The results, published online on the Nature biotechnology (1) website, show that only a few genes are responsible for the fungus's enzymatic activity. They offer new avenues for the fabrication of second generation biofuels from plant waste.
The fungus Trichoderma reesei was discovered in the South Pacific during the Second World War, where it was damaging American military equipment and was defeating every attempt at protecting the equipment with cotton cloth. The fungus contains a number of enzymes, cellulases, with potent catalytic properties that break down plants. It is considered to be the world's most efficient fungus at breaking down the cellulose in plant walls into simple sugars, which it feeds on.
After fermentation, simple sugars can easily be transformed into biofuels such as ethanol. First generation agrofuels, made from grain or from beet, have certain limitations. Second generation biofuels, made from foresting and agricultural waste (tree cuttings, corn cobs, straw, etc.) do not have these limitations, as they complement pre-established agricultural activity, have a better CO2 balance, et don't interfere with the agro-alimentary cycle. To produce these second generation biofuels, industrialists are looking to develop fungus strains capable of producing a cocktail of cellulases and hemicellulases at a concentration of 50 g/l. Trichoderma reesei is the choice organism for most projects in this field.
Bernard Henrissat's glycogenomic team at the Architecture et fonction des macromolécules biologiques lab specializes in the study of enzymes which break down sugars (2). In order to learn more about the incredible enzymatic activity of Trichoderma reesei, they assayed its genome. Contrary to their expectations, they found that the fungus has only a small number of genes which code for cellulases (hemicellulases and pectinases), many fewer in fact than in usually found in fungi capable of breaking down plant walls. Moreover, the fungus has no or very little enzymatic activity allowing the digestion of specific components in the wall.This was first interpreted as bad news, but the limitations of this model organism are now being seen as something positive. The fungus's enzyme cocktail lends itself to numerous genetic modifications, and researchers are looking into which other enzymes can be added to the fungus's gene sequence in order to make it even more efficient at producing bioethanol.
Julien Guillaume | alfa
Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden
The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy