1434445-10-9Relevant academic research and scientific papers
Side-chain-to-tail cyclization of ribosomally derived peptides promoted by aryl and alkyl amino-functionalized unnatural amino acids
Frost, John R.,Wu, Zhijie,Lam, Yick Chong,Owens, Andrew E.,Fasan, Rudi
, p. 5803 - 5812 (2016)
A strategy for the production of side-chain-to-tail cyclic peptides from ribosomally derived polypeptide precursors is reported. Two genetically encodable unnatural amino acids, bearing either an aryl or alkyl amino group, were investigated for their efficiency toward promoting the formation of medium to large-sized peptide macrocycles via intein-mediated side-chain-to-C-terminus cyclization. While only partial cyclization was observed with precursor proteins containing para-amino-phenylalanine, efficient peptide macrocyclization could be achieved using O-2-aminoethyl-tyrosine as the reactive moiety. Conveniently, the latter was generated upon quantitative, post-translational reduction of the azido-containing counterpart, O-2-azidoethyl-tyrosine, directly in E. coli cells. This methodology could be successfully applied for the production of a 12 mer cyclic peptide with enhanced binding affinity for the model target protein streptavidin as compared to the acyclic counterpart (KD: 5.1 μM vs. 22.4 μM), thus demonstrating its utility toward the creation and investigation of novel, functional macrocyclic peptides.
Synthesis and incorporation of unnatural amino acids to probe and optimize protein bioconjugations
Maza, Johnathan C.,McKenna, Jaclyn R.,Raliski, Benjamin K.,Freedman, Matthew T.,Young, Douglas D.
, p. 1884 - 1889 (2015/09/28)
The utilization of unnatural amino acids (UAAs) in bioconjugations is ideal due to their ability to confer a degree of bioorthogonality and specificity. In order to elucidate optimal conditions for the preparation of bioconjugates with UAAs, we synthesized 9 UAAs with variable methylene tethers (2-4) and either an azide, alkyne, or halide functional group. All 9 UAAs were then incorporated into green fluorescent protein (GFP) using a promiscuous aminoacyl-tRNA synthetase. The different bioconjugations were then analyzed for optimal tether length via reaction with either a fluorophore or a derivatized resin. Interestingly, the optimal tether length was found to be dependent on the type of reaction. Overall, these findings provide a better understanding of various parameters that can be optimized for the efficient preparation of bioconjugates.
Methods and compositions for labeling polypeptides
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, (2016/04/05)
Synthesis of many proteins is tightly controlled at the level of translation and plays an essential role in fundamental processes such as cell growth and proliferation, signaling, differentiation or death. Methods that allow imaging and identification of
The genetic incorporation of thirteen novel non-canonical amino acids
Tuley, Alfred,Wang, Yane-Shih,Fang, Xinqiang,Kurra, Yadagiri,Rezenom, Yohannes H.,Liu, Wenshe R.
, p. 2673 - 2675 (2014/03/21)
Thirteen novel non-canonical amino acids were synthesized and tested for suppression of an amber codon using a mutant pyrrolysyl-tRNA synthetase-tRNAPylCUA pair. Suppression was observed with varied efficiencies. One non-canonical amino acid in particular contains an azide that can be applied for site-selective protein labeling. The Royal Society of Chemistry 2014.
