HAPPY TRAILS

SHSU scientists say environmentally friendly microbes may help restore worn wilderness pathways

Instead of always being destructive, as is often thought, they may instead become useful in such practical work as restoring damaged wilderness hiking trails or in solving such theoretical questions as whether life ever existed on Mars.

The researchers are Harry Kurtz Jr., assistant professor in the Department of Biological Sciences, and Dennis Netoff, associate professor in the Department of Geography and Geology. Kurtz was scheduled to present their findings at the 98th General Meeting of the American Society for Microbiology Wednesday morning in Atlanta.

Kurtz titled his presentation "Microbial Glue and Cosmic Questions." The paper resulted from research funded by grants from the Faculty Research Council of Sam Houston State University and from the Glen Canyon Natural History Association, with additional funds from their departments.

"Geologists and microbiologists have traditionally viewed microbes as destructive agents in geological processes," said Kurtz. "However, this view may not always be accurate.

"Our investigations of microbial communities on sandstone outcrops in the Colorado Plateau (southeastern Utah) show that the organisms residing in and on the stone surfaces act to protect the otherwise friable rock from the effects of wind and rain."

That erosive process is often started by people hiking and biking in remote areas, causing such agencies as the National Park Service to restrict access, and leading to their seeking ways to stabilize areas that have been damaged or could be damaged by future use. Kurtz and Netoff belive that microbes may have the potential to do this.

The two researchers reached their conclusions after a series of experiments designed to understand the role of these microbial communities in their natural environment. They first had to establish a set of complex cultures from the samples under study.

By inoculating a mineral solution containing bicarbonate as the sole carbon source and providing illumination, they were able to generate the complex cultures. Following this, they were able to regenerate the microbial community by the addition of a small sample of culture to crushed sandstone.

"After extended incubation, growth of the bacterial communities became apparent due to the green coloration of the sand where the microbes were applied," said Kurtz. "Matured cultures were allowed to dry to completion and examined for consolidation of the loose sand. We found that the presence of bacterial growth significantly hardened the sand surface."

The secret to the microbes' success in doing this could be as simple as the starchy, pasty glue sometimes used in grammar school art projects. When provided water and needed nutrients, the microbes produce acidic polysaccharides--starches which have the potential to bind metal ions.

Kurtz and Netoff believe that providing microbes already present in damaged or threatened areas with a water-based spray which includes needed nutrients could encourage bacterial colonization and hardening of surfaces.

The researchers also believe that by understanding more about how microbes work, their studies may aid the nation's quest to determine if life ever existed on Mars and in which areas of the planet such traces are most likely to be found.

Scientists are now studying a Martian meteorite found in Antarctica, which some believe may have evidence of life pre-existing on Mars. Netoff is intrigued by what he has seen from Pathfinder fly-by data, and is trying to compare it with what he and Kurtz have found in the Utah wilderness. But they don't expect conclusions until Mars material is analyzed there or returned here for analysis.

"We're not going to be able to prove whether life existed there or not until we have uncontaminated samples from there," said Kurtz. "Until then maybe we can fix some trails and learn some more about these misunderstood microbes."

Media Contact: Frank Krystyniak
May 20, 1998
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