NMR investigation of frozen porcine muscle

Duff, I.D; Derbyshire, W.

doi:10.1016/0022-2364(74)90084-5

Cited by 7 publications

(6 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Before dealing with particular examples we should note that a great deal of evidence, some of which is admittedly somewhat circumstantial, supports the view that a fraction of the water in heterogeneous and biological systems has properties quite distinct from those of bulk water. For example, it is a well established fact that in such systems as solutions of polysaccharides (Duff & Derbyshire 1975) and proteins (Kuntz 1971;Kuntz, Brassfield, Law & Purcell 1969) and in tissues (Duff & Derbyshire 1974;Belton, Packer & Sellwood 1973;Fung, Durham & Wassil 1975) a fraction of the water, amounting to approximately 0.3-0.6 g water/g nonaqueous component, does not freeze and remains unfrozen to temperatures below 200 K. More detailed discussions of this and related evidence are given in the reviews mentioned above (Cooke & Kuntz 1974;Kuntz & Kauzmann 1974) and below.…”

Section: Studies Of Water Dynamics In Heterogeneous Systemsmentioning

confidence: 99%

“…As was demonstrated by Kuntz (1969Kuntz ( , 1971 cooling of many biological systems below the freezing point of ice leaves a fraction of the water which remains mobile. This is evidenced by its giving a relatively sharp (T 2 1 ms) X H resonance spectrum (7 fo Several groups of workers have studied the proton relaxation behaviour of this non-freezing water in a number of systems such as striated muscle (Belton et al 1973;Duff & Derbyshire 1974;Fung et al 1975), hydrated collagen (Fung, Witschel & McAmis 1974), cornea (Bruynooghe & Packer 1975 and agarose gels (Duff & Derbyshire 1975). A typical set of results is shown in figure 10.…”

Section: (B) Non-freezing Watermentioning

confidence: 99%

“…A 7 \minimum, dependent on oj0, is observed and it is found that a single correlation time model is quite inadequate to represent the temperature and frequency dependence of 7 In several cases (Duff & Derbyshire 1974, 1965Belton et al 1973;Fung et al 1974Fung et al ? 1975 a log-normal distribution of correlation times (Resing 1965) has been found to represent the data although the calculated dipolar coupling strength (i.e.…”

Section: (B) Non-freezing Watermentioning

confidence: 99%

“…Q\ in equation ( 3)) is smaller than that arising from even the intramolecular proton-proton interaction in water and the values of T' a, calculated from the distribution parameters characterizing 7\, are an order of magnitude larger than those observed. There are a variety of possible explanations of these facts and it may be that each effect which has been discussed contributes but it seems likely (i) that there is a number or distribution of correlation times determining Tx and these may arise because of the intrinsically anisotropic rotation of the bound water and/or because of the existence of binding sites with differing characteristics, (ii) that around 250 K the mean correlation time governing Tx is of the order of 2 x 10~9 s and (iii) that because Tlp (mx ~ 0.5 x 106 rad s-1) is equal to T2 for the protons in the non-freezing water in muscle (Duff & Derbyshire 1974) but is inter mediate in value between Tx and T2 in the frozen agarose/water system (Duff & Derbyshire 1975), the extra contribution to T2a rises from a process with a correlation time o 10-6 s and is probably one or more of those described in figure 6 by the correlation times r e, 7' and 7". Note that again the correlation time 7' for the reorientation of the bound water is of the order of 10~9 s. There is direct evidence for the existence of dynamically oriented water in striated muscle from 2H n.m.r.…”

Section: (B) Non-freezing Watermentioning

confidence: 99%

See 3 more Smart Citations

The dynamics of water in heterogeneous systems

Packer

1977

Phil. Trans. R. Soc. Lond. B

108

View full text Add to dashboard Cite

The basic principles of nuclear spin relaxation, dielectric relaxation and quasielastic neutron scattering and their use in studying the motions of water molecules are outlined. A summary is given of the time scales associated with the translational and rotational motions of water molecules and of intermolecular proton exchange in pure liquid water. A model is then proposed for the dynamics of water molecules in heterogeneous systems involving regions having differing compositions, water molecules within each region existing in environments both affected by interaction with the macromolecular components and free of their influence and including exchange of water molecules between different environments and regions. The lifetime of the interaction of water molecules with the macromolecular components is assumed long compared with the time for rotation of such bound molecules. Exchange of protons between water molecules and between water molecules and macromolecules is also considered. The ways in which such processes would be expected to affect the observed nuclear magnetic resonance, dielectric and neutron scattering behaviour are outlined. Particular emphasis is placed on nuclear spin relaxation phenomena and the existence and observation of residual dipolar and quadrupolar splittings in the n.m.r. spectra of 1 H and 2 H (D) nuclei in water molecules in such systems, these splittings arising from water molecules dynamically oriented at water/macromolecule interfaces. Details are then given of particular studies of water molecule dynamics in heterogeneous systems using n.m.r., dielectric and neutron scattering techniques. The systems discussed include moist protein powders, protein solutions, phospholipid/ water and soap/water mesophases, clay/water systems and biological polymers and tissues. It is concluded that water in these systems is highly mobile, that water molecules affected directly by a macromolecule tumble anisotropically about all axes relative to the macromolecule with correlation times in the region of 10 -9 s at 260 K and that these molecules exchange with water molecules free of the influence of the macromolecule with a lifetime in the dynamically oriented state of the order of 10 -6 s at temperatures around 300 K. The ability of nuclear magnetic relaxation studies to distinguish water in different regions of a tissue is discussed and examples are given of the study of the rate of water transport across membranes using these techniques.

show abstract

Section: Studies Of Water Dynamics In Heterogeneous Systemsmentioning

confidence: 99%

Section: (B) Non-freezing Watermentioning

confidence: 99%

Section: (B) Non-freezing Watermentioning

confidence: 99%

Section: (B) Non-freezing Watermentioning

confidence: 99%

See 2 more Smart Citations

The dynamics of water in heterogeneous systems

Packer

1977

Phil. Trans. R. Soc. Lond. B

108

View full text Add to dashboard Cite

show abstract

“…The motion of water molecules in the cell is rather complex due to the interaction of water with the proteins and other macromolecules as well as cellular organelles leading to a distribution of correlation times characterizing the motion of water molecules in the cell (2,19,(37)(38)(39)(40). The motion of water molecules interacting with the cellular components is considered to be anisotropic in protein crystals (19) and other heterogeneous systems such as aqueous solutions of macromolecules, whole cells, and tissues (36, 43-45, 49, 50 dependence.…”

Section: Theoretical Backgroundmentioning

confidence: 99%

Intracellular water in Artemia cysts (brine shrimp)

Kasturi¹,

Seitz²,

Chang³

et al. 1990

Biophysical Journal

View full text Add to dashboard Cite

The dormant cysts of Artemia undergo cycles of hydration-dehydration without losing viability. Therefore, Artemia cysts serve as an excellent intact cellular system for studying the dynamics of water-protein interactions as a function of hydration. Deuterium spin-lattice (T(1)) and spin-spin (T(2)) relaxation times of water in cysts hydrated with D(2)O have been measured for hydrations between 1.5 and 0.1 g of D(2)O per gram of dry solids. When the relaxation rates (I/T(1), I/T(2)) of (2)H and (17)O are plotted as a function of the reciprocal of hydration (1/H), an abrupt change in slope is observed near 0.6 g of D(2)O (or H(2) (17)O)/gram of dry solids, the hydration at which conventional metabolism is activated in this system. The results have been discussed in terms of the two-site and multisite exchange models for the water-protein interaction as well as protein dynamics models. The (2)H and (17)O relaxation rates as a function of hydration show striking similarities to those observed for anisotropic motion of water molecules in protein crystals.It is suggested here that although the simple two-site exchange model or n-site exchange model could be used to explain our data at high hydration levels, such models are not adequate at low hydration levels (<0.6 g H(2)O/g) where several complex interactions between water and proteins play a predominant role in the relaxation of water nuclei. We further suggest that the abrupt change in the slope of I/T(1) as a function of hydration in the vicinity of 0.6 g H(2)O/g is due to a change in water-protein interactions resulting from a variation in the dynamics of protein motion.

show abstract

NMR relaxation of spin‐3/2 nuclei: Effects of structure, order, and dynamics in aqueous heterogeneous systems

Woessner

2001

Concepts Magn. Reson.

104

View full text Add to dashboard Cite

ABSTRACT:The mathematical expressions for interpreting the results of spin-lattice relaxation, transverse relaxation, spin-lattice relaxation in the rotating frame, and Ostroff ᎐ 3 Waugh multiple-pulse sequence relaxation experiments on spin-nuclei with electric 2 quadrupole interaction in an isotropic environment are biexponential. A protocol for applying these expressions to investigate quadrupole interactions and ionic motions in complex aqueous heterogeneous systems such as biopolymer gels and biological tissue is described. Experimental evidence for at least two different environments for hydrated sodium ions, including an isotropic liquid aqueous phase and an anisotropic interfacial phase at the macromolecules, is reviewed. The use of the basic equations and experimental protocol are illustrated for systems of increasing complexity, ranging from simple NaCl aqueous solutions, highly concentrated agarose gels, gelatin gels, and gellan gels to xanthan gels that contain ordered macromolecules. Many different experiments on various biopolymer samples indicate a correlation time of approximately 1 ns for ions at the interface that dominates in determining spin-lattice relaxation and also the long component of the transverse relaxation that arises from the central transitions. The transverse relaxation of the satellite transitions is dominated by much longer correlation times that may be related to the geometry of the macromolecular matrix in which the hydrated aqueous sodium ions diffuse. In the case of xanthan, the macromolecular ordering causes residual quadrupolar splitting and enables the measurement of several very long correlation times.One of these appears to agree with the Kuhn length of xanthan that was determined by light scattering experiments on dilute solutions.

show abstract

NMR investigation of frozen porcine muscle

Cited by 7 publications

References 16 publications

The dynamics of water in heterogeneous systems

The dynamics of water in heterogeneous systems

Intracellular water in Artemia cysts (brine shrimp)

NMR relaxation of spin‐3/2 nuclei: Effects of structure, order, and dynamics in aqueous heterogeneous systems

Contact Info

Product

Resources

About