Protein disulfide isomerases (PDIs) are responsible for catalyzing the proper oxidation and isomerization of disulfide bonds of newly synthesized proteins in the endoplasmic reticulum (ER). The ER contains many different PDI-like proteins. Some, such as PDI, are general enzymes that directly recognize misfolded proteins while others, such as ERp57 and ERp72, have more specialized roles.
View Article and Find Full Text PDFA tetrahydroaminoquinoline-based library was generated with the goals of finding small molecule modulators of protein-protein interactions. Several library members as well as other related intermediates were tested for their ability to bind to Bcl-X(L) and Mcl-1 by in silico and (15)N NMR studies. The NMR study led to the identification of the tetrahydroaminoquinoline-based nude scaffold, 7 as a weak binder (K(d)=200 microM for Bcl-X(L) and K(d)=300 microM for Mcl-1) to both proteins.
View Article and Find Full Text PDFProtein disulfide isomerase (PDI) participates in protein folding and catalyses formation of disulfide bonds. The b' domain of human PDI contributes to binding unfolded proteins; its structure is stabilized by the b domain. Here, we report NMR chemical shift assignments for the bb' fragment.
View Article and Find Full Text PDFThe dimerization of anti-apoptotic BCL-xL by three-dimensional domain swapping has recently been discovered at alkaline pH; however, the high energetic barrier between the dimer and monomer forms of BCL-xL prevents them from interconverting at room temperature and neutral pH. Here, we demonstrate that BCL-xL dimers can be easily prepared by heating concentrated protein above 50 degrees C. The 38 kDa BCL-xL dimer was fully characterized by multi-resonance nuclear magnetic resonance (NMR) spectroscopy, and the mechanism of dimerization by alpha-helix swapping was confirmed.
View Article and Find Full Text PDFNucleosides Nucleotides Nucleic Acids
October 2004
Synthetic polycarboxamides consisting of N-methylpyrrole (Py), N-methylimidazole (Im), N-methyl-3-hydroxypyrrole (Hp) and beta-alanine (beta) show strong and sequence-specific interaction with the DNA minor groove when they form hairpin structures with side-by-side antiparallel motifs. In the present paper, new conjugates containing two ligands linked to the same terminal phosphate of DNA strand were constructed. The paper describes optimized synthesis and properties of oligonucleotide-linked polyamide strands that insert into the minor groove of a duplex in a parallel or antiparallel orientation.
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