Proton spin-lattice relaxation in silkworm cocoons: physisorbed water and serine side-chain motions

The Journal of Physical Chemistry. B
Marco GeppiSilvia Cappellozza

Abstract

The molecular dynamic behavior of silkworm cocoons produced by a single Bombyx mori strain was investigated by means of high- and low-resolution solid-state NMR experiments. Cocoons with different moisture content were prepared to study the effects of physisorbed water on their molecular dynamics in the MHz regime, which was probed through the measurement of (1)H T(1) relaxation times at 25 MHz in the 25-95 degrees C temperature range. The water content of the different samples was determined from the analysis of (1)H free-induction decays. In addition to the rotation of methyl groups, mostly from alanine, and to the reorientation of physisorbed water molecules, already identified in previous works as relaxation sinks, the reorientation of serine side-chains was here found to contribute to (1)H T(1) above room temperature. The analysis of the trends of (1)H T(1) versus temperature was carried out in terms of semiempirical models describing the three main motional processes, and indicated that methyl rotation, water reorientation and serine side-chain motions are the most efficient relaxation mechanisms below 0 degrees C, between 0 and 60 degrees C, and above 60 degrees C, respectively. The activation energies were found to decr...Continue Reading

References

Jan 1, 1984·Annual Review of Biophysics and Bioengineering·D A Torchia
Nov 1, 1996·Solid State Nuclear Magnetic Resonance·A M Kenwright, B J Say
Nov 10, 1998·Solid State Nuclear Magnetic Resonance·M GeppiB J Say
Jul 13, 2002·Biopolymers·A I KishoreF Separovic
Jun 19, 2003·Journal of the American Chemical Society·Terry GullionTetsuo Asakura
Sep 6, 2003·International Journal of Biological Macromolecules·Lucia CalucciSilvia Ghiringhelli
Jan 28, 2004·Magnetic Resonance in Chemistry : MRC·Detlef ReichertDaniel Huster
Jul 13, 2004·Biomacromolecules·Lucia CalucciGiulia Mollica

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Citations

Apr 11, 2012·International Journal of Pharmaceutics·Sarah P HudsonPeter McLoughlin
Jun 26, 2014·Scientific Reports·Brindan TulachanMainak Das
Mar 8, 2011·Chemphyschem : a European Journal of Chemical Physics and Physical Chemistry·Elisa CarignaniMarco Geppi
Jul 13, 2011·The Journal of Physical Chemistry. a·Elisa CarignaniMarco Geppi

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