Robert C Lewis

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Single-pair fluorescence resonance energy transfer was used to track RNA exiting from RNA polymerase II (Pol II) in elongation complexes. Measuring the distance between the RNA 5' end and three known locations within the elongation complex allows us determine its position by means of triangulation. RNA leaves the polymerase active center cleft via the(More)
Remodelling protein nucleic acid interfaces is an important biological task, which is often carried out by nucleic acid stimulated ATPases of the Swi2/Snf2 superfamily. Here we study the mechano-chemical cycle of such an ATPase, namely the catalytic domain of the Sulfolobus solfataricus Rad54 homologue (SsoRad54cd), by means of fluorescence resonance energy(More)
Crystallographic studies of the RNA polymerase II (Pol II) elongation complex (EC) revealed the locations of downstream DNA and the DNA-RNA hybrid, but not the course of the nontemplate DNA strand in the transcription bubble and the upstream DNA duplex. Here we used single-molecule Fluorescence Resonance Energy Transfer (smFRET) experiments to locate(More)
The photophysical properties of three new water-soluble terrylenediimide (WS-TDI) derivatives are investigated and their utilization in biological experiments is demonstrated. Each of these dyes can be excited in the far red region of the visible spectrum, making them good candidates for in-vivo studies. Single-molecule techniques characterize their(More)
Microelectrodes, made from a Cl(-)-selective liquid ion exchanger previously used to measure putative Cl- fluxes in Lilium longiflorum pollen tubes, were characterized. The electrodes were poorly selective, possessing only about 10-fold selectivity for Cl- over other anions tested. They had only 2.4-fold selectivity for Cl- over the anionic form of the H+(More)
A miniature kinematic mount allows adjustment of mirror pointing inside ultrahigh vacuum (UHV) by rotating finely threaded screws outside of vacuum. The mount assembly is less than 0.620 in. in diameter, so it fits through the standard tubing used with miniature conflat flanges. The mount is a point-iine-plane device with a sapphire ball at the point(More)
The harmonic response and modal shapes of axially-symmetrical piezoceramic cylinders (tubes) polarised through the wall thickness have been predicted by finite element methods and determined experimentally. Analysis of ceramic cylinders has concentrated on the effects of the variation of diameter to thickness (d/t) ratios, and change in cylinder length (l).(More)
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