Über das ätiologische Agens des Roussarkoms

Clustering of Glycine Molecules in Aqueous Solution Studied by Molecular Dynamics Simulation

“…We now assess further, on the basis of experimental data and the results of our MD simulations, the most appropriate criteria to define NH···O hydrogen bonding between glycine molecules. In the 1930s, three experimental studies of the freezing point depression of aqueous solutions of glycine – provided estimates of the average particle mass (APM) as a function of concentration. Clearly, APM values can also be determined directly from our MD simulations given a specific criterion to define NH···O hydrogen bonding between glycine molecules (and hence to define formation of glycine clusters), and here we use the comparison with the experimental results as a means of guiding our assessment of suitable hydrogen-bonding criteria to be used in the analysis of the results from our MD simulations.…”

“…Average particle masses in glycine solutions determined from our MD simulations and previous freezing point depression experiments. The experimental data are from Frankel (black crosses), Lewis (red crosses), and Anslow (blue crosses). Data from the present work are shown for several different hydrogen-bond definitions, based on the minimum NH···O angle [120° (◻), 140° (+), 160° (△)] and the maximum H···O distance [1.8 Å (purple), 2.0 Å (grey), 2.2 Å (green)].…”

“…31 The most direct experiments on the aggregation of glycine molecules in solution date back to the 1930s, when investigations on the depression of the freezing point of water due to glycine led to the conclusion that there is some degree of aggregation. [32][33][34] Due to the challenges associated with experimental studies of molecular aggregation in solution, there is a clear opportunity to exploit computer simulation techniques to provide detailed information on this issue. Recently, Campo 35 employed classical molecular dynamics simulations to study aqueous solutions of glycine at room temperature, although the main goal was not to study glycine-glycine interactions but rather to study the influence of glycine and NaCl on the surrounding water molecules.…”

“…However, direct experimental observation of such double-hydrogen-bonded dimers is difficult, and the suggestion that such dimers represent a significant species in aqueous solution has been mainly inferred from results such as atomic force microscopy of cleaved glycine surfaces, surface X-ray scattering of stereospecific adsorption of additives on glycine surfaces, and analysis of diffusion coefficients . The most direct experiments on the aggregation of glycine molecules in solution date back to the 1930s, when investigations on the depression of the freezing point of water due to glycine led to the conclusion that there is some degree of aggregation. – …”

The Crystallization, Denaturation and Flocculation of Proteins with Special Reference to Albumin and Hemoglobin; together with an Appendix on the Physicochemical Behavior of Glycine.

“…Since the above account was written a paper by M. Frankel (77) has appeared upon molecular weight determinations (boiling point as well as freezing point) for a number of amino acids in water,-in the absence of salts. Frankel finds that association is exhibited by glycine, Z-asparagin, cZ-arginine, and d-dioxyphenylalanine.…”