The C-Terminal O-S Acyl Shift Pathway under Acidic Condition to Propose Peptide-Thioesters

The C-Terminal O-S Acyl Shift Pathway under Acidic Condition to Propose Peptide-Thioesters.

Peptide-thioester is a pivotal intermediate for peptide ligation and N-, C-terminal cyclization. In this study, desired pathway and the side products of two C-terminal handles, hydroxyethylthiol (HET) and hydroxypropylthiol (HPT) are described in different conditions as well as kinetic studies. In addition, a new mechanism of C-terminal residue racemization is proposed on the basis of different...

Fmoc-Compatible Solid Phase Peptide Synthesis of Long C-Terminal Peptide Thioesters

Biomimetic synthesis of cyclic peptides using novel thioester surrogates.

Acyl shifts involving N-S and S-S rearrangements are reactions central to the breaking of a peptide bond and forming of thioester intermediates in an intein-catalyzed protein splicing that ultimately leads to the formation of a new peptide bond by an uncatalyzed S-N acyl shift reaction. To mimic these three acyl shift reactions in forming thioesters and the subsequent peptide ligation, here we ...

Universality under Szegő ’ s condition ∗

This paper presents a theorem on universality on orthogonal polynomials/random matrices under a weak local condition on the weight function w. With a new inequality for polynomials and with the use of fast decreasing polynomials, it is shown that an approach of D. S. Lubinsky is applicable. The proof works at all points which are Lebesgue-points both for the weight function w and for logw.

Acidic C-terminal domains autoregulate the RNA chaperone Hfq

The RNA chaperone Hfq is an Sm protein that facilitates base pairing between bacterial small RNAs (sRNAs) and mRNAs involved in stress response and pathogenesis. Hfq possesses an intrinsically disordered C-terminal domain (CTD) that may tune the function of the Sm domain in different organisms. In Escherichia coli, the Hfq CTD increases kinetic competition between sRNAs and recycles Hfq from th...