N-Terminal Protein Modification Using Simple Aminoacyl Transferase Substrates
摘要:
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.
Biomimetic protecting-group-free 2′, 3′-selective aminoacylation of nucleosides and nucleotides
作者:Sohyoung Her、Ronald Kluger
DOI:10.1039/c0ob00795a
日期:——
Aminoacyl phosphate monoesters can be prepared free of an amino-protecting group and used directly in lanthanum-promoted selective monoacylation of either the 2′ or 3′-hydroxyl of nucleosides and nucleotides. For example, phenylalanyl ethyl phosphate rapidly forms esters with either of the 2′ or 3′-hydroxyls of ribonucleosides and nucleotides in the presence of lanthanum ions in aqueous buffer. Oligomerization