Deciphering Complexity in Molecular Biophysics with Single-Molecule Resolution

Towards physiological complexity with in vitro single-molecule biophysics.

Single-molecule biology has matured in recent years, driven to greater sophistication by the development of increasingly advanced experimental techniques. A progressive appreciation for its unique strengths is attracting research that spans an exceptionally broad swath of physiological phenomena--from the function of nucleosomes to protein diffusion in the cell membrane. Newfound enthusiasm not...

Single-molecule biophysics: untying a nanoscale knot.

Single Molecule DNA Biophysics with Atomic Force Microscopy

Structural and functional properties of double stranded deoxyribonucleic acid (dsDNA) are investigated by atomic force microscopy (AFM) on a single molecule level. Here, we characterize different linear and circular DNA systems in terms of their geometry and topology, and visualize enzyme binding of restriction endonuclease Hae III to DNA. Manipulation of single DNA molecules is demonstrated by...

Single-molecule high-resolution imaging with photobleaching.

Conventional light microscopy is limited in its resolving power by the Rayleigh limit to length scales on the order of 200 nm. On the other hand, spectroscopic techniques such as fluorescence resonance energy transfer cannot be used to measure distances >10 nm, leaving a "gap" in the ability of optical techniques to measure distances on the 10- to 100-nm scale. We have previously demonstrated t...

Optical traps for single molecule biophysics: a primer

Optical trapping experiments of different complexities are making a significant impact in biology. This review seeks to highlight design choices for scientists entering the field or building new instruments and to discuss making calibrated measurements with optical traps. For specificity, this review focuses on nucleic acid-based assays, but the discussion reflects the general experimental desi...