"The key is the strain's ability to ferment cellobiose and galactose simultaneously, which makes the process much more efficient," Jin said.
Red seaweed, hydrolyzed for its fermentable sugars, yields glucose and galactose. But yeast prefers glucose and won't consume galactose until glucose is gone, which adds considerable time to the process, he said.
The new procedure hydrolyzes cellulose into cellobiose, a dimeric form of glucose, then exploits a newly engineered strain of Saccharomyces cerevisiae capable of fermenting cellobiose and galactose simultaneously.
The team introduced a new sugar transporter and enzyme that breaks down cellobiose at the intracellular level. The result is a yeast that consumes cellobiose and galactose in equal amounts at the same time, cutting the production time of biofuel from marine biomass in half, he said.
The research, performed with project funding from the Energy Biosciences Institute, included team members Suk-Jin Ha, Qiaosi Wei, and Soo Rin Kim of the University of Illinois, Urbana-Champaign, and Jonathan M. Galazka and Jamie Cate of the University of California, Berkeley.
Jin compared the previous process to a person taking first a bite of a cheeseburger, then a bite of pickle. The process that uses the new strain puts the pickle in the cheeseburger sandwich so both foods are consumed at the same time.
Co-fermenting the two sugars also makes for a healthier yeast cell, he said.
"It's a faster, superior process. Our view is that this discovery greatly enhances the economic viability of marine biofuels and gives us a better product," he added.
Is seaweed a viable biofuel? Jin and his colleagues are using a red variety (Gelidium amansii) that is abundant on the coastlines of Southeast Asia. In island or peninsular nations that don't have room to grow other biofuel crops, using seaweed as a source of biofuels just makes good sense, he noted.
But biofuels made from marine biomass also have some advantages over fuels made from other biomass crops, he said.
"Producers of terrestrial biofuels have had difficulty breaking down recalcitrant fibers and extracting fermentable sugars. The harsh pretreatment processes used to release the sugars also result in toxic byproducts, inhibiting subsequent microbial fermentation," he said.
Jin cited two other reasons for use of seaweed biofuels. Production yields of marine plant biomass per unit area are much higher than those of terrestrial biomass. And rate of carbon dioxide fixation is much higher in marine biomass, making it an appealing option for sequestration and recycling of carbon dioxide.
The study appears in Applied and Environmental Microbiology and is available online at www://aem.asm.org/cgi/content/full/77/16/5822.
The Energy Biosciences Institute is a public-private collaboration in which bioscience and biological techniques are being applied to help solve the global energy challenge. The partnership, funded with $500 million for 10 years from the energy company BP, includes researchers from UC Berkeley; the University of Illinois, and the Lawrence Berkeley National Laboratory. Details about the EBI can be found on the website www.energybiosciencesinstitute.org.
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
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