Secondary metabolites are the origin of a large fraction of drugs used to successfully treat life threatening-illnesses. Because secondary metabolites, their derivatives, or compounds inspired by them are so widespread in the clinic, there remains great enthusiasm for their continued discovery. However, enthusiasm for the work of secondary metabolite discovery has waned because after decades of mining our environment for drug candidates, easily accessible ecosystems have been exhausted, and the methods for discovery currently employed are extremely labor intensive, with a low per-organism compound yield, and the revelation of new chemical diversity has apparently slowed down. However, the recent advent of inexpensive genome sequencing technology has demonstrated unambiguously that efforts to date only scratch the surface of the available natural chemical diversity. Whereas most organisms have generally yielded one or two natural products, genomics has informed us that these same organisms contain the genetic blueprints for many more - ten or twenty times more. But to date few if any facile generalizable methods for eliciting the translation of these blueprints into molecules in tubes have been provided. Herein we tackle two major objectives of opening new ecosystems to natural product discovery and removing the expression bottleneck to accelerate natural product discovery in microorganisms from unusual sources. To accomplish these goals we develop new instrumental, analytical, bioinformatics, and biostatistical methods to capture the information in a comprehensive microbial metabolome that is relevant to new compound discovery and chemical ecology. Our three aims in support of these objectives encompass three major specific aims which are (1) Chemical biogeological survey of secondary metabolism in hypogean (cave) ecosystems, (2) to develop native metabolic activation of biosynthetic processes for discovery, (3) provide an atlas of stimulus to genotype for rational selection of chemical and biological conditions that induce secondary metabolism in organisms with high apparent biosynthetic aptitude. The successful completion of the proposed research is highly relevant to human health because it will provide methods to accelerate the identification of natural products which have had and continue to have a large impact on human health. Furthermore, the discovery of the mode of action of newly discovered and rediscovered compounds for which mode of action has yet to be determined may provide new therapeutics.

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Most potent drugs can trace their origins to a natural product, but the discovery of new natural products is challenging because they are isolated in small quantities from complex organism extracts. We propose to develop and use the tools developed for data mining to help us to identify new natural product drug leads from complex extracts isolated from extreme cave ecosystems with validated high potential for future drug development.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
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Synthetic and Biological Chemistry B Study Section (SBCB)
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Fabian, Miles
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Vanderbilt University Medical Center
Schools of Arts and Sciences
United States
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May, Jody C; Morris, Caleb B; McLean, John A (2017) Ion Mobility Collision Cross Section Compendium. Anal Chem 89:1032-1044
Stow, Sarah M; Causon, Tim J; Zheng, Xueyun et al. (2017) An Interlaboratory Evaluation of Drift Tube Ion Mobility-Mass Spectrometry Collision Cross Section Measurements. Anal Chem 89:9048-9055
Dodds, James N; May, Jody C; McLean, John A (2017) Correlating Resolving Power, Resolution, and Collision Cross Section: Unifying Cross-Platform Assessment of Separation Efficiency in Ion Mobility Spectrometry. Anal Chem 89:12176-12184
Stow, Sarah M; Crescentini, Tiffany M; Forsythe, Jay G et al. (2017) Structural Characterization of Methylenedianiline Regioisomers by Ion Mobility-Mass Spectrometry, Tandem Mass Spectrometry, and Computational Strategies. 3. MALDI Spectra of 2-Ring Isomers. Anal Chem 89:9900-9910
Schrimpe-Rutledge, Alexandra C; Sherrod, Stacy D; McLean, John A (2017) Improving the discovery of secondary metabolite natural products using ion mobility-mass spectrometry. Curr Opin Chem Biol 42:160-166
Dodds, James N; May, Jody C; McLean, John A (2017) Investigation of the Complete Suite of the Leucine and Isoleucine Isomers: Toward Prediction of Ion Mobility Separation Capabilities. Anal Chem 89:952-959
Covington, Brett C; McLean, John A; Bachmann, Brian O (2017) Comparative mass spectrometry-based metabolomics strategies for the investigation of microbial secondary metabolites. Nat Prod Rep 34:6-24
Harper, Brett; Neumann, Elizabeth K; Stow, Sarah M et al. (2016) Determination of ion mobility collision cross sections for unresolved isomeric mixtures using tandem mass spectrometry and chemometric deconvolution. Anal Chim Acta 939:64-72
Tianero, Ma Diarey; Pierce, Elizabeth; Raghuraman, Shrinivasan et al. (2016) Metabolic model for diversity-generating biosynthesis. Proc Natl Acad Sci U S A 113:1772-7
May, Jody C; McLean, John A (2016) Advanced Multidimensional Separations in Mass Spectrometry: Navigating the Big Data Deluge. Annu Rev Anal Chem (Palo Alto Calif) 9:387-409

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