Electronic Theses and Dissertations

Date of Award


Document Type


Degree Name

Ph.D. in Pharmaceutical Sciences


Pharmaceutics and Drug Delivery

First Advisor

David C. Stevens

Second Advisor

Marc Slattery

Third Advisor

Sudeshna Roy

Relational Format



Gram-negative unicellular myxobacteria, along with their multicellular lifestyle andbiologically active specialized metabolites, are known for the predatory interactions with Gram-negative/ Gram-positive bacteria and fungi. Although myxobacterial predation range have been exploited extensively, little is known about the prey associated molecules contributing to myxobacterial predator-prey dynamics. By employing transcriptomics and untargeted metabolomics approaches, we demonstrate two structurally distinct classes of signaling molecules from Gram-negative bacterial prey elicit significant omics responses from myxobacteria, Myxococcus xanthus and Cystobacter ferrugineus. An overlapping and general response to acylhomoserine lactones, whereas a distinctive response to a quinolone signaling molecule is observed from both myxobacteria. Similarly, by employing transcriptomics and classical microbiological assays, we demonstrate higher production of molecules like pyoverdine, phenazine-1-carboxylic acid, and alginate and resistance to aminoglycosides and tetracycline antibiotics are unique to a predation survivor Pseudomonas putida phenotype. In a predator-prey co-culturing, the predatory stress from myxobacterium C. ferrugineus selects for this P. putida phenotype that eludes subsequent myxobacterial predation. Overall, our study confirms that prey associated chemical components significantly direct responses from predatory myxobacteria.



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