dependence of peptide bond formation, we show that the rate of the chemistry of peptidyl transfer to aminoacyl-tRNA (AA-tRNA) Gly-tRNAGly or Pro-tRNAPro limits the rate of peptide bond formation at physiological pH 7. READ MORE
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12. Metallocene based peptidomimetics and chiral catalysts
Abstract : Several optically active organometallic Phe-AAn-Phe peptidomimetics and macrocyclic Phe-(Phe)n peptides have been synthesized by either intra- or intermolecular peptide bond formation of the corresponding bis(amino acid) derivatives. The key bis(amino acid) derivatives were available from an improved multi-step synthetic route, utilising Horner-Wadswort-Emmons olefination of organometallic aldehydes with phosphonylglycine reagents, enantioselective hydrogenation of didehydro amino acids and classical solution and/or solid phase peptide synthesis methodology. READ MORE
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13. Mechanism and Regulation of Initiation of Protein Synthesis in Eubacteria
Abstract : Initiation of protein synthesis in E.coli involves several steps, which lead to the formation of the first peptide bond. This process requires three initiation factors: IF1, IF2 and IF3. READ MORE
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14. Surface modification of cellulose materials : from wood pulps to artificial blood vessels
Abstract : This thesis describes the improvement of two radically different cellulose materials, paper and artificial blood vessels, constructed from two diverse cellulose sources, wood pulp and Acetobacter xylinum. The improvement of both materials was possible due to the natural affinity of the hemicellulose xyloglucan for cellulose. READ MORE
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15. Rate and Accuracy of Bacterial Protein Synthesis
Abstract : High levels of accuracy in transcription, aminoacylation of tRNA, and mRNA translation are essential for all life forms. However, high accuracy also necessarily means large energy dissipation and slow kinetics. Therefore, in vivo there is a fine tuned balance between rate and accuracy of key chemical reactions. READ MORE