Zhen Q. Wang examines ways of transforming sugar into hydrocarbons found in gasoline

https://www.buffalo.edu/ubnow/stories/2021/11/wang-sugar-to-hydrocarbons.html.

Zhen Q. Wang, PhD, Assistant Professor, Biological Sciences, University at Buffalo. Photo: Douglas Levere

"Making biofuels from renewable resources like glucose has great potential to advance green energy technology," says biochemist Zhen Q. Wang, assistant professor of biological sciences, College of Arts and Sciences. "Glucose is produced by plants through photosynthesis, which turns carbon dioxide (CO2) and water into oxygen and sugar. So the carbon in the glucose — and later the olefins — is actually from carbon dioxide that has been pulled out of the atmosphere.”  The research project, led by Wang at UB and Michelle C. Y. Chang at UC Berkeley, marks an advance in efforts to create sustainable biofuels. “We combined what biology can do the best with what chemistry can do the best, and we put them together to create this two-step process. Using this method, we were able to make olefins directly from glucose." Read the news story by Charlotte Hsu.

Research News

How sugar-loving microbes could help power future cars

Genetically engineered bacteria can convert glucose into a fatty acid, which can then be transformed into hydrocarbons called olefins. To grow such bacteria, scientists add the microbes to flasks filled with nutrients (the yellow broth) and shake them in an incubator to encourage oxygen flow.

Genetically engineered bacteria can convert glucose into a fatty acid, which can then be transformed into hydrocarbons called olefins. To grow such bacteria, scientists add the microbes to flasks filled with nutrients (the yellow broth) and shake them in an incubator to encourage oxygen flow, as pictured here. Photo: Douglas Levere

By CHARLOTTE HSU

Published November 30, 2021

Print
“Making biofuels from renewable resources like glucose has great potential to advance green energy technology. ”
Zhen Wang, assistant professor
Department of Biological Sciences

It sounds like modern-day alchemy: transforming sugar into hydrocarbons found in gasoline.

But that’s exactly what scientists have done.

In a study in Nature Chemistry, researchers report harnessing the wonders of biology and chemistry to turn glucose (a type of sugar) into olefins (a type of hydrocarbon, and one of several types of molecules that make up gasoline).

The project was led by biochemists Zhen Q. Wang at UB and Michelle C. Y. Chang at the University of California, Berkeley.

The paper, published Nov. 22, marks an advance in efforts to create sustainable biofuels.

Olefins comprise a small percentage of the molecules in gasoline as it’s currently produced, but the process the team developed could likely be adjusted in the future to generate other types of hydrocarbons as well, including some of the other components of gasoline, Wang says. She also notes that olefins have non-fuel applications, as they are used in industrial lubricants and as precursors for making plastics.

Zhen Wang holds a flask containing a strain of E. coli that doesn’t endanger human health.

Zhen Wang holds a flask containing a strain of E. coli that doesn’t endanger human health. Wang and colleagues have shown that genetically engineered E. coli can convert glucose into a class of fatty acids, which can then be transformed into hydrocarbons called olefins. Photo: Douglas Levere

Two-step process

To complete the study, the researchers began by feeding glucose to strains of E. coli that don’t pose a danger to human health.

“These microbes are sugar junkies, even worse than our kids,” Wang jokes.

The E. coli in the experiments were genetically engineered to produce a suite of four enzymes that convert glucose into compounds called 3-hydroxy fatty acids. As the bacteria consumed the glucose, they also started to make the fatty acids.

To complete the transformation, the team used a catalyst called niobium pentoxide (Nb2O5) to chop off unwanted parts of the fatty acids in a chemical process, generating the final product: the olefins.

The scientists identified the enzymes and catalyst through trial and error, testing different molecules with properties that lent themselves to the tasks at hand.

“We combined what biology can do the best with what chemistry can do the best, and we put them together to create this two-step process,” says Wang, assistant professor of biological sciences, College of Arts and Sciences. “Using this method, we were able to make olefins directly from glucose.”

Animation of researcher Zhen Wang checking on genetically engineered bacteria growing in flasks, in an incubator that shakes the flasks.

UB researcher Zhen Wang checks on genetically engineered bacteria growing in flasks in an incubator that shakes the flasks to encourage oxygen flow. Wang and colleagues have shown that genetically engineered microbes can convert glucose into fatty acids, which can then be transformed into hydrocarbons called olefins. Photo animation: Douglas Levere

Glucose comes from photosynthesis

“Making biofuels from renewable resources like glucose has great potential to advance green energy technology,” Wang says.

“Glucose is produced by plants through photosynthesis, which turns carbon dioxide (CO2) and water into oxygen and sugar. So the carbon in the glucose — and later the olefins — is actually from carbon dioxide that has been pulled out of the atmosphere,” Wang explains.

More research is needed, however, to understand the benefits of the new method and whether it can be scaled up efficiently for making biofuels or for other purposes. One of the first questions that will need to be answered is how much energy the process of producing the olefins consumes; if the energy cost is too high, the technology would need to be optimized to be practical on an industrial scale.

Scientists are also interested in increasing the yield. Currently, it takes 100 glucose molecules to produce about 8 olefin molecules, Wang says. She would like to improve that ratio, with a focus on coaxing the E. coli to produce more of the 3-hydroxy fatty acids for every gram of glucose consumed.

In addition to Wang and Chang, co-authors of the study include Heng Song at UC Berkeley and Wuhan University in China; Edward J. Koleski, Noritaka Hara and Yejin Min at UC Berkeley; and Dae Sung Park, Gaurav Kumar and Paul J. Dauenhauer at the University of Minnesota. Park is now at the Korea Research Institute of Chemical Technology.

The research was supported by funding from the U.S. National Science Foundation, the Camille and Henry Dreyfus Postdoctoral Program in Environmental Chemistry and the SUNY Research Foundation.

Faculty Profile

  • Zhen Q. Wang

    PhD

    Zhen Q. Wang, PhD.

    Zhen Q. Wang

    PhD

    Zhen Q. Wang

    PhD

    Assistant Professor
    Undergraduate Fellowship Coordinator

    Research Interests

    Synthetic biology and plant natural products

    Education

    • PhD, Michigan State University
    • Postdoctoral Research, University of California, Berkeley

    Research Summary

    Healing with medicinal plants is as old as humankind itself. Even today, some of the most extensively used drugs such as aspirin, morphine, and quinine are directly extracted from plants. Unlike synthetic drugs, plant natural products are evolutionarily pre-selected chemicals against a wide spectrum of pathogens and other stresses in the environment. However, most plant-based medicines, although biologically effective, have not entered the realm of modern medicine. The biggest challenge is the lack of effective and sustainable methods for producing plant-based medicines because they are present at extremely low concentrations, sometimes less than 0.0001% of fresh weight. The current strategy of farming host plants is unlikely to meet the increasing demand for plant-derived drugs. In addition, these natural products usually have complex chemical structures, and conventional drug synthesis has not been able to produce them in a cost-effective manner.

    The long-term goal in my laboratory is to provide alternative solutions for the sustainable and economical production of plant-based medicines through metabolic engineering and synthetic biology. In particular, we build novel metabolic pathways and reroute native pathways in microorganisms such as E. coli and yeast for the production of plant-derived drugs. Our current focus is terpene, the largest family of plant natural products. Many essential medicines including anti-cancer drug paclitaxel, vinblastine, and vincristine, are terpenes or terpene derivatives. Moreover, a complete understanding of biosynthesis pathways in host plants precedes any engineering efforts for scalable production of plant-based medicines. To this end, we are investigating the missing genes in the biosynthesis of digoxin—an important medicine on the World Health Organization’s (WHO) list of essential medicines for the treatment of heart failure. With the unprecedented technological advancement including DNA synthesis, -omics tools, and genome editing in recent years, we hope to tap into the great diversity of plant natural products to benefit the human health."

    Selected Publications

    • Wang, Z.Q., Song, H., Koleski, E.J. et al. A dual cellular–heterogeneous catalyst strategy for the production of olefins from glucose. Nat. Chem. 13, 1178–1185 (2021). (Link)
    • Mukherjee, M., Carroll, E., Wang, Z.Q.*, Rapid assembly of multi-gene constructs using modular Golden Gate cloning. Journal of Visualized Experiments. Feb. 2021. 168: e61993 (link)
    • Swayambhu, G., Raghavan, I., Ravi, B.G., Pfeifer, B.A.*, Wang, Z.Q.* Salicylate glucoside as a non-toxic plant protectant alternative to salicylic acid. ACS Agricultural Science and Technology, Aug. 2021. (link)
    • Ravi Gopal, B., Guardian, M.G., Dickman, R., Wang, Z.Q.*, High-resolution tandem mass spectrometry dataset reveals fragmentation patterns of cardiac glycosides in leaves of the foxglove plants. Data Brief 2020; 30;105464 (Link)
    • Ravi Gopal, B., Guardian, M.G., Dickman, R., Wang, Z.Q.*, Profiling and structural analysis of cardiac glycosides in two species of Digitalis using high-resolution tandem mass spectrometry. J. Chromatography A, 2020; 1618; 460903 (Link)
    • Wang, Z., Benning, C. Specific Detection and Quantification of Phosphatidic Acid Using the Arabidopsis TGD4 Protein. S. Patent 8,629,251 B2, 2014 (link)
    • Wang, Z., Anderson, N.S., Benning, C. The Phosphatidic Acid Binding Site of the Arabidopsis TGD4 Protein Required for Lipid Import into Chloroplasts Journal of Biological Chemistry 2013; 228(7); 4763-4771 (pdf)
    • Wang, Z., Benning, C. Chloroplast Lipid Synthesis and Lipid Trafficking Through ER-to-Plastid Membrane Contact Sites. Biochemistry Society Transactions 2012; 40(2): 457-63 (pdf)
    • Wang, Z., Xu, C., Benning, C. TGD4 Involved in ER-to-Chloroplast Lipid Trafficking   is a Phosphatidic Acid Binding Protein. The Plant Journal 2012; 70(4): 614-623 (pdf)
    • Wang, Z., Benning, C. Arabidopsis thaliana Polar Glycerolipid Profiling by Thin Layer Chromatography (TLC) Coupled with Gas-Liquid Chromatography (GLC) Journal of Visualized Experiments e2518 (pdf)
    • Roston, R., Moellering E.R., Gao, J, Wang, Z., Muthan, B., Benning, C. Membrane Lipid Metabolism and Trafficking during Chloroplast Development and Maintenance Chemistry and Physics of Lipids 2010; 163; S16 (pdf)