Scientists take step toward more efficient fuel refinement processes

July 31, 2019

Researchers at the Qingdao Institute of Bioenergy and Bioprocesses Technology (QIBEBT) in China have made headway toward more sustainable and economic fuel production by developing a biochemical approach to allow more control over the conversion of natural gas into potable liquid fuel.

The study appeared on July 15 in ACS Catalysis, a journal published by the American Chemical Society.

"The bioconversion of natural gas into liquid fuel has attracted much attention as a promising approach in recent years," said CONG Zhiqi, an author on the paper. "However, the selective hydroxylation of methane -- the main component of natural gas -- has been one of the major challenges for the scientific community." CONG is a professor in the Chinese Academy of Sciences Key Laboratory of Biofuels and the Shandong Provincial Key Laboratory of Synthetic Biology in the Qingdao Institute of Bioenergy and Bioprocesses Technology.

Methane and propane, another component of natural gas, are organic molecules called alkanes. Consisting solely of carbon and hydrogen atoms, alkanes need to be significantly processed before they can be used in fuel. The process includes introducing oxygen and hydrogen, called hydroxyl groups, into the alkane. The atoms rearrange themselves, producing an alcohol that can be used as fuel, such as ethanol.

The process is indirect due to how selective alkanes are when reacting to the hydroxyl catalysts. Researchers have worked on engineering an enzyme that would uniformly speed along the small alkanes reaction to hydroxyl groups needed to produce fuel.

According to Cong, this has been a long-standing issue because of the inability to directly hydroxylate small alkanes. With current processing, some alkanes are too reactive and renders the resulting fuel useless.

In an effort to control which alkanes react and to what degree, CONG and his team focused on several protein variants of P450 monooxygenase, which help the process of introducing hydroxyl groups into alkane molecules. There are more than 41,000 variants of the enzyme, all of which can cause different levels of reaction.

The researchers achieved controllable selective hydroxylation of propane through what CONG calls an artificial P450 system driven by hydrogen peroxide. The system consists of a dual-function small molecule (DFSM), hydrogen peroxide and variants of an engineered P450 enzyme called P450BM3. The engineered P45BM3 is primed to react to the hydrogen peroxide, and the DFSM holds the enzyme and hydrogen peroxide together, allowing the reaction to occur.

The reaction continues over to the propane, successfully converting the alkanes into alcohols that can be turned into fuel. They found the system had comparable or better catalytic properties than the only known peroxide-dependent natural enzyme of small alkanes, depending on which variant of P450BM3 they used.

In engineering the variants, the researchers replaced the substrates on the part of the enzyme that bonds with the hydrogen peroxide with more reactive versions. This helped otherwise inert carbon bonds break apart and bond with other available atoms.

"This study gave the first example of direct small alkane hydroxylation by the peroxide-driven P450BM3 variants. This substantially expands the synthetic toolbox toward the development of a practical catalyst for fuel processing," CONG said.

The researchers are now researching the specific molecular mechanisms of the reactions, and plan to use that information to develop similar systems for use with other natural gas components, such as methane.

"We hope we can further tune the enzyme for use in methane oxidation, as well," CONG said.
Other contributors from the Chinese Academy of Sciences Key Laboratory of Biofuels and the Shandong Provincial Key Laboratory of Synthetic Biology in the Qingdao Institute of Bioenergy and Bioprocesses Technology include CHEN Jie, KONG Fanhui, MA Nana, ZHAO Panxia, LIU Chuanfei and WANG Xiling. CONG, CHEN, MA and ZHAO are also affiliated with the University of Chinese Academy of Sciences.

This work was supported by the National Natural Science Foundation of China, the Qingdao Innovative Leading Talent Project Grant, and the Director Innovation Fund of Key Laboratory of Biofuels of the Chinese Academy of Sciences.

Chinese Academy of Sciences Headquarters

Related Science Articles from Brightsurf:

75 science societies urge the education department to base Title IX sexual harassment regulations on evidence and science
The American Educational Research Association (AERA) and the American Association for the Advancement of Science (AAAS) today led 75 scientific societies in submitting comments on the US Department of Education's proposed changes to Title IX regulations.

Science/Science Careers' survey ranks top biotech, biopharma, and pharma employers
The Science and Science Careers' 2018 annual Top Employers Survey polled employees in the biotechnology, biopharmaceutical, pharmaceutical, and related industries to determine the 20 best employers in these industries as well as their driving characteristics.

Science in the palm of your hand: How citizen science transforms passive learners
Citizen science projects can engage even children who previously were not interested in science.

Applied science may yield more translational research publications than basic science
While translational research can happen at any stage of the research process, a recent investigation of behavioral and social science research awards granted by the NIH between 2008 and 2014 revealed that applied science yielded a higher volume of translational research publications than basic science, according to a study published May 9, 2018 in the open-access journal PLOS ONE by Xueying Han from the Science and Technology Policy Institute, USA, and colleagues.

Prominent academics, including Salk's Thomas Albright, call for more science in forensic science
Six scientists who recently served on the National Commission on Forensic Science are calling on the scientific community at large to advocate for increased research and financial support of forensic science as well as the introduction of empirical testing requirements to ensure the validity of outcomes.

World Science Forum 2017 Jordan issues Science for Peace Declaration
On behalf of the coordinating organizations responsible for delivering the World Science Forum Jordan, the concluding Science for Peace Declaration issued at the Dead Sea represents a global call for action to science and society to build a future that promises greater equality, security and opportunity for all, and in which science plays an increasingly prominent role as an enabler of fair and sustainable development.

PETA science group promotes animal-free science at society of toxicology conference
The PETA International Science Consortium Ltd. is presenting two posters on animal-free methods for testing inhalation toxicity at the 56th annual Society of Toxicology (SOT) meeting March 12 to 16, 2017, in Baltimore, Maryland.

Citizen Science in the Digital Age: Rhetoric, Science and Public Engagement
James Wynn's timely investigation highlights scientific studies grounded in publicly gathered data and probes the rhetoric these studies employ.

Science/Science Careers' survey ranks top biotech, pharma, and biopharma employers
The Science and Science Careers' 2016 annual Top Employers Survey polled employees in the biotechnology, biopharmaceutical, pharmaceutical, and related industries to determine the 20 best employers in these industries as well as their driving characteristics.

Three natural science professors win TJ Park Science Fellowship
Professor Jung-Min Kee (Department of Chemistry, UNIST), Professor Kyudong Choi (Department of Mathematical Sciences, UNIST), and Professor Kwanpyo Kim (Department of Physics, UNIST) are the recipients of the Cheong-Am (TJ Park) Science Fellowship of the year 2016.

Read More: Science News and Science Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to