Jeeyeon Lee | PubMed Health

PubMed2004

NMR structural analysis of a modular threading tetraintercalator bound to DNA.

The synthesis and NMR structural studies are reported for a modular threading tetraintercalator bound to DNA. The tetraintercalator design is based on 1,4,5,8-tetracarboxylic naphthalene diimide units connected through flexible peptide linkers. Aided by an overall C(2) symmetry, NMR analysis verified a threading polyintercalation mode of binding, with linkers alternating in the order minor groove, major groove, minor groove, analogous to how a snake might climb a ladder. This study represents the first NMR analysis of a threading tetraintercalator and, as such, structurally characterizes a new topology for molecules that bind to relatively long DNA sequences with extensive access to both DNA grooves.

Binding Sites↗

PubMed2003

New method for analyzing the nitrite level in PC12 cells using capillary electrophoresis.

Nitric oxide (NO) is a gaseous molecule shown to have signal transmitter properties in organisms. Direct measurement of NO in physiological conditions has been difficult due to its short lifetime and low concentration. Nitrite has been used as a marker for NO formation in biological systems. Capillary electrophoresis (CE) has been recently used to measure nitrite in biological fluids. The purpose of this study is to analyze nitrite in PC12 cells (pheochromocytoma cell line) using CE. Optimal CE performance was employed with 150 mM Tris-phosphate, 6 microM hexadecyltrimethyammonium chloride buffer at pH 7.0 and a fused-silica column of 57 cm x 75 microm I.D. The signal was measured with a UV detector at 214-nm wavelength and negative potential of 10 kV was applied for nitrite analysis. Under the optimum conditions, we monitored the changes in the concentration of the nitrite levels through synergistic stimulation of tumor necrosis factor alpha plus gamma-interferon in PC12 cells.

Animals↗