Unraveling the Molecular Complexity of Cellular Machines and Environmental Processes

The Science

Two recent studies demonstrate the enormous potential for scientists to explore extremely complex molecular mixtures and systems frequently encountered in environmental, biological, atmospheric, and energy research.

The Impact

The Environmental Molecular Sciences Laboratory (EMSL), a Department of Energy Office of Science user facility, has an unprecedented ability to routinely analyze large intact proteins, precisely measure the fine structure of isotopes, and extract more information from complex natural organic matter mixtures. One of the world’s most powerful mass spectrometry instruments, a 21 Tesla Fourier transform ion cyclotron resonance mass spectrometer (21T FTICR MS), is now available to the scientific community. Illustrating the power of this new instrument for biogeochemical research, EMSL scientists were able to make over 8,000 molecular formula assignments from dissolved organic matter mixtures using the 21T FTICR MS. In another study, EMSL users rapidly identified and discovered new types of metal-binding molecules known as siderophores, which are produced by bacterial cells.

Summary

As the highest-performance mass spectrometry technique, the FTICR MS has become increasingly valuable in recent years for various research applications. The FTICR MS determines the mass-to-charge ratio of ions by measuring the frequency at which ions rotate in a magnetic field, providing ultra-high resolution and mass measurement accuracy. The 21T FTICR MS, which is one of only two in the world with this high magnetic field strength, went online at EMSL in 2015. In a recent study, a team of EMSL scientists evaluated performance gains produced by this high magnetic field strength. They found this next-generation instrument empowers routine analysis of large intact proteins, precisely measures the fine structure of isotopes, and elicits more information than ever before from complex natural organic matter mixtures. The initial performance characterization of the 21T FTICR MS demonstrates enormous potential for future applications to extremely complex molecular mixtures and systems frequently encountered in environmental, biological, atmospheric, and energy research. Moreover, this unprecedented level of mass resolution and accuracy will help promote widespread use of top-down proteomics—an approach that enables accurate characterization of different protein variants with different biological activity. As a result, this transformative instrument will enable users from around the world to tackle previously intractable questions related to atmospheric, terrestrial, and subsurface processes; microbial communities; biofuel development; and environmental remediation.

Principal Investigator(s)

Ljiljana Paša-Tolic
Environmental Molecular Sciences Laboratory
[email protected]

Funding

This work was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Biological and Environmental Research, including support of the Environmental Molecular Sciences Laboratory (EMSL), a DOE Office of Science user facility, and the “High Resolution and Mass Accuracy Capability” development project at EMSL.

References

J. B. Shaw, T.-Y. Lin, F. E Leach III, A. V. Tolmachev, N. Tolic, E. W. Robinson, D. W. Koppenaal, and L. Paša-Tolic, “21 Tesla Fourier transform ion cyclotron resonance mass spectrometer greatly expands mass spectrometry toolbox.” Journal of the American Society for Mass Spectrometry 27(12), 1929-36 (2016). DOI: 10.1007/s13361-016-1507-9.

L. R. Walker, M. M. Tfaily, J. B. Shaw, N. J. Hess, L. Pasa-Tolic, and D. W. Koppenaal, “Unambiguous identification and discovery of bacterial siderophores by direct injection 21 Tesla Fourier transform ion cyclotron resonance mass spectrometry.” Metallomics (2017). DOI: 10.1039/c6mt00201c.