A Plethora, Nay, Dare I Say, A Veritable Cornucopia

Holy jeebus, I finally got around to looking at what Pubmed sent me for "What's new for 'Single Molecule'" last week, and there is too much there to even begin to consider reading.  Rather than try to read all of this and summarize, I just want to point out what look like some highlights based on the abstracts.  When I get a chance to read some of this later on, I'll try to fill in the details:

Force spectroscopy

• Theory, analysis, and interpretation of single-molecule force spectroscopy experiments: Olga Dudko's group updates their highly important theoretical work on interpreting non-equilibrium single molecule folding and unfolding experiments with this new paper.  From people who read the pre-print, I understand the functions they give in this paper give much more robust fits than the ones in their previous work.
  
• Length of Time's Arrow: Gavin Crooks (of the Crooks Fluctuation Theorem fame) has a paper in Phys Rev Lett which uses the reversible folding and unfolding of RNA molecules to investigate fundamental questions of why time runs in one direction.  That is some seriously hardcore physics, and one of the rare few examples of "biology in the service of physics" rather than "physics in the service of biology."  I hope I haven't forgotten too much stat mech to make heads or tails of this, but I'm going to give it my best.
• Remeasuring the Double Helix: While not strictly about force spectroscopy (nor actually single molecule, for that matter), this paper from a group here at Stanford uses small angle X-ray scattering (SAXS) to investigate the bending behavior of small DNA molecules, a very hot topic.  This relates to single molecule force spectroscopy because some experiments show the apparent behavior of short molecules differing markedly from the behavior seen in single molecule pulling experiments of longer molecules.  This work supports the view of Jon Widom's work (among others) showing much higher flexibility than expected for short double stranded DNAs.

Fluorescence

• Single-molecule spectroscopy of fluorescent proteins: Vijay Vinod Subramaniam is an expert on photophysics of fluorescent protein, and as these proteins are getting used more and more for single molecule assays, their photophysics in the single molecule regime are more important.  This looks interesting.
• A stochastic single-molecule event triggers phenotype switching of a bacterial cell: I haven't been following Sunney Xie's work very closely, but they have been working on single molecule detection of gene regulation, and this new work continues along that direction.  Probably worth a look-see.
  

UPDATE: A reader corrected me on Vinod Subramaniam's first name; I was thinking of the late great Vijay Pandharipande, from whom I took QM in grad school.

Article Title of the Day

Tentacle probe sandwich assay in porous polymer monolith improves specificity, sensitivity and kinetics.

Mmm...tentacle probe sandwich...

Friday Cat Blogging!

Just because I can.

New advances in single molecule NMR

A while back, I blogged about some experiments back in 2004 demonstrating detection of single spins.  Now, two back to back* papers in Nature have utilized a new method for detecting single spins at room temperature.  Nature also has a News and Views that discusses both papers.  Both techniques utilize long spin coherence states of diamond nanocrystals with single defects, which sense changes in spin tens to hundreds of nanometers away, and can be detected optically.  Optical detection is a highly desirable mechanism because of the highly developed technologies allowing reliable, low-noise detection of single photons.  And, the ability to image spins at room temperature offers hope that these techniques could be used for biological studies.

*Belly to belly!

A Nobel Prize for Acronyms

Roger Tsien won the Nobel prize in Chemistry today for his work on GFP, a resounding affirmation of the role that goofy acronyms play in biophysics.  The Tsien lab gave us such memorable names as "Fluorescein arsenical helix binder" (FlAsH), "resorufin arsencial helix binder" (ReAsH), and its brominated cousin (BrAsH).  I seem to recall being told, back when my advisor was doing a sabbatical in their lab, that they were working on a fluorescein-based histidine binding dye which they were calling "hissy fit", but I can't seem to find any evidence of that in the literature.  In any case, congratulations, and here's to a future filled with puns!

From the Cold to the Old

Via the CM/AMO rumor mill, Phillipe Cluzel  has moved from U Chicago to Harvard.  The Cluzel lab has done work on in vivo mRNA quantification (a hot topic in a lot of labs), as well as trying to understand the dynamics of the network that controls bacterial chemotaxis.  I interviewed for a postdoc with the Cluzel lab before winding up here at Stanford, and I have to say I'm pretty glad that I wind up working there so that I could arrive just prior to a lab move; there's no better way to lose six months of research time than to have totear down a lab, move it 1000 miles, and set it up in a new place.  That aside however, congrats to the Cluzel lab, and good luck at Harvard (or as Tommy Angelini, a friend and postdoc there likes to call it, "Tardvard.")