Date of Award


Degree Type

Honors College Thesis

Academic Program

Biological Sciences BS


Biological Sciences

First Advisor

Dmitri Mavrodi, Ph.D.

Advisor Department

Biological Sciences


Under certain conditions, the Spartina alterniflora and Juncus roemerianus grasses in marshes undergo progressive decline in an event known as Saltwater Marsh Dieback, which may be attributed to the presence of the plant pathogenic fungi Fusarium. The microbiomes of S. alterniflora and J. roemerianus from Deer Island, MS were characterized and Fusarium suppressing bacteria were identified. Among isolates capable of antagonizing Fusarium were Marinomonas ostreistagni 398 and M. spartinae 468. Despite the progress in understanding the diversity of Marinomonas, our ability to explain ecological, metabolic, and biochemical traits of marinomonads at the genomic sequence level remains limited. Analysis revealed that Marinomonas genomes form three distinct clades supported by the relatedness of orthologous genes. Heterogeneity is reflected in the core genome representing only 50-60% of any individual strain. Genes for the synthesis of siderophores and other secondary metabolites were identified. Clade- and strain-specific genomic regions contained mobile genetic elements. These results provide insights into the genomic diversity of Marinomonas by characterizing genes for the adaptation to hypersaline environments, pathways involved in the interaction with plants, and the production of antimicrobial compounds.

Included in

Genomics Commons