University of Michigan scientists have discovered a molecular assistant they’ve dubbed ‘Spy’ that helps bacteria excel at producing proteins for medical and industrial purposes.  While the prime motivation is to work at proteins for medicine and industry, finding responses that improve production of desired traits is news – and it will provoke a search and might enable an improvement in bacteria working for fuel production.

Spy Molecule From the University of Michigan. Click image for more info.

Bacteria are dynamic creatures that are widely used to manufacture proteins used in medicine and industry as well as in research for fuel production. However, the creatures’ dynamism can enable losing the point of the job.

Examples include many proteins can fall apart and get cut up inside the bacteria before they can be harvested. Other proteins collapse into useless tangles instead of folding properly, as they must in order to function normally.  Not every individual bacteria necessarily performs optimally, some are just not working.  In medicine production where the scale is smaller than fuels and the costs and risks much higher, this can be a major concern.

James Bardwell, a professor of molecular, cellular and developmental biology and of biological chemistry, as well as a Howard Hughes Medical Institute investigator, at the University of Michigan is leading a research team that’s developed a way to coerce bacteria into making large quantities of stable, functional proteins. Then, in exploring why these designer bacteria were so successful, the scientists discovered the molecular helper, now named Spy.

Here is the UM story: The UM team inserted a particularly unstable protein into Escherichia coli (E. coli), which forced the bacteria to either adapt by improving protein stability or die when exposed to antibiotics. Through a ‘directed evolution’ experiment, in which the scientists selected colonies with increasing antibiotic resistance – and increasing protein stability – the team generated designer bacteria that produced up to 700 times more of the previously unstable protein.

The team’s paper published Feb.13, 2011 in the journal Nature Structural & Molecular Biology.

Postdoctoral fellow Shu Quan, who spearheaded the work, said, “It is exciting to realize that if even bacteria are asked in the right way, they can come up with good solutions to hard problems.”

To see why the designer bacteria were so much better at producing proteins, the scientists examined and found that the efficient microbes were making much more of the small protein called Spy. Further study showed that the cradle-shaped Spy aids in protein refolding and protects unstable proteins from being cut up or sticking to other proteins.

Bardwell looks ahead saying, “Our work may usher in an era of designer bacteria that have had their folding environment customized so that they can now efficiently fold normally unstable proteins.”

It’s fair to assume that making proteins isn’t the same as making oils or carbohydrates, but the process of ‘directed evolution’ might turn up something quite valuable in the fuel research arena.  Note the team posed a choice to the DNA response in the bacteria.  The survivors offered a massive improvement.  A 700 hundred-fold increase is a stunning reversal of fortune.

The question for bacteria in fuel production seems to be more products or die.  Now just how to set up to ask that is the question for researchers.  When someone does, it might become a huge productivity gain.


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