Reference

Effect of solvent polarity on interaction of similar and dissimilar dye molecules

Effect of solvent polarity on interaction of similar and dissimilar dye molecules. Ryzhikov, B. D.; Savel'ev, V. P. (USSR). Mater. Vses. Soveshch. Fiz. Zhidk., 10th, Meeting Date 1974, 128-36. Edited by: Atakhodzhaev, A. K. Samark. Gos. Univ.: Samarkand, USSR. (Russian) 1975. CODEN: 37ALAN. DOCUMENT TYPE: Conference CA Section: 40 (Dyes, Fluorescent Whitening Agents, and Photosensitizers) The solvent effect on the assocn. of dyes in soln. was attributed to the solvate envelope around the dye mols. With increasing concn. of Rhoduline Yellow (I) [2390-54-7] aq. solns. from 3 ′ 10-6 to ~10-4 g/mL the absorption peak at 415 nm decreased in intensity, and with further concn. increase to 10-2 g/mL shifted to 395 nm. The luminescence intensity of such solns. decreased with increasing concn., with eventual appearance of a new luminescence at longer wavelength. These effects were not obsd. in other polar solvents at room temp., but similar effects in acetone soln. could be induced by lowering the temp. Analogous effects on luminescence were obsd. for solns. of I and Acridine Orange NO (II) [65-61-2] in pyridine, PhCH2OH, CHCl3, and their binary mixts. with CCl4; bonding energies of the assocd. mols. decreased with decreasing solvent polarity. The mutual assocn. of II with methyl blue (III) [28983-56-4] (a thiazine dye) in aq. soln. at 17° was shown spectroscopically: the absorption peaks due to II (492 nm) and III (664 nm) decreased in intensity as the concn. of II was increased from 10-6 to 9.6 ′ 10-5 g/mL at a const. III concn. of 10-6 g/mL.

Mass spectroscopic analysis of Sup35NM prion polymerization

Mass spectroscopic analysis of Sup35NM prion polymerization. Goncharov, Vladimir A. (Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA). Biophysical Journal, 89(6), 4139-4148 (English) 2005 Biophysical Society. CODEN: BIOJAU. ISSN: 0006-3495. DOCUMENT TYPE: Journal CA Section: 6 (General Biochemistry) Sup35NM, the prion detg. domain of the protein responsible for the yeast prion phenomenon [Y], has become a powerful model for studying key processes in amyloid-related human diseases. One of these processes is a conformational conversion of sol. precursor protein into insol. fibrillar structures. In this study, we created a set of Sup35NM mutants and used proteolytic digestion coupled with mass spectroscopy to monitor local structure of the protein during polymn. Exptl. data were compared to a network model and showed that during the conformational conversion residue Arg-28 became highly protected from cleavage, residue Arg-98 remained partially solvent exposed, and residues between 28 and 98 showed an intermediate degree of protection. In addn., we found that a distinct subset of proteolytic polypeptides spanning 28-98 residues segment spontaneously formed stable dimers. This finding suggests that the [29-98] region is the key interacting region of Sup35NM responsible for amyloid conversion.Except for chemicals metioned above, 2390-54-7 and 74-79-3 are also used. .