BioNMR
NMR aggregator & online community since 2003
BioNMR    
Learn or help to learn NMR - get free NMR books!
 




Jobs Groups Conferences Literature Pulse sequences Software forums Programs Sample preps Web resources BioNMR issues


» Online Users: 48
0 members and 48 guests
No Members online
Most users ever online was 292, 07-25-2011 at 03:18 PM.
» Welcome!

Welcome, NMR world!


Our visitors map.


» Log in
User Name Not a member yet?
Register Now!
Password
Nanodiscs catch misfolding proteins - Xinhua
Dec 06, 2017 - 8:02 AM - by nmrlearner
nmrlearner's Avatar Nanodiscs catch misfolding proteins - Xinhua



Nanodiscs catch misfolding proteins
Xinhua
"We're able to stop the aggregation of the protein in this restricted membrane environment so we can monitor what it looks like before it becomes a mass of fibers," said lead researcher Ayyalusamy Ramamoorthy, UM professor of biophysics and chemistry ...


Read here
0 Replies | 62 Views
Cholesterol-binding site of the influenza M2 protein in lipid bilayers from solid-state NMR [Biophysics and Computational Biology]
Dec 06, 2017 - 8:02 AM - by nmrlearner
nmrlearner's Avatar Cholesterol-binding site of the influenza M2 protein in lipid bilayers from solid-state NMR [Biophysics and Computational Biology]

Matthew R. Elkins, Jonathan K. Williams, Martin D. Gelenter, Peng Dai, Byungsu Kwon, Ivan V. Sergeyev, Bradley L. Pentelute, Mei Hong...
Date: 2017-12-05

The influenza M2 protein not only forms a proton channel but also mediates membrane scission in a cholesterol-dependent manner to cause virus budding and release. The atomic interaction of cholesterol with M2, as with most eukaryotic membrane proteins, has long been elusive. We have now determined the cholesterol-binding site of... Read More


PNAS:
Number: 49
Volume: 114
0 Replies | 102 Views
[NMR paper] Direct assignment of 13C solid-state NMR signals of TFoF1 ATP synthase subunit c-ring in lipid membranes and its implication for the ring structure.
Dec 05, 2017 - 7:35 PM - by nmrlearner
nmrlearner's Avatar Direct assignment of 13C solid-state NMR signals of TFoF1 ATP synthase subunit c-ring in lipid membranes and its implication for the ring structure.

Direct assignment of 13C solid-state NMR signals of TFoF1 ATP synthase subunit c-ring in lipid membranes and its implication for the ring structure.

J Biomol NMR. 2017 Dec 02;:

Authors: Kang SJ, Todokoro Y, Bak S, Suzuki T, Yoshida M, Fujiwara T, Akutsu H

Abstract
FoF1-ATP synthase catalyzes ATP hydrolysis/synthesis coupled with a transmembrane H+ translocation in membranes. The Fo c-subunit ring plays a major role in this reaction. We have developed an assignment strategy for solid-state 13C NMR (ssNMR) signals of the Fo c-subunit ring of thermophilic Bacillus PS3 (TFo c-ring, 72 residues), carrying one of the basic folds of membrane proteins. In a ssNMR spectrum of uniformly 13C-labeled sample, the signal overlap has been a major bottleneck because most amino acid residues are hydrophobic. To overcome signal overlapping, we developed a method designated as COmplementary Sequential assignment with MInimum Labeling Ensemble (COSMILE). According to this method, we generated three kinds of reverse-labeled samples to suppress signal overlapping. To assign the carbon signals sequentially, two-dimensional C?(i+1)-C'C?(i) correlation and dipolar assisted rotational resonance (DARR) experiments were performed under magic-angle sample spinning. On the basis of inter- and intra-residue 13C-13C chemical shift correlations, 97% of C?, 97% of C? and 92% of C' signals were assigned directly from the spectra. Secondary structure analysis predicted a hairpin fold of two helices with a central loop. The effects... [Read More]
0 Replies | 52 Views
[NMR paper] Genetically encoded amino acids with tert-butyl and trimethylsilyl groups for site-selective studies of proteins by NMR spectroscopy.
Dec 05, 2017 - 7:35 PM - by nmrlearner
nmrlearner's Avatar Genetically encoded amino acids with tert-butyl and trimethylsilyl groups for site-selective studies of proteins by NMR spectroscopy.

Genetically encoded amino acids with tert-butyl and trimethylsilyl groups for site-selective studies of proteins by NMR spectroscopy.

J Biomol NMR. 2017 Dec 02;:

Authors: Loh CT, Adams LA, Graham B, Otting G

Abstract
The amino acids 4-(tert-butyl)phenylalanine (Tbf) and 4-(trimethylsilyl)phenylalanine (TMSf), as well as a partially deuterated version of Tbf (dTbf), were chemically synthesized and site-specifically incorporated into different proteins, using an amber stop codon, suppressor tRNA and the broadband aminoacyl-tRNA synthetase originally evolved for the incorporation of p-cyano-phenylalanine. The 1H-NMR signals of the tert-butyl and TMS groups were compared to the 1H-NMR signal of tert-butyltyrosine (Tby) in protein systems with molecular weights ranging from 8 to 54*kDa. The 1H-NMR resonance of the TMS group appeared near 0*ppm in a spectral region with few protein resonances, facilitating the observation of signal changes in response to ligand binding. In all proteins, the R 2 relaxation rate of the tert-butyl group of Tbf was only little greater than that of Tby (less than two-fold). Deuteration of the phenyl ring of Tbf made only a relatively small difference. The effective T 2 relaxation time of the TMS signal was longer than 140*ms even in the 54*kDa system.


PMID: 29197976 [PubMed - as supplied by publisher]



... [Read More]
0 Replies | 95 Views
[NMR paper] Selective labeling and unlabeling strategies in protein solid-state NMR spectroscopy.
Dec 05, 2017 - 7:35 PM - by nmrlearner
nmrlearner's Avatar Selective labeling and unlabeling strategies in protein solid-state NMR spectroscopy.

Selective labeling and unlabeling strategies in protein solid-state NMR spectroscopy.

J Biomol NMR. 2017 Dec 02;:

Authors: Lacabanne D, Meier BH, Böckmann A

Abstract
Selective isotope labeling is central in NMR experiments and often allows to push the limits on the systems investigated. It has the advantage to supply additional resolution by diminishing the number of signals in the spectra. This is particularly interesting when dealing with the large protein systems which are currently becoming accessible to solid-state NMR studies. Isotope labeled proteins for NMR experiments are most often expressed in E. coli systems, where bacteria are grown in minimal media supplemented with 15NH4Cl and 13C-glucose as sole source of nitrogen and carbon. For amino acids selective labeling or unlabeling, specific amino acids are supplemented in the minimal medium. The aim is that they will be incorporated in the protein by the bacteria. However, E. coli amino-acid anabolism and catabolism tend to interconnect different pathways, remnant of a subway system. These connections lead to inter conversion between amino acids, called scrambling. A thorough understanding of the involved pathways is thus important to obtain the desired labeling schemes, as not all combinations of amino acids are adapted. We present here a detailed overview of amino-acid metabolism in this context. Each amino-acid pathway is described in order to define accessible combinations for 13C or 15N specific labeling or unlabeling. Using as example the ABC transporter BmrA, a membrane protein of 600... [Read More]
0 Replies | 85 Views
[NMR paper] Studying the assembly of the BAM complex in native membranes by cellular solid-state NMR spectroscopy.
Dec 05, 2017 - 7:35 PM - by nmrlearner
nmrlearner's Avatar Studying the assembly of the BAM complex in native membranes by cellular solid-state NMR spectroscopy.

Studying the assembly of the BAM complex in native membranes by cellular solid-state NMR spectroscopy.

J Struct Biol. 2017 Nov 29;:

Authors: Pinto C, Mance D, Julien M, Daniels M, Weingarth M, Baldus M

Abstract
Significant progress has been made in obtaining a structural insight into the assembly of the ?-barrel assembly machinery complex (BAM). These crystallography and electron microscopy studies used detergent as a membrane mimetic and revealed structural variations in the central domain, BamA, as well as the lipoprotein BamC. We have used cellular solid-state NMR spectroscopy to examine the entire BamABCDE complex in native outer membranes and obtained data on the BamCDE subcomplex in outer membranes, in addition to synthetic bilayers. To reduce spectral crowding, we utilized proton-detected experiments and employed amino-acid specific isotope-labelling in (13C, 13C) correlation experiments. Taken together, the results provide insight into the overall fold and assembly of the BAM complex in native membranes, in particular regarding the structural flexibility of BamC in the absence of the core unit BamA.


PMID: 29197585 [PubMed - as supplied by publisher]



More...
0 Replies | 79 Views
[NMR] HYP18 meeting, Southampton Sep 2-5, 2018 #DNPNMR
Dec 05, 2017 - 7:35 PM - by nmrlearner
nmrlearner's Avatar From The DNP-NMR Blog:

[NMR] HYP18 meeting, Southampton Sep 2-5, 2018 #DNPNMR

This is advance notice of an international meeting on hyperpolarization, HYP18, which will be held in Southampton, UK on Sep 2-5, 2018.


The program will cover a wide range of hyperpolarization techniques and their applications, including DNP in both liquids and solids, parahydrogen-based techniques, optical pumping, quantum rotor polarization, and other methods. We hope that the meeting will promote comparison, discussion, and cross-fertilisation between the different techniques.


Confirmed speakers include:


Stephan Appelt, Aachen, Germany
Peter Blümler, Mainz, Germany
Kevin Brindle, Cambridge, UK
Arnaud Comment, Cambridge, UK
Bob Griffin, MIT, USA
Meghan Halse, York, UK
Sami Jannin, Lyon, France
Fedor Jelezko, Ulm, Germany
John Kurhanewicz, San Francisco, USA
Mathilde Lerche, Copenhagen, Denmark
Anne Lesage, Lyon, France
Gaël de Paëpe, Grenoble, France
Marek Pruski, Iowa, USA
Leif Schröder, Berlin, Germany
Thomas Theis, North Carolina, USA


Registration will open in january.
So bookmark the link: www.southampton.ac.uk/hyp18
and pencil the dates in your diaries!


Malcolm Levitt and Giuseppe Pileio


——————————————————
HYP18
Hyperpolarized Magnetic Resonance
... [Read More]
0 Replies | 134 Views
» Stats
Members: 3,202
Threads: 21,369
Posts: 21,755
Top Poster: nmrlearner (18,813)
Welcome to our newest member, bpadmanabhan
Powered by vBadvanced CMPS v3.2.2

All times are GMT. The time now is 08:26 AM.



Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
vBCredits II Deluxe v1.2.0 Copyright © 2010 DragonByte Technologies
Copyright, BioNMR.com, 2003-2013
Search Engine Friendly URLs by vBSEO 3.6.0

Map