Structural imprints in vivo decode RNA regulatory mechanisms.

Visualizing the physical basis for molecular behaviour inside living cells is a great challenge for biology. RNAs are central to biological regulation, and the ability of RNA to adopt specific structures intimately controls every step of the gene expression program. However, our understanding of physiological RNA structures is limited; current in vivo RNA structure profiles include only two of the four nucleotides that make up RNA.

Plasmonically active micron-sized beads for integrated solid-phase synthesis and label-free SERS analysis.

Self-assembly of gold nanospheres with a very thin glass shell onto the surface of beads yields a plasmonically active micron-sized substrate for integrated solid-phase synthesis and label-free SERS analysis. The proof-of-principle of this approach is demonstrated by the vibrational spectroscopic discrimination of three distinct amino acids and a dipeptide.

Nucleotide recognition in water by a guanidinium-based artificial tweezer receptor.

The water-soluble tweezer receptor 1 with two symmetric peptidic arms, which are connected by an aromatic scaffold and contain lysine, phenylalanine, and a guanidinium-based anion-binding site as headgroup, has been synthesized. UV/Vis-derived Job plots show that the receptor forms 1:1 complexes with nucleotides and phosphate in buffered water at neutral pH. Binding constants have been determined by fluorescence and UV/Vis spectroscopy.

Quantitative, label-free and site-specific monitoring of molecular recognition: a multivariate resonance Raman approach.

A site-specific and quantitative approach for label-free monitoring of molecular recognition is presented. Specifically, the binding site of an artificial receptor is probed selectively by UVRR spectroscopy. The ligand binding constant can be determined by non-negative matrix factorization.