Ubiquitin signaling in eukaryotes is responsible for a variety of cellular outcomes, most notably proteasomal degradation. A recent bioinformatic study has revealed the existence of a new proteasomal operon in certain gram-negative bacteria phyla. This operon contains genes similar to those included in the prokaryotic ubiquitin-like protein (Pup) proteasomal operon, but do not themselves contain Pup. Instead, they encode for a protein termed UBact with 30% sequence similarity to Pup. Here, we...
HACANCOi: a new H α -detected experiment for backbone resonance assignment of intrinsically disordered proteins
HACANCOi: a new H α -detected experiment for backbone resonance assignment of intrinsically disordered proteins
Abstract
Unidirectional coherence transfer is highly efficient in intrinsically disordered proteins (IDPs). Their elevated ps-ns timescale dynamics ensures long transverse (T2) relaxation times allowing sophisticated coherence transfer pathway selection in comparison to folded proteins. 1Hα-detection ensures non-susceptibility to chemical exchange with the solvent and enables chemical shift assignment of consecutive proline residues,...
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10-29-2020 10:21 AM
Dispersion from C α or N H : 4D experiments for backbone resonance assignment of intrinsically disordered proteins
Dispersion from C α or N H : 4D experiments for backbone resonance assignment of intrinsically disordered proteins
Abstract
Resonance assignment of intrinsically disordered proteins is remarkably challenging due to scant chemical shift dispersion arising from conformational heterogeneity. The challenge is even greater if repeating segments are present in the amino acid sequence. To forward unambiguous resonance assignment of intrinsically disordered proteins, we present iHACANCO, HACACON and (HACA)CONCAHA, three Hα-detected 4D experiments with Cα...
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02-29-2020 09:52 PM
Five and four dimensional experiments for robust backbone resonance assignment of large intrinsically disordered proteins: application to Tau3x protein
Five and four dimensional experiments for robust backbone resonance assignment of large intrinsically disordered proteins: application to Tau3x protein
Abstract
New experiments dedicated for large IDPs backbone resonance assignment are presented. The most distinctive feature of all described techniques is the employment of MOCCA-XY16 mixing sequences to obtain effective magnetization transfers between carbonyl carbon backbone nuclei. The proposed 4 and 5 dimensional experiments provide a high dispersion of obtained signals making them suitable for use...
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07-20-2016 08:15 AM
Amino acid recognition for automatic resonance assignment of intrinsically disordered proteins
Amino acid recognition for automatic resonance assignment of intrinsically disordered proteins
Abstract
Resonance assignment is a prerequisite for almost any NMR-based study of proteins. It can be very challenging in some cases, however, due to the nature of the protein under investigation. This is the case with intrinsically disordered proteins, for example, whose NMR spectra suffer from low chemical shifts dispersion and generally low resolution. For these systems, sequence specific assignment is highly time-consuming, so the prospect of using...
A six-dimensional alpha proton detection-based APSY experiment for backbone assignment of intrinsically disordered proteins
A six-dimensional alpha proton detection-based APSY experiment for backbone assignment of intrinsically disordered proteins
Abstract
Sequence specific resonance assignment is the prerequisite for the NMR-based analysis of the conformational ensembles and their underlying dynamics of intrinsically disordered proteins. However, rapid solvent exchange in intrinsically disordered proteins often complicates assignment strategies based on HN-detection. Here we present a six-dimensional alpha proton detection-based automated projection spectroscopy (APSY)...
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11-04-2014 01:02 AM
High dimensional and high resolution pulse sequences for backbone resonance assignment of intrinsically disordered proteins
High dimensional and high resolution pulse sequences for backbone resonance assignment of intrinsically disordered proteins
Abstract Four novel 5D (HACA(N)CONH, HNCOCACB, (HACA)CON(CA)CONH, (H)NCO(NCA)CONH), and one 6D ((H)NCO(N)CACONH) NMR pulse sequences are proposed. The new experiments employ non-uniform sampling that enables achieving high resolution in indirectly detected dimensions. The experiments facilitate resonance assignment of intrinsically disordered proteins. The novel pulse sequences were successfully tested using δ subunit (20 kDa) of Bacillus subtilis RNA polymerase...
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02-21-2012 03:40 AM
HA-detected experiments for the backbone assignment of intrinsically disordered prote
Abstract We propose a new alpha proton detection based approach for the sequential assignment of natively unfolded proteins. The proposed protocol superimposes on following features: HA-detection (1) enables assignment of natively unfolded proteins at any pH, i.e., it is not sensitive to rapid chemical exchange undergoing in natively unfolded proteins even at moderately high pH. (2) It allows straightforward assignment of proline-rich polypeptides without additional proline-customized experiments. (3) It offers more streamlined and less ambiguous assignment based on solely intraresidual...
Backbone NMR resonance assignment of the intrinsically disordered UBact protein from Nitrospira nitrosa
Linear Mode
