Matthias Frank | 19-FS-035
This feasibility study aimed to lay further groundwork for studying and understanding how microorganisms interact with each other at the molecular level using model algal-bacterial co-cultures. A better understanding of such interactions is critical to optimizing and operating biotic platforms for a number of applications, including bioenergy, algal bioproducts and agriculture, and carbon capture.
We explored the feasibility of characterizing and following these interactions by identifying and tracking volatile metabolites and biomarkers in the complex gaseous headspace of such cultures. We set up an experimental platform using a co-culture of Phaeodactylum tricornutum and Marinobacter subspecies 3-2 as a model system, used solid-phase microextraction fibers for volatile collection at various time points throughout culture growth, and employed gas-chromatography- mass-spectrometry-based instrumentation available at Lawrence Livermore National Laboratory for compound identification and quantification. We found that it is feasible to determine volatile profiles from the growth of Phaeodactylum tricornutum and Marinobacter subspecies 3-2 using our methodology and to monitor profile changes over time. We also observed that volatiles distinguishing between cultures of the individual species and the co-cultures could be detected.
Project results will feed into Livermore's ongoing research regarding algal-bacterial interactions, and pave the way for future, expanded volatile studies. The approach and technologies developed here will also be applicable and transferable to other microbial communities being studied, such as cyanobacteria, rhizosphere communities, and biofilms.
The results of this feasibility study indicate that measuring volatile organic compound emissions from algal cultures or algal-bacterial co-cultures may be a useful, noninvasive tool for monitoring algal growth and potential synergistic interactions with bacteria. Such a tool will support research on microbial interactions, providing additional capabilities that can support DOE missions in bioenergy, while also supporting the Laboratory's bioscience and bioengineering mission and core competency. Such a tool could also be adapted and applied to much larger culture systems used for biofuel production based on algae. The approach and technologies developed here would also be applicable to research regarding microbial communities that addresses Department of Defense missions.
Publications, Presentations, and Patents
Reese, K. L., et al. 2019a. Chemical profiling of volatile organic compounds in the headspace of algal cultures as early biomarkers of algal pond crashes. Sci. Rep. 9, 13866. doi:10.1038/s41598-019-50125-z. LLNL-JRNL-775406
——— 2019b. "Profiling of Volatile Organic Compounds in the Headspace of Algal Cultures as Biomarkers of Stress or Microbial Symbiosis." Association of Analytical Chemistry Conference in Livonia, MI, November 2019. LLNL-PRES-795758