Dissecting the Membrane Association Mechanism of Aerolysin Pores at Femtomolar Concentrations Using Water as a Probe.

Aerolysin is a bacterial toxin that forms transmembrane pores at the host plasma membrane and has a narrow internal diameter and great stability. These assets make it a highly promising nanopore for detecting biopolymers such as nucleic acids and peptides. Although much is known about aerolysin from a microbiological and structural perspective, its membrane association and pore-formation mechanism are not yet fully understood.

Liposomes and Lipid Droplets Display a Reversal of Charge-Induced Hydration Asymmetry.

The unique properties of water are critical for life. Water molecules have been reported to hydrate cations and anions asymmetrically in bulk water, being a key element in the balance of biochemical interactions. We show here that this behavior extends to charged lipid nanoscale interfaces.

Isolation and in vitro characterization of a novel immunosuppressive cyclosporine metabolite.

A novel metabolite (M-E) was identified by high-performance liquid chromatography in the serum of cyclosporine-treated renal transplant recipients during a second wave of immunosuppressive activity after disappearance of the initial wave due to the direct effect of CsA. M-E was identified in human serum and porcine bile both by HPLC and by a preparative thin-layer chromatography (TLC). It demonstrated homogeneity with characteristic retention times on C8 and C18 column HPLC systems using a variety of elution systems, and distinctive TLC mobility (Rf 0.

Thin-layer chromatographic detection of cyclosporine and its metabolites in whole blood using rhodamine B and alpha-cyclodextrin.

High-performance thin-layer chromatography (HPTLC) has advantages for the analysis of cyclosporine (CsA) and its metabolites in peripheral blood not shared by the radioimmunoassay (RIA) or high-performance liquid chromatography (HPLC) methods. While separation by HPTLC and HPLC is based on relative hydrophobicity, HPTLC (unlike HPLC) is capable of concurrent multisample analysis without expensive instrumentation. As distinguished from RIA, HPTLC detects CsA and metabolites as separate components, and does not use radioactive reagents.

Intramolecular general base-catalyzed ester hydrolyses by the imidazolyl group.

Intramolecular general base catalysis by the imidazolyl group was found in the hydrolyses of endo-5-[4;(5')-imidazolyl]-bicyclo[2.2.1]hept-endo-2-yl trans-cinnamate and endo-5-[4'(5')-imidazolyl]bicyclo[2.