In a review to be published in Biofuels, Bioproducts & Biorefining, Scharf and his colleague Aurélien Tartar describe how the enzymes produced by both termites and the micro-organisms that inhabit their gut – known as symbionts – could help to produce ethanol from non-edible plant material such as straw and wood.
“Through millions and millions of years of evolution, termites and their symbionts have acquired highly specialised enzymes that work together to efficiently convert wood and other plant materials into simple sugars,” says Scharf. “These enzymes are of the most value to bioethanol production.”
Current bioethanol production processes tend to use edible plant materials, such as starch from corn (maize) and sugar from sugar cane, which contain easily accessible sugar molecules that can be fermented to produce ethanol. However, using food crops to produce ethanol has proved highly controversial, with bioethanol being blamed for much of the recent rises in food prices.
The non-edible parts of many plants also contain a large number of sugar molecules, which could potentially be used to produce ethanol. But the problem is that these sugar molecules are far less accessible. This is because they’re locked up within a substance known as lignocellulose, which provides structural support for plant cell walls.
Breaking this substance up into its component sugar molecules is far from easy. One approach involves pretreating the lignocellulose by heating it in combination with acids or bases and then exposing the pretreated material to various enzymes. Another approach is very fine grinding followed by enzymatic treatment.
Termites, on the other hand, don’t seem to have too much trouble digesting wood and other lignocellulosic materials into their component sugars, as many homeowners can attest. The termite appears to favour the fine grinding approach in combination with its own unique set of enzymes. These enzymes are secreted by both termites and the symbionts that colonise their gut, and act on the lignocellulose that has been chewed to very small particle sizes by the termite.
Despite the small size of the termite gut and the difficulty in analysing its contents, a few research groups have attempted to study what Scharf and Tartar call the termite digestome. This is the pool of genes, both termite and symbiont, that code for the enzymes that break down and digest lignocellulosic material.
Using a variety of genomic and proteomic techniques, these groups have managed to identify a number of the main enzymes, many of which could prove useful for producing ethanol. This work has already provided strong preliminary evidence that the enzymes produced by the termites and their symbionts tend to work collaboratively, with the lignocellulosic material having to be partially digested by termite enzymes before it can be further digested by symbiont enzymes.
But the study of the termite digestome has really only just begun. “There are many directions that the science can now head,” says Scharf. “First, we now have the ability to produce and test individual enzymes for their competency and roles in lignocellulose degradation. Once we identify major players (from termites and symbionts), we can test combinations that may have applications in making bioethanol production more feasible from existing feedstocks, and maybe even other feedstocks that aren't on our radar screens yet.”
This kind of digestome analysis could also be applied to other insects that feed on woody material, such as wood-boring beetles, and certain wasps and flies, Scharf adds.
Six-legged livestock -- sustainable food production
11.05.2017 | Faculty of Science - University of Copenhagen
Elephant Herpes: Super-Shedders Endanger Young Animals
04.05.2017 | Universität Zürich
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy