The influence of metal-complexing macrocycle size on intramolecular movement in rotaxanes.

[2]rotaxanes composed of a dibenzo-24-crown-8 wheel (DB24C8) and an axle containing two metal-complexing tetraazamacrocyclic units linked with a p-xylylene bridge, coordinating the same or different metal ions (Ni and/or Cu) are described. A symmetric di-Ni rotaxane crystallizes in the monoclinic P21/c space group with one rotaxane cation and four PF6- counterions in the asymmetric part of the unit cell. In the crystal, the cations and anions of the investigated compound form an intertwined 3D-framework with C-HF and C-Hπ intermolecular interactions.

Temperature dependent FCS studies using a long working distance objective: Viscosities of supercooled liquids and particle size.

In this work, we describe new experimental setups for Fluorescence Correlation Spectroscopy (FCS) where a long working distance objective is used. Using these setups, FCS measurements in a broad temperature range for a small sample volume of about 50 μl can be performed. The use of specially designed cells and a dry long working distance objective was essential for avoiding temperature gradients in the sample.

Comparison of the localization and post-translational modification of Campylobacter coli CjaC and its homolog from Campylobacter jejuni, Cj0734c/HisJ.

Campylobacter is an asaccharolytic microorganism which uses amino acids as a source of carbon and energy. CjaC/HisJ is a ligand-binding protein, a component of the ABC transport system. Campylobacter CjaC/HisJ is post-translationally modified by glycosylation.