0000000000606155
AUTHOR
Giuseppe Zaccai
Harmonic behavior of trehalose-coated carbon-monoxy-myoglobin at high temperature.
Abstract Embedding biostructures in saccharide glasses protects them against extreme dehydration and/or exposure to very high temperature. Among the saccharides, trehalose appears to be the most effective bioprotectant. In this paper we report on the low-frequency dynamics of carbon monoxy myoglobin in an extremely dry trehalose glass measured by neutron spectroscopy. Under these conditions, the mean square displacements and the density of state function are those of a harmonic solid, up to room temperature, in contrast to D 2 O-hydrated myoglobin, in which a dynamical transition to a nonharmonic regime has been observed at ∼180K (Doster et al., 1989. Nature. 337:754–756). The protective ef…
Mobility of a Mononucleotide within a Lipid Matrix: A Neutron Scattering Study
International audience; An essential question in studies on the origins of life is how nucleic acids were first synthesized and then incorporated into compartments about 4 billion years ago. A recent discovery is that guided polymerization within organizing matrices could promote a non-enzymatic condensation reaction allowing the formation of RNA-like polymers, followed by encapsulation in lipid membranes. Here, we used neutron scattering and deuterium labelling to investigate 5'-adenosine monophosphate (AMP) molecules captured in a multilamellar phospholipid matrix. The aim of the research was to determine and compare how mononucleotides are captured and differently organized within matric…
A benchmark for protein dynamics: Ribonuclease A measured by neutron scattering in a large wavevector-energy transfer range
The dynamics of Ribonuclease A was explored in the full range of time and length-scales accessible by neutron spectroscopy, on time-of-flight, backscattering and spin-echo spectrometers. Samples were examined in dry and hydrated powder forms and in concentrated and dilute solutions. The aim of the study was an experimental characterisation of the full variety of protein dynamics arising from stabilisation forces. The results provide a benchmark against which other sample dynamics can be compared.