[NMR paper] Effects of a type I antifreeze protein (AFP) on the melting of frozen AFP and AFP+solute aqueous solutions studied by NMR microimaging experiment.
Related ArticlesEffects of a type I antifreeze protein (AFP) on the melting of frozen AFP and AFP+solute aqueous solutions studied by NMR microimaging experiment.
J Biol Phys. 2013 Jan;39(1):131-44
Authors: Ba Y, Mao Y, Galdino L, Günsen Z
Abstract
The effects of a type I AFP on the bulk melting of frozen AFP solutions and frozen AFP+solute solutions were studied through an NMR microimaging experiment. The solutes studied include sodium chloride and glucose and the amino acids alanine, threonine, arginine, and aspartic acid. We found that the AFP is able to induce the bulk melting of the frozen AFP solutions at temperatures lower than 0*°C and can also keep the ice melted at higher temperatures in the AFP+solute solutions than those in the corresponding solute solutions. The latter shows that the ice phases were in super-heated states in the frozen AFP+solute solutions. We have tried to understand the first experimental phenomenon via the recent theoretical prediction that type I AFP can induce the local melting of ice upon adsorption to ice surfaces. The latter experimental phenomenon was explained with the hypothesis that the adsorption of AFP to ice surfaces introduces a less hydrophilic water-AFP-ice interfacial region, which repels the ionic/hydrophilic solutes. Thus, this interfacial region formed an intermediate chemical potential layer between the water phase and the ice phase, which prevented the transfer of water from the ice phase to the water phase. We have also attempted to understand the significance of the observed melting phenomena to the survival of organisms that express AFPs over cold winters.
TEMPOL as a polarizing agent for dynamic nuclear polarization of aqueous solutions
From The DNP-NMR Blog:
TEMPOL as a polarizing agent for dynamic nuclear polarization of aqueous solutions
Gafurov, M., TEMPOL as a polarizing agent for dynamic nuclear polarization of aqueous solutions. Magn. Reson. Solids., 2013. 15: p. 13103.
http://mrsej.ksu.ru/contents.html#13103
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05-03-2013 02:26 PM
[NMR900 blog] ICMRM-12: 12th International Conference on Magnetic Resonance Microimaging
ICMRM-12: 12th International Conference on Magnetic Resonance Microimaging
25th-29th August 2013, Fitzwilliam College, University of Cambridge, UK
The chairs and organising committee are pleased to announce the first call for abstracts for ICMRM12, to be held at Fitzwilliam College, Cambridge, UK. Detailed information about the conference and abstract submission can be found at http://www.ceb.cam.ac.uk/ICMRM12
Location The conference will be held in the historic City of Cambridge at Fitzwilliam College, one of the 28 undergraduate colleges of the University of Cambridge. The...
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03-24-2013 10:59 PM
Threonine side chain conformational population distribution of a type I antifreeze protein on interacting with ice surface studied via (13)C-(15)N dynamic REDOR NMR.
Threonine side chain conformational population distribution of a type I antifreeze protein on interacting with ice surface studied via (13)C-(15)N dynamic REDOR NMR.
Threonine side chain conformational population distribution of a type I antifreeze protein on interacting with ice surface studied via (13)C-(15)N dynamic REDOR NMR.
Solid State Nucl Magn Reson. 2011 Mar 23;
Authors: Mao Y, Jeong M, Wang T, Ba Y
Antifreeze proteins (AFPs) provide survival mechanism for species living in subzero environments by lowering the freezing points of their...
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04-08-2011 10:00 AM
[NMR paper] Diffusion of polyethyleneglycols in casein solutions and gels as studied by pulsed fi
Diffusion of polyethyleneglycols in casein solutions and gels as studied by pulsed field gradient NMR.
Related Articles Diffusion of polyethyleneglycols in casein solutions and gels as studied by pulsed field gradient NMR.
Magn Reson Imaging. 2005 Feb;23(2):347-8
Authors: Colsenet R, Soderman O, Mariette F
Molecular transport characterized by diffusion coefficients is a key feature of food processes and especially in dairy processes. Caseins represent 80% of the protein content in milk and are directly involved in the formation of dairy gels....
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11-24-2010 11:14 PM
[NMR paper] The effects of mutations on motions of side-chains in protein L studied by 2H NMR dyn
The effects of mutations on motions of side-chains in protein L studied by 2H NMR dynamics and scalar couplings.
Related Articles The effects of mutations on motions of side-chains in protein L studied by 2H NMR dynamics and scalar couplings.
J Mol Biol. 2003 Jun 6;329(3):551-63
Authors: Millet O, Mittermaier A, Baker D, Kay LE
Recently developed 2H spin relaxation experiments are applied to study the dynamics of methyl-containing side-chains in the B1 domain of protein L and in a pair of point mutants of the domain, F22L and A20V. X-ray and...
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11-24-2010 09:01 PM
[NMR paper] Relaxation of water protons in highly concentrated aqueous protein systems studied by
Relaxation of water protons in highly concentrated aqueous protein systems studied by 1H NMR spectroscopy.
Related Articles Relaxation of water protons in highly concentrated aqueous protein systems studied by 1H NMR spectroscopy.
Z Naturforsch C. 2001 Nov-Dec;56(11-12):1075-81
Authors: Szuminska K, Gutsze A, Kowalczyk A
Concentrated Aqueous Protein Systems, Proton Relaxation Times, Slow Chemical Exchange In this paper we present proton spin-lattice (T1) and spin-spin (T2) relaxation times measured vs. concentration, temperature, pulse...
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11-19-2010 08:44 PM
[NMR paper] Interaction of a type II myosin with biological membranes studied by 2H solid state N
Interaction of a type II myosin with biological membranes studied by 2H solid state NMR.
Related Articles Interaction of a type II myosin with biological membranes studied by 2H solid state NMR.
Biochemistry. 1998 Apr 21;37(16):5582-8
Authors: Arêas JA, Gröbner G, Glaubitz C, Watts A
Deuterium nuclear magnetic resonance spectroscopy (2H NMR) has been employed to investigate the interaction of lung type II myosin protein with neutral bilayers containing dimyristoylphosphatidylcholine (DMPC) as the only constituent and mixed bilayers containing...
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11-17-2010 11:06 PM
[NMR paper] NMR spectroscopy of hydroxyl protons in aqueous solutions of peptides and proteins.
NMR spectroscopy of hydroxyl protons in aqueous solutions of peptides and proteins.
Related Articles NMR spectroscopy of hydroxyl protons in aqueous solutions of peptides and proteins.
J Biomol NMR. 1992 Sep;2(5):447-65
Authors: Liepinsh E, Otting G, Wüthrich K
Hydroxyl groups of serine and threonine, and to some extent also tyrosine are usually located on or near the surface of proteins. NMR observations of the hydroxyl protons is therefore of interest to support investigations of the protein surface in solution, and knowledge of the...