Glowing Bacteria Could Help Pinpoint Pathogens, Cancer Cells
A team of Tech researchers led by Associate Professor of Chemistry Haiying Liu has discovered how to make E. coli glow under fluorescent light. The technique could eventually be used to track down pathogens and even help pinpoint cancer.
E. coli bacteria are naturally found in intestines and are usually harmless. But virulent strains can cause serious illness and even death.
Liu's team attached molecules of the sugar mannose to specially engineered fluorescent polymers and stirred them into water swimming with E. coli. Microscopic hairs on the bacteria hooked like Velcro onto the mannose molecules, effectively coating the bacteria with the polymers. When the researchers shined fluorescent light into the solution, the bacteria lit up under a microscope like blue fireflies.
The technique could be used to identify multiple pathogens by mixing and matching from a library of sugars and polymers that glow different colors. If blue means E. coli, fuchsia could one day mean influenza.
Liu is adapting the technique to combat breast cancer. Instead of mannose, he plans to link the fluorescent polymers to a peptide that homes in on cancer cells.
Once introduced to the vascular system, the polymers would travel through the body and stick to tumor cells. Then, illuminated by a type of near-infrared light that shines through human tissue, the polymers would glow, pinpointing the location of the malignant cells.
From the Roots Up, Growing Trees for Sustainable Biofuel
New tree varieties with wonder roots could one day supercharge the biofuel industry.
Victor Busov and his team aim to develop poplar trees that thrive in dry, infertile soils. Their work is funded by a three-year, $900,000 grant from the joint USDA and Department of Energy's Plant Feedstock Genomics for Bioenergy Research Program.
"Biofuel crops will be grown on marginal lands," says Busov, an associate professor in the School of Forest Resources and Environmental Science. "These plants will have to be pretty robust, and we're focusing on the roots."
The project has two parts. In the first, poplars will be grown in dry, nitrogen-poor soil, and researchers will track how the trees' genome responds. Then they will modify key genetic "hubs" to grow trees with roots suited to those conditions.
In the second experiment, they will generate random mutations in poplars.
If any of the plants thrive in dry, infertile conditions, the scientists will use that information to grow hardier varieties.
Developing trees that like poor, droughty soils could boost biofuel production and reduce dependence on petroleum. Plus, it could bring the biofuel industry closer to sustainability.
"If we start on the wrong foot, we are setting ourselves up for disaster in the long run," says Busov. "Using nitrogen and water more efficiently to produce biomass is simply more sustainable."
Michigan Tech Scientist Wins Google Earth Competition
Tyler Erickson, a research scientist at the Michigan Tech Research Institute in Ann Arbor, has created a new way to use Google Earth that lets anyone from a schoolkid to a scientist learn more about the comings and goings of carbon dioxide over North America. His efforts were compelling enough to win a Google Earth contest on presenting scientific results using KML. Programs like Google Earth can display a KML file through time, making an animation.
Most people think of Google Earth as a fun way to zoom around the planet without leaving the comfort of their computer. Tyler Erickson's KML file loads data on atmospheric carbon into Google Earth, so users can watch where carbon dioxide comes from and where it goes over time.
Named "North American Carbon," it relies on data collected by NASA-funded researcher Anna Michalak and her group at the University of Michigan. Erickson's project can help teachers, students, and the general public understand how atmospheric carbon dioxide is measured and how those measurements are affected by factors such as wind and weather.
To see Erickson's program, go to earth.google.com/gallery. In the search field at the top of the page, type "North American Carbon." You will need to download Google Earth software.
Pennington Named Jefferson Science Fellow
Wayne Pennington, professor and chair of the Department of Geological and Mining Engineering and Sciences, has been named a Jefferson Science Fellow by the US Department of State. Pennington is serving a one-year assignment working full-time as a senior engineering advisor with a group at the United States Agency for International Development.
He will help countries develop strategies to rebuild their infrastructure, particularly in post-disaster and post-conflict settings in Pakistan and Afghanistan. He will focus primarily on better energy development and distribution and on earthquake hazard mitigation.
"I can no longer complain about the apparent lack of knowledge of the oil and gas industry, or of the minerals industry, as our government assists post-disaster or post-conflict countries," Pennington says. "I look forward to bringing my knowledge and background—and frequently calling my contacts, as needed—to good use, particularly in the rebuilding and capacity-building efforts under way in Pakistan and Afghanistan. The people I work with are very smart, but the need to balance competing agendas among different constituents is always present, and the voice of science and engineering needs to be heard clearly."
Jet Fuel from Cabbage's Cousin Could Slash CO2 Emissions
The seeds of a lowly weed could cut jet fuel's cradle-to-grave carbon emissions by 75 percent. David Shonnard, Robbins Chair Professor of Chemical Engineering, measured the carbon dioxide emissions associated with jet fuel made from camelina oil over its entire life cycle, from planting to exhaust. "Camelina jet fuel is almost an exact replacement for fossil fuel, and it exhibits one of the largest greenhouse gas emission reductions of any agricultural feedstock-derived biofuel I've ever seen," he said. "This is the result of the unique attributes of the crop—its low fertilizer requirements, high oil yield, and the availability of its coproducts, such as meal and biomass, for other uses."
Camelina sativa originated in Europe and is a member of the mustard family, along with cabbage and canola. Sometimes called false flax, it thrives in the Northern Plains.
Camelina needs relatively little water or nitrogen fertilizer, and it can be grown on marginal agricultural lands. And unlike ethanol made from corn or soy-based biodiesel, it would not compete with food crops.
Shonnard conducted the life cycle analysis in collaboration with UOP LLC, of Des Plaines, Illinois, a subsidiary of Honeywell, and Targeted Growth Inc. of Seattle.
Exercise for Everyone
Do obese people avoid exercise because the equipment is not designed for them? Does the pain or discomfort sometimes associated with exercise keep them from working out?
Karen Roemer, an assistant professor in the Department of Exercise Science, Health and Physical Education, is looking at how exercise equipment might be hindering workouts of the seriously overweight. Specifically, Roemer records the movements of people of all shapes and sizes as they work out on a rowing machine.
To track movements, Roemer and her team use small, reflective markers attached to the rower's skin and photograph them with multiple cameras. Similar to modeling a golfer's swing for a videogame, the many markers are translated via software that reproduces the movement.
"These are complex biomechanical problems," Roemer says. To model the knee alone, they used MRI scans and collected motion analysis data using eighty reflective markers and twelve digital cameras.
The resulting model looks like it came from The Matrix: complicated processes and images broken down by all the markers, then reassembled to resemble the real knee.
"Potentially, we could give equipment manufacturers suggestions for new designs," says Roemer.