Abstract
The bacterium Myxococcus xanthus provides a good platform to analyze the correlation between gene expression and phenotype. One gene that encapsulates how complex this interaction can be is M. xanthus’s arginine kinase gene. Arriving in the bacterium through horizontal gene transfer, this gene encodes an arginine kinase that plays a role in bacterial growth, stress response, development, and spore formation. However, the true extent of its involvement in these processes is not fully understood, nor is it known what level of arginine kinase expression is needed to produce a wild-type phenotype. As a result, a plasmid was designed to insert the cuoA promoter, which is inducible with copper sulfate, in front of arginine kinase. Several assays were then developed to test M. xanthus’s response to copper during growth and spore development. The performance of wild-type was then compared to an arginine kinase deletion mutant, a cuoAK candidate, and a separate knock-in of a horseshoe crab arginine kinase. While the cuoAK knock-in was unable to be created, the assays demonstrated a safe concentration of copper sulfate that could induce the cuoA promoter without causing cytotoxicity and demonstrated that a higher concentration inhibited numerous functions, reinforcing previous findings. Finally, these assays discovered trends suggesting arginine kinase may help moderate the effects of copper stress, and that the horseshoe crab knock-in had recovered a phenotype close to wild-type M. xanthus in response to copper stress. Should a cuoAK mutant be created in the future, these assays will be useful to test the mutant’s phenotype to find a minimum level of AK expression needed to mimic wild type.
Advisor
Fraga, Dean
Department
Biology
Recommended Citation
Praul, Brian W., "Copper for Your Thoughts?: Examining the Role of Arginine Kinase in Effects of Copper Exposure on Myxococcus xanthus Growth and Sporulation" (2025). Senior Independent Study Theses. Paper 11373.
https://openworks.wooster.edu/independentstudy/11373
Disciplines
Bacteriology | Genetics | Microbial Physiology
Keywords
Myxococcus, RNA Sequencing, Plasmid, Copper, Sporulation
Publication Date
2025
Degree Granted
Bachelor of Arts
Document Type
Senior Independent Study Thesis
© Copyright 2025 Brian W. Praul