VIEW HEADLINES ONLY

Bacterial Hydrogen Fuel Cell May Yield Cleaner World

Scientists at Penn State are working on a new, improved fuel cell.  Its secret?  Bacteria that can be coaxed with a little electricity to produce “four times as much hydrogen directly out of biomass than can be generated typically by fermentation alone.”  Will you someday be able to harness hydrogen from organic waste to drive […]

Molecular Motors Do Ballet

Scientists at University of Illinois studied dynein and kinesin – the tiny molecular trucks that ferry cargo inside the living cell – and found that they are not just individualists: they cooperate in a delicate yet effective performance.     Some scientists had thought that the two machine types, which travel in opposite directions, were […]

Flagellum Described in High-Performance Lingo

The bacterial flagellum, a virtual icon of the intelligent design movement, has been studied by many researchers, notably Howard Berg of Harvard, an expert on chemotaxis (the attraction of bacteria to chemical stimuli).  Berg was interviewed in Current Biology1 and talked like a race car mechanic when discussing this molecular machine, though he is not […]

Your Linemen at Work: DNA Search and Rescue Machine Imaged in Action

DNA is amazing enough, but its automatic error-correction utilities are enough to stagger the imagination.  There are dozens of repair mechanisms to shield our genetic code from damage; one of them was portrayed in Nature1 March 31 (see also analysis by Sheila David in the same issue2) in terms that should inspire awe.     […]

The Future of Biology: Reverse Engineering

Just as an engineer can model the feedback controls required in an autopilot system for an aircraft, the biologist can construct models of cellular networks to try to understand how they work.  “The hallmark of a good feedback control design is a resulting closed loop system that is stable and robust to modeling errors and […]

Bacterial Engineering On Par With Higher Life

Bacteria aren’t the simple life-forms microbiologists used to envision, writes Zemer Gitai in Cell.1 Recent advances have demonstrated that bacterial cells have an exquisitely organized and dynamic subcellular architecture.  Like their eukaryotic counterparts, bacteria employ a full complement of cytoskeletal proteins, localize proteins and DNA to specific subcellular addresses at specific times, and use intercellular […]

Clutch Enables Your Motors to Achieve 100% Efficiency

Those little ATP synthase motors (see 01/30/2005 entry) in your body and (in all living cells) made news again in Nature1 last week.  Scientists in Tokyo performed an ingenious set of experiments to measure the efficiency of the F1 synthesizing domain.  They attached a tiny magnet to the camshaft so that they could turn it […]

Survival of the Fittest – or the Luckiest?

Evolutionists assume that bacteria spread because they evolve resistance to antibiotics and become more fit to survive.  That’s apparently not true, says a story in EurekAlert about a study from Imperial College, London: the spread of bacteria appears to be due to chance alone.     Here are two quotes from the article by team […]

Molecular Machine Parts Stockpiled in Readiness for Assembly

A team from the European Molecular Biology Laboratory has done a “4D” time-and-materials study of molecular machines, analyzing the process of assembly, reports EurekAlert.  They found that the cell stockpiles some parts and holds them in storage, but adds the crucial elements just in time. The researchers discovered that in yeast, key components needed to […]

Your Motors Are Turbo-Charged

Think how fast 6000 rpm is.  It would redline on most cars.  Yet you have motors in your body that make that speed look like slow-mo.     The Japanese have taken great interest in the cellular machine ATP synthase since its rotary operation was discovered in 1996 (see 12/22/2003 entry).  Maybe it’s because they […]

Flagellar Oars Beat Like Galley Slaves In Synchronization

The Dec. 14 issue of Current Biology1 investigated another mystery in the operation of eukaryotic flagella: Flagella are microtubule-based structures that propel cells through the surrounding fluid.  The internal structure of a flagellum consists of nine parallel doublet microtubules arranged around a central pair of singlet microtubules (Figure 1).  Force for propulsion is provided by […]

Bacterial Flagellum Reveals New Structural Complexity

The bacterial flagellum, the unofficial mascot of the Intelligent Design movement, got more praise from the evolutionary journal Nature this week: Samatey et al.1 analyzed the hook region in detail and found that it is composed of 120 copies of a specialized protein that “reveals the intricate molecular interactions and a plausible switching mechanism for […]

News Nuggets

Here’s a collection of news items that deserve quick notice: Mars Rumbles:  Mars still has minor earthquakes, says Space.com, That’s without plate tectonics, “But scientists don’t know exactly how Mars is constructed.”  The Mars Exploration Rovers, meanwhile, awaking from a winter’s nap, are still gathering science data long past their expected lifetime.  Evidence for past […]

Genome of Diatom Reveals Unanticipated Complexity

“Let’s play 20 questions.”: “OK, I’m game.  Animal, vegetable or mineral?” “Yes.” “I give up.” The answer is: a diatom.  Some of the most abundant one-celled organisms in the sea, and essential for regulating the global carbon cycle, diatoms seem to be part animal, vegetable and mineral.  Scientists aren’t sure how to classify them.  They […]

Burnt Bridges, Brownian Ratchets, and Self-Propelled Motors Keep Skin Young Looking

Rock climbers and cavers are familiar with mechanical devices called ascenders that enable them to climb ropes safely and easily.  Ascenders slide up the rope in one direction, but latch onto it tightly when pulled the other direction.  Now imagine the ascender by itself, hanging on the rope, in a flurry of winds blowing in […]
All Posts by Date