The non-H atoms of the cation of the title salt, C(8)H(9)N(4)S(+)·Cl(-), are approximately co-planar (r.m.s. deviation = 0.037 Å), with one amino group forming an intra-molecular hydrogen bond to the tertiary N atom of the benzothia-zole fused-ring system. The cations and anions are linked by cyclic R(2) (1)(6) N-H⋯Cl hydrogen-bonding associations, generating helical chains running along the b-...

Through the combination of surface sensitive photoelectron spectroscopy and molecular dynamics simulation, the relative surface propensities of guanidinium and ammonium ions in aqueous solution are characterized. The fact that the N 1s binding energies differ between these two species was exploited to monitor their relative surface concentration through their respective photoemission intensitie...

The non-H atoms of the cation of the title salt, C(8)H(9)N(4)O(+)·Cl(-), are approximately co-planar (r.m.s. deviation = 0.024 Å) with one amino group forming an intra-molecular hydrogen bond to the tertiary N atom of the benzoxazole fused-ring system. The cations and anions are linked by cyclic R(2) (1)(6) N-H⋯Cl hydrogen-bonding associations, generating linear chains running along the a-axis ...

In the crystal of the title compound, 2CH(6)N(3) (+)·2Cl(-)·C(12)H(24)O(6), the 18-crown-6 mol-ecule is located across an inversion center. The guanidinium cation links to the 18-crown-6 mol-ecule and chloride anion via N-H⋯O and N-H⋯Cl hydrogen bonds.

Chemical denaturant sensitivity of the dimeric main protease from severe acute respiratory syndrome (SARS) coronavirus to guanidinium chloride was examined in terms of fluorescence spectroscopy, circular dichroism, analytical ultracentrifuge, and enzyme activity change. The dimeric enzyme dissociated at guanidinium chloride concentration of <0.4 M, at which the enzymatic activity loss showed cl...

The hydrodynamic behavior of bovine myelin basic protein was studied by gel filtration through Sephadex G-100 under conditions which included variations in pH from 2 to 12, variations in ionic strength from 0.01 to 1.5 M at pH 2 and from 0.1 to 2 M at pH 7, and variations in guanidinium chloride concentration from 0 to 6 M. A number of well characterized compact globular proteins were subjected...

The study and successful design of coiled-coil protein structural motifs have provided much insight into the rules governing protein folding and stability. In this work we use a thermodynamic approach to quantitate the rules that govern the specific oligomerization of coiled coils. We have designed a highly stable trimeric coiled coil by placing valine residues at each a position and leucine re...

Changes in the conformational state of human plasma fibronectin and several of its fragments were studied by fluorescence emission, intrinsic fluorescence polarization and c.d. spectroscopy under conditions of guanidinium chloride-and temperature-induced unfolding. Fragments were chosen to represent all three types of internal structural homology in the protein. Low concentration (less than 2 M...

Bovine nasal cartilage was studied by electron microscopy before and after extraction with 4 M guanidinium chloride or 1 .9 M CaC12. These solvents removed matrix granules, basophilia, and 85% of the proteoglycan complex, measured as hexuronate . Simultaneously, many collagen fibrils were disaggregated into component microfibrils (approximately 40 A thick) . In contrast to the above solvents, e...