Search Dr. Steven’s publications
Education:
- Ph.D. University of Ottawa, Canada
Appointment(s):
- Associate Professor of Pharmacognosy
- Research Associate Professor in the Research Institute of Pharmaceutical Sciences
Interests:
Our research questions and explores the utility provided by specialized metabolites to the producing organism. What do natural products do? The simplicity about this question belies its complexity. While the therapeutic activities of bacterial natural products have driven broad, activity-based discovery efforts, the benefits that the majority of secondary metabolites provide to producing bacteria have been obfuscated by their clinical applications and successes. Investigating the predatory capabilities of myxobacteria, we seek to determine the exchange of specialized metabolites amongst microbes during predation. Developing predator-prey pairings with ecologically relevant prey, we hope to learn how myxobacteria have evolved to combat bacterial behaviors pertinent to clinical concerns such as biofilm formation and persistence.
Current Projects:
Myxobacteria response to exogenous quorum signals & antibiotic discovery from myxobacteria exposed to prey quorum signals and phytohormones (NIAID: R15AI137996)
- Discovered horizontally-acquired, orphan acylhomoserine lactone synthase from Archangium gephyra
- Identified potential role of plant exudates in recruitment of predatory myxobacteria
- Reported that metabolism of Pseudomonas aeruginosa quinolone signals contributes to predatory specialization of Cystobacter ferrugineus
Isolation of myxobacteria from established rhizobiomes & prioritization of novel isolates for antibiotic discovery
- Ongoing isolation of myxobacteria from soils; current collection includes ~60 isolates, 25 sequenced, 4 deposited
- Developed method to prioritize which isolates are targeted for subsequent antibiotic discovery
- Happy to provide genome sequences, BGC data, and isolate stocks to any groups interested in specialized metabolite discovery from myxobacteria; all genome data will eventually be deposited and publicly available
Heterologous expression of targeted biosynthetic gene clusters from newly discovered species of myxobacteria
- Utilize BGC’s from isolated myxobacteria to develop heterologous hosts and discover novel metabolites
Modulation of myxobacterial outer membrane vesicle contents using LPS from various prey (NIGMS: 1P20GM130460 sub-project ID: 7934)
