61781-58-6Relevant articles and documents
Homoserine and Threonine Peptide Assembly
Pirrung, Michael C.,Bakas, Nicole A.
supporting information, p. 238 - 242 (2017/11/03)
Drawing on our recent success with reagent-less peptide-bond formation through serine-based assembly reactions in organic solvent, their range has been expanded to threonine and homoserine (an aspartic acid precursor) in the N -terminal peptide. Amino aci
Native Serine Peptide Assembly – Scope and Utility
Pirrung, Michael C.,Schreihans, Ryan S.
, p. 5633 - 5636 (2016/12/14)
This work develops serine peptide assembly (SPA), which complements and contrasts with classic native chemical ligation (NCL). Advances in reagentless peptide-bond formation have been applied to serine (and serine models) and a range of C-terminal amino acids, including bulky residues that are not amenable to NCL. The particular appeal of SPA is preparative-scale segment condensations with zero racemization risk and favorable process mass intensity (PMI). Mechanistic studies support a previously proposed reaction pathway via an initial transesterification step. An understanding of the factors favoring this pathway relies on hard–soft acid–base theory, according to which mildly activated esters with the largest carbonyl positive charge are most reactive with hydroxyamines. Novel C-terminal activators have been discovered that enhance reactivity and give harmless byproducts.
Methods of modifying N-termini of a peptide or protein using transferases
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Page/Page column 20; 21, (2016/08/03)
The invention includes a selective method of modifying the N-terminus of a protein using an aminoacyl tRNA transferase. In certain embodiments, the method comprises contacting a solution of the protein or peptide with a transferase and a derivative of a molecule, whereby the N-terminus of the protein or peptide is derivatized with the molecule.
N-terminal protein modification using simple aminoacyl transferase substrates
Wagner, Anne M.,Fegley, Mark W.,Warner, John B.,Grindley, Christina L. J.,Marotta, Nicholas P.,Petersson, E. James
supporting information; experimental part, p. 15139 - 15147 (2011/11/06)
Methods for synthetically manipulating protein structure enable greater flexibility in the study of protein function. Previous characterization of the Escherichia coli aminoacyl tRNA transferase (AaT) has shown that it can modify the N-terminus of a protein with an amino acid from a tRNA or a synthetic oligonucleotide donor. Here, we demonstrate that AaT can efficiently use a minimal adenosine substrate, which can be synthesized in one to two steps from readily available starting materials. We have characterized the enzymatic activity of AaT with aminoacyl adenosyl donors and found that reaction products do not inhibit AaT. The use of adenosyl donors removes the substrate limitations imposed by the use of synthetases for tRNA charging and avoids the complex synthesis of an oligonucleotide donor. Thus, our AaT donors increase the potential substrate scope and reaction scale for N-terminal protein modification under conditions that maintain folding.
The BF3·OEt2-assisted conversion of nitriles into thioamides with Lawesson's reagent
Nagl, Michael,Panuschka, Claudia,Barta, Andrea,Schmid, Walther
experimental part, p. 4012 - 4018 (2009/05/27)
A method for the thiolysis of nitriles by applying Lawesson's reagent and facilitated by the addition of boron trifluoride-diethyl ether complex is reported. The method opens an easy access to primary thioamides. Aromatic, benzylic, and aliphatic nitriles were converted into the corresponding thioamides in high to quantitative yields (even in unfavorable cases, e.g., ortho-substitut-ed benzonitriles). The reaction was performed in 1,2-dimethoxyethane-tetrahydrofuran or toluene-diethyl ether solvent mixtures at 20-50°C, and exhibited considerable selectivity in the case of multifunctional nitrile substrates, such as cyanomethyl N-acetylphenylalaninate, benzoylacetonitrile, 4-cyanobenzamide, 4-acetylbenzonitrile, or pent-3-enenitrile. Georg Thieme Verlag Stuttgart.
