ScienceDaily (July 6, 2011) — One of the peskiest household pests, while disastrous to homes, could prove to be a boon for cars, according to a Purdue University study.
Mike Scharf, the O. Wayne Rollins/Orkin Chair in Molecular Physiology and Urban Entomology, said his laboratory has discovered a cocktail of enzymes from the guts of termites that may be better at getting around the barriers that inhibit fuel production from woody biomass. The Scharf Laboratory found that enzymes in termite guts are instrumental in the insects' ability to break down the wood they eat.
The findings, published in the early online version of the journal PLoS One, are the first to measure the sugar output from enzymes created by the termites themselves and the output from symbionts, small protozoa that live in termite guts and aid in digestion of woody material.
"For the most part, people have overlooked the host termite as a source of enzymes that could be used in the production of biofuels. For a long time it was thought that the symbionts were solely responsible for digestion," Scharf said. "Certainly the symbionts do a lot, but what we've shown is that the host produces enzymes that work in synergy with the enzymes produced by those symbionts. When you combine the functions of the host enzymes with the symbionts, it's like one plus one equals four."
Scharf and his research partners separated the termite guts, testing portions that did and did not contain symbionts on sawdust to measure the sugars created.
Once the enzymes were identified, Scharf and his team worked with Chesapeake Perl, a protein production company in Maryland, to create synthetic versions. The genes responsible for creating the enzymes were inserted into a virus and fed to caterpillars, which then produce large amounts of the enzymes. Tests showed that the synthetic versions of the host termite enzymes also were very effective at releasing sugar from the biomass.
They found that the three synthetic enzymes function on different parts of the biomass.
Two enzymes are responsible for the release of glucose and pentose, two different sugars. The other enzyme breaks down lignin, the rigid compound that makes up plant cell walls.
Lignin is one of the most significant barriers that blocks the access to sugars contained in biomass. Scharf said it's possible that the enzymes derived from termites and their symbionts, as well as synthetic versions, could be more effective at removing that lignin barrier.
Sugars from plant material are essential to creating biofuels. Those sugars are fermented to make products such as ethanol.
"We've found a cocktail of enzymes that create sugars from wood," Scharf said. "We were also able to see for the first time that the host and the symbionts can synergistically produce these sugars."
Next, Scharf said his laboratory and collaborators would work on identifying the symbiont enzymes that could be combined with termite enzymes to release the greatest amount of sugars from woody material. Combining those enzymes would increase the amount of biofuel that should be available from biomass.
The U.S. Department of Energy and Chesapeake Perl funded the research.
Source : ScienceDaily
Showing posts with label Termite. Show all posts
Showing posts with label Termite. Show all posts
Tuesday, July 26, 2011
UF review suggests new approaches needed if biological control of termites to succeed
GAINESVILLE, Fla. — It sounds like a pest control technician’s dream come true — eradicating hard-to-reach underground termite colonies by introducing small quantities of a pathogen or parasite, a practice called biological control.
But after 50 years of research, scientists have yet to deliver a successful method. Researchers’ efforts have been hindered by flawed experiments and lack of field testing, according to experts with the University of Florida’s Institute of Food and Agricultural Sciences.
Their findings appear in a review article published online this week by the journal Biological Control.
Subterranean termites account for 80 percent of the nation’s annual $4.1 billion in termite control expenses. Colonies can hold anywhere from 100,000 to 1 million of the wood-destroying insects, and miles of pencil-sized tunnels.
In past studies conducted at many institutions, researchers have experimented with fungi, bacteria, nematodes and viruses thought to be promising biological control agents, said Thomas Chouvenc, a postdoctoral associate with UF’s Fort Lauderdale Research and Education Center and the review’s lead author. In a typical study, termites in a confined space are exposed to an enemy organism, often at concentrations impossible to achieve in the wild.
“We can kill a bug in a jar, but the vast majority of these studies don’t describe any way to implement that approach in the real world,” Chouvenc said.
Distributing a pathogen or parasite in a termite colony is no easy task, said Nan-Yao Su, a UF entomology professor at the center and another author of the study. He developed a baiting system widely used to control subterranean termites.
The insects detect and avoid some fungal pathogens, and will close tunnels to confine threats. Other behaviors, such as constant grooming and removal of dead individuals, reduce the likelihood of pathogen transmission.
Among the 227 studies analyzed, many were authored by scientists who were not termite experts and probably had little understanding of the insects’ behavior, Su said.
Biological control of subterranean termites may be possible, he said, but researchers should learn from past mistakes — notably, the focus on soil-dwelling fungi as potential control agents.
“Termites have lived in the soil with those fungi for millions of years, and they have evolved a wide range of mechanisms to prevent the pathogens from spreading within the colony,” Su said. “You need something that has not co-evolved with termites.”
The key to success, Chouvenc said, might be finding a pathogen that can spread to other termites before its host dies, not after.
Both researchers say journals are often biased toward publishing studies that show positive results, meaning that scientists may not learn about unsuccessful experiments.
“We need to encourage negative reporting so we don’t replicate the same mistakes,” Su said.
Source : http://news.ufl.edu/2011/07/20/termite-biocontrol/
But after 50 years of research, scientists have yet to deliver a successful method. Researchers’ efforts have been hindered by flawed experiments and lack of field testing, according to experts with the University of Florida’s Institute of Food and Agricultural Sciences.
Their findings appear in a review article published online this week by the journal Biological Control.
Subterranean termites account for 80 percent of the nation’s annual $4.1 billion in termite control expenses. Colonies can hold anywhere from 100,000 to 1 million of the wood-destroying insects, and miles of pencil-sized tunnels.
In past studies conducted at many institutions, researchers have experimented with fungi, bacteria, nematodes and viruses thought to be promising biological control agents, said Thomas Chouvenc, a postdoctoral associate with UF’s Fort Lauderdale Research and Education Center and the review’s lead author. In a typical study, termites in a confined space are exposed to an enemy organism, often at concentrations impossible to achieve in the wild.
“We can kill a bug in a jar, but the vast majority of these studies don’t describe any way to implement that approach in the real world,” Chouvenc said.
Distributing a pathogen or parasite in a termite colony is no easy task, said Nan-Yao Su, a UF entomology professor at the center and another author of the study. He developed a baiting system widely used to control subterranean termites.
The insects detect and avoid some fungal pathogens, and will close tunnels to confine threats. Other behaviors, such as constant grooming and removal of dead individuals, reduce the likelihood of pathogen transmission.
Among the 227 studies analyzed, many were authored by scientists who were not termite experts and probably had little understanding of the insects’ behavior, Su said.
Biological control of subterranean termites may be possible, he said, but researchers should learn from past mistakes — notably, the focus on soil-dwelling fungi as potential control agents.
“Termites have lived in the soil with those fungi for millions of years, and they have evolved a wide range of mechanisms to prevent the pathogens from spreading within the colony,” Su said. “You need something that has not co-evolved with termites.”
The key to success, Chouvenc said, might be finding a pathogen that can spread to other termites before its host dies, not after.
Both researchers say journals are often biased toward publishing studies that show positive results, meaning that scientists may not learn about unsuccessful experiments.
“We need to encourage negative reporting so we don’t replicate the same mistakes,” Su said.
Source : http://news.ufl.edu/2011/07/20/termite-biocontrol/
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