US researchers discovered a microorganism in greenhouse camel crickets that can break down lignin from wood. This breakthrough has the potential for finding microorganims that could degrade different kinds of waste pollutants.
Team leaders Stephanie Matthews and Rob Dunn from Campbell University and NC State University, respectively, emphasized "the need to reduce the production and accumulation of recalcitrant materials in the future," according to Physics World. Moreover, in addition to degrading industrially-produced compounds, there is an urgent need to break down those that pollute landfills and the environment.
The search for microbes to break down waste is an approach that could benefit the environment. "We knew that camel crickets can eat almost anything, so we began to wonder what bacteria might be present in a camel cricket's gut that allows them to do this," says Dunn.
Different microbes in camel crickets were identified and tested and Cedecea lapagei, a strain of bacteria, became the main interest. The findings showed that this bacteria can break down lignin.
According to Physics World, "Lignin (or lignocellulose) is the most abundant biopolymer on Earth and is very difficult to break down. It could be used as biofuel, however, if it could be degraded into its sugar molecules. This is no easy task since lignin contains several types of monomers and distorts when chemically processed. Paper factories, for example, often simply incinerate it and use it for fuel rather than try to convert it into commercial bioproducts."
The edge of C. lapegei is its capacity to survive in different environmental conditions
The research was based on a question set by citizens to the researchers on a 2014 citizen study that involves camel crickers. Citizens asked what could be the benefits of these organisms. "It was this question that led us to consider more specifically whether their gut microbes might be able to live in and degrade black liquor - a waste product from the paper pulp industry that consists mainly of lignin," explains Dunn.
The team sterilized the surface of camel crickets and hide beetles (as control) known as Dermestes maculatus, to exterminate bacteria on their exoskeletons and concentrate on the ones in their gut. The creatures were homogenized and bacteria were grown on different food substrates that include lignin independently and lignin in black liquor.
"We then identified the bacteria that grew, compared them to known bacteria and subsequently studied them in more detail," explains Dunn. "These studies included identifying some of the genes and enzymes of these bacteria that might be responsible for their unique abilities to grow on and degrade lignin."
"As well as identifying bacteria potentially able to turn pulp paper waste into energy, and hence get rid of a pollutant, we've identified a repeatable approach to finding new useful organisms that might break down other types of waste," Dunn tells Physics World. "This might include plastic or other products that cause major pollution problems."
