1333069-57-0Relevant articles and documents
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
supporting information, p. 5803 - 5812 (2016/07/06)
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, in Vitro Evaluation, and Radiolabeling of Fluorinated Puromycin Analogues: Potential Candidates for PET Imaging of Protein Synthesis
Betts, Helen M.,Milicevic Sephton, Selena,Tong, Carmen,Awais, Ramla O.,Hill, Philip J.,Perkins, Alan C.,Aigbirhio, Franklin I.
, p. 9422 - 9430 (2016/11/11)
There is currently no ideal radiotracer for imaging of protein synthesis rate (PSR) by positron emission tomography (PET). Existing fluorine-18-labeled amino acid-based radiotracers predominantly visualize amino acid transporter processes, and in many cases they are not incorporated into nascent proteins at all. Others are radiolabeled with the short-half-life positron emitter carbon-11, which is rather impractical for many PET centers. Based on the puromycin (6) structural manifold, a series of 10 novel derivatives of 6 was prepared via Williamson ether synthesis from a common intermediate. A bioluminescence assay was employed to study their inhibitory action on protein synthesis, which identified the fluoroethyl analogue 7b as a lead compound. The fluorine-18 analogue was prepared via nucleophilic substitution of the corresponding tosylate precursor in a modest radiochemical yield of 2 ± 0.6% with excellent radiochemical purity (>99%) and showed complete stability over 3 h at ambient temperature.
METHODS AND COMPOSITIONS FOR RIBOSOMAL SYNTHESIS OF MACROCYCLIC PEPTIDES
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Paragraph 00205, (2015/12/08)
Methods and compositions are provided for generating macrocyclic peptides from genetically encoded, ribosomally produced polypeptide precursors. Also provided are nucleic acid molecules, polypeptides, and methods for generating combinatorial libraries of
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.
Proximity-enabled protein crosslinking through genetically encoding haloalkane unnatural amino acids
Xiang, Zheng,Lacey, Vanessa K.,Ren, Haiyan,Xu, Jing,Burban, David J.,Jennings, Patricia A.,Wang, Lei
, p. 2190 - 2193 (2014/03/21)
The selective generation of covalent bonds between and within proteins would provide new avenues for studying protein function and engineering proteins with new properties. New covalent bonds were genetically introduced into proteins by enabling an unnatural amino acid (Uaa) to selectively react with a proximal natural residue. This proximity-enabled bioreactivity was expanded to a series of haloalkane Uaas. Orthogonal tRNA/synthetase pairs were evolved to incorporate these Uaas, which only form a covalent thioether bond with cysteine when positioned in close proximity. By using the Uaa and cysteine, spontaneous covalent bond formation was demonstrated between an affibody and its substrate Z protein, thereby leading to irreversible binding, and within the affibody to increase its thermostability. This strategy of proximity-enabled protein crosslinking (PEPC) may be generally expanded to target different natural amino acids, thus providing diversity and flexibility in covalent bond formation for protein research and protein engineering. Copyright
Synthesis of a cyclic peptide/protein using the NEXT-A reaction followed by cyclization
Hamamoto, Toshimasa,Sisido, Masahiko,Ohtsuki, Takashi,Taki, Masumi
, p. 9116 - 9118 (2011/10/04)
By using the NEXT-A reaction, we introduced a non-natural amino acid at the N-terminus of a peptide/protein that contained a cysteine unit. The side chain of the introduced amino acid spontaneously reacted with the cysteine to afford a cyclic peptide/protein.
