Related ArticlesDirect observation and characterization of DMPC/DHPC aggregates under conditions relevant for biological solution NMR.
Biochim Biophys Acta. 2004 Aug 30;1664(2):241-56
Authors: van Dam L, Karlsson G, Edwards K
We have used cryo-transmission electron microscopy (cryo-TEM) for inspection of aggregates formed by dimyristoylphosphatidylcholine (DMPC) and dihexanoylphosphatidylcholine (DHPC) in aqueous solution at total phospholipid concentrations cL < or = 5% and DMPC/DHPC ratios q < or = 4.0. In combination with ocular inspections, we are able to sketch out this part of phase-diagram at T = 14-80 degrees C. The temperature and the ratio q are the dominating variables for changing sample morphology, while cL to a lesser extent affects the aggregate structure. At q = 0.5, small, possibly disc-shaped, aggregates with a diameter of approximately 6 nm are formed. At higher q-values, distorted discoidal micelles that tend to short cylindrical micelles are observed. The more well-shaped discs have a diameter of around 20 nm. Upon increasing q or the temperature, long slightly flattened cylindrical micelles that eventually branch are formed. A holey lamellar phase finally appears upon further elevation of q or temperature. The implications for biological NMR work are two. First, discs prepared as membrane mimics are frequently much smaller than predicted by current "ideal bicelle" models. Second, the q approximately 3 preparations used for aligning water-soluble biomolecules in magnetic fields consist of perforated lamellar sheets. Furthermore, the discovered sequence of morphological transitions may have important implications for the development of bicelle-based membrane protein crystallization methods.
[NMR paper] Direct NMR observation of a substrate protein bound to the chaperonin GroEL.
Direct NMR observation of a substrate protein bound to the chaperonin GroEL.
Related Articles Direct NMR observation of a substrate protein bound to the chaperonin GroEL.
Proc Natl Acad Sci U S A. 2005 Sep 6;102(36):12748-53
Authors: Horst R, Bertelsen EB, Fiaux J, Wider G, Horwich AL, Wüthrich K
The reaction cycle and the major structural states of the molecular chaperone GroEL and its cochaperone, GroES, are well characterized. In contrast, very little is known about the nonnative states of the substrate polypeptide acted on by the...
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[NMR paper] Side chain NMR assignments in the membrane protein OmpX reconstituted in DHPC micelle
Side chain NMR assignments in the membrane protein OmpX reconstituted in DHPC micelles.
Related Articles Side chain NMR assignments in the membrane protein OmpX reconstituted in DHPC micelles.
J Biomol NMR. 2002 Aug;23(4):289-301
Authors: Hilty C, Fernández C, Wider G, Wüthrich K
Sequence-specific assignments have been obtained for side chain methyl resonances of Val, Leu and Ile in the outer membrane protein X (OmpX) from Escherichia coli reconstituted in 60 kDa micelles in aqueous solution. Using previously established techniques, OmpX was...
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[NMR paper] Microdrop screening: a rapid method to optimize solvent conditions for NMR spectrosco
Microdrop screening: a rapid method to optimize solvent conditions for NMR spectroscopy of proteins.
Related Articles Microdrop screening: a rapid method to optimize solvent conditions for NMR spectroscopy of proteins.
J Biomol NMR. 1998 Nov;12(4):493-9
Authors: Lepre CA, Moore JM
Determining appropriate solvent conditions is a crucial first step for carrying out NMR spectroscopy of proteins, but rapid and efficient methods for doing so are currently lacking. Microdrop screening examines a large number of different solvent conditions using...
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Direct observation of minimum-sized amyloid fibrils using solution NMR spectroscopy.
Direct observation of minimum-sized amyloid fibrils using solution NMR spectroscopy.
Related Articles Direct observation of minimum-sized amyloid fibrils using solution NMR spectroscopy.
Protein Sci. 2010 Oct 8;
Authors: Yoshimura Y, Sakurai K, Lee YH, Ikegami T, Chatani E, Naiki H, Goto Y
It is challenging to investigate the structure and dynamics of amyloid fibrils at the residue and atomic resolution due to their high molecular weight and heterogeneous properties. Here, we employed solution nuclear magnetic resonance (NMR) spectroscopy to...
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[NMR paper] Populating the equilibrium molten globule state of apomyoglobin under conditions suit
Populating the equilibrium molten globule state of apomyoglobin under conditions suitable for structural characterization by NMR.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles Populating the equilibrium molten globule state of apomyoglobin under conditions suitable for structural characterization by NMR.
FEBS Lett. 1997 Nov 3;417(1):92-6
Authors: Eliezer D, Jennings PA, Dyson HJ, Wright PE
Conditions have been determined under which the equilibrium molten globule...
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[NMR paper] 2H-NMR investigation of DMPC/glycophorin bilayers.
2H-NMR investigation of DMPC/glycophorin bilayers.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles 2H-NMR investigation of DMPC/glycophorin bilayers.
Biochim Biophys Acta. 1994 Jul 13;1193(1):127-37
Authors: Shan X, Davis JH, Chu JW, Sharom FJ
Deuterium nuclear magnetic resonance spectroscopy was used to investigate the phase equilibria, and the temperature and concentration dependences of the phospholipid hydrocarbon chain order, of mixtures of glycophorin in...
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[NMR paper] Direct observation and elucidation of the structures of aged and nonaged phosphorylat
Direct observation and elucidation of the structures of aged and nonaged phosphorylated cholinesterases by 31P NMR spectroscopy.
Related Articles Direct observation and elucidation of the structures of aged and nonaged phosphorylated cholinesterases by 31P NMR spectroscopy.
Biochemistry. 1993 Dec 14;32(49):13441-50
Authors: Segall Y, Waysbort D, Barak D, Ariel N, Doctor BP, Grunwald J, Ashani Y
31P NMR spectroscopy of butyrylcholinesterase (BChE), acetylcholinesterase (AChE), and chymotrypsin (Cht) inhibited by pinacolyl...
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[NMR paper] Direct observation of cell wall structure in living plant tissues by solid-state C NM
Direct observation of cell wall structure in living plant tissues by solid-state C NMR spectroscopy.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles Direct observation of cell wall structure in living plant tissues by solid-state C NMR spectroscopy.
Plant Physiol. 1990 Jan;92(1):61-5
Authors: Jarvis MC, Apperley DC
Solid-state (13)C nuclear magnetic resonance (NMR) spectra of the following intact plant tissues were recorded by the crosspolarization...