Navigation Links
McBride shows DNA detective work with paper-eating bacteria that 'glide'

The eco-friendly fuel ethanol is usually made from grain, but the U.S. Department of Energy (DOE) would like to find other renewable materials that will be cost-effective alternatives, such as paper pulp, sawdust, straw and grain hulls.

A UWM professor recently helped DOE do just that by analyzing the DNA of a bacterium that can break down cellulose, the major structural component of plants that is also found in forestry by-products (including paper) and waste feedstocks.

Mark McBride, a professor of biological sciences, worked with DOE's Joint Genome Institute and scientists at Los Alamos National Laboratory to examine the genes of Cytophaga hutchinsonii that are responsible for the organism's ability to digest cellulose ?the first step in the carbohydrate's conversion into ethanol.

Sequencing the genome of C. hutchinsonii provides what McBride calls a "parts list" for the microbe, allowing scientists to explore how bacteria use these parts to build and run their key functions ?some of which have potential uses in bioenergy.

The genome has revealed surprises, he says.

"Microorganisms typically require two kinds of enzymes to efficiently break down cellulose," he says. "One type cuts the long carbohydrate molecule through the middle, while another chews small pieces from the ends."

Not so with C. hutchinsonii. Although it efficiently digests cellulose, in DNA analysis it appears to be lacking one of the usual enzymes, suggesting that it may use either a novel strategy or novel enzymes.

The information McBride reports could help DOE devise mixtures of microorganisms or enzymes that will more efficiently convert cellulose into glucose, and finally into ethanol.

McBride's interest in C. hutchinsonii goes beyond its possible value in bioenergy.

What really intrigues him is that it's a "gliding bacterium," able to crawl rapidly over surfaces by an unknown mechanism, which is the main subject of McBride's research with another glider called Flavobacterium johnsoniae. The two microbes are not closely related.

"You are more closely related to a fruit fly than these two organisms are to each other," he says.

However, from analysis of genes from the two bacteria, McBride suspects that they use the same basic machinery to move.

And there may be another connection. F. johnsoniae doesn't eat cellulose, but it is able to digest a similar carbohydrate polymer, chitin. Like cellulose, chitin, which is found in the hard shells of lobsters and insects, is also difficult to break down.

McBride hypothesizes that digestion of cellulose and chitin may also be linked to cell movement, or motility.

"Loss of motility results in loss of ability to digest chitin," he says. "This suggests that motility and digestion of some carbohydrate polymers may be connected in both gliding microbes."

McBride and his students have used F. johnsoniae to study the motility of gliding bacteria for more than a decade. They cloned "mutants" of F. johnsoniae that are unable to move, and then attempted to "repair" them by inserting certain pieces of DNA.

In this way, they have uncovered nearly all the genetic components that propel the cells. It has been a long process. A decade ago, his lab had found one protein involved. He now knows of 24, and he doesn't expect to find many more.

Until recently, McBride was not able to image the bacteria closely enough to see the structures involved in movement. Instead, he bonded latex spheres to the surface of F. johnsoniae cells and observed that they moved in all directions around the cell's perimeter.

"The cell wall appears to have a series of moving conveyer belts," he says.

He also has learned that some of the motility proteins ("parts") act at the surface of the cell, and he thinks some are involved in forming nearly invisible filaments around the perimeter of t he cell.

These filaments were recently imaged in collaboration with Sriram Subramaniam and Jun Liu at the National Institutes of Health by cryo-electron tomography.

"The filaments may be the cell's 'tires,' and there are different kinds," McBride says. "They are designed to help the organism move over a variety of surfaces, like an all-terrain vehicle."

Besides providing movement, McBride says the filaments also may be needed to move the cellulose and chitin molecules to certain sites where they can be digested or taken into the cell.

McBride hopes the complete genome for C. hutchinsonii will yield other clues to the interconnections among gliding bacteria. He is now collaborating with DOE to sequence the entire genome of F. johnsoniae, which will allow a full comparison of the genes of the two microorganisms.


'"/>

Source:University of Wisconsin - Milwaukee


Related biology news :

1. Genome of deadly amoeba shows surprising complexity, evidence of lateral gene transfer
2. “Nano-scissors?laser shows precise surgical capability
3. Clam embryo study shows pollutant mixture adversely affects nerve cell development
4. New imaging method gives early indication if brain cancer therapy is effective, U-M study shows
5. Study shows nanoshells ideal as chemical nanosensors
6. Gene vaccine for Alzheimers disease shows promising results
7. Flocking together: Study shows how animal groups find their way
8. New drug shows promise as powerful anticancer agent
9. Loves all in the brain: fMRI study shows strong, lateralized reward, not sex, drive
10. Test for early detection of prostate cancer shows promise
11. Mouse gene shows new mechanism behind cardiac infarction in man
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:3/20/2017)... 2017 PMD Healthcare announces the release of ... Management System (WMS), a remote, real-time lung health monitoring ... Healthcare is a Medical Device, Digital Health, and Chronic ... creating innovative solutions that empower people to improve their ... PMD developed the first ever personal spirometer, Spiro PD, ...
(Date:3/9/2017)... SAN FRANCISCO and MOUNTAIN VIEW, ... Zipongo , "Eating Well Made Simple," and 23andMe ... to help guide better food choices.  Zipongo can now ... only their food preferences, health goals and biometrics, but ... to certain food choices. Zipongo,s personalized food ...
(Date:3/2/2017)... -- Summary This report provides all the information ... and activities since 2010. ... Read the full report: http://www.reportlinker.com/p03605615-summary/view-report.html ... provides an in-depth insight into the partnering activity of one ... demand company reports are prepared upon purchase to ensure inclusion ...
Breaking Biology News(10 mins):
(Date:3/23/2017)...  Agriculture technology company Cool Planet has closed on ... to commercialize its Cool Terra and Cool Fauna Engineered ... that are simultaneously profitable as well as sustainable and ... months. This latest round of funding was led by ... The company,s primary product, Cool Terra, can improve ...
(Date:3/22/2017)... Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN), today announced a ... Biobank and GSK to generate genetic sequence data from the ... will enable researchers to gain valuable insights to support advances ... of serious and life threatening diseases. ... Genetic evidence has revolutionized ...
(Date:3/22/2017)... Calif. , March 22, 2017  UBM ... proud to announce their extended partnership and the ... be headlined by the 21 st Annual ... Boston, taking place May 3-4, 2017. ... Medical Technology Association (ADVAMED) President and CEO, ...
(Date:3/22/2017)... Mass. , March 22, 2017   iSpecimen ... today announced that Doctors Pathology Service (DPS), ... region of the United States , ... Delaware Health Information Network (DHIN) to make ... The novel program, announced in 2015 ...
Breaking Biology Technology: