TNS Mutagenesis: Ameliorization of the Cost of the Megaplasmid in Pseudomonas Syringae

Abstract

An abnormally large plasmid has been discovered to naturally exist in two strains of Pseudomonas syringae, appropriately called the "Megaplasmid" due to the genetic content of over one million base pairs of DNA. Costs have been observed with the presence of the Megaplasmid, including growth at elevated temperatures. A technique called Tn5 mutagenesis has been utilized to ameliorate the cost to the host. Results show the initial phenotype of Tn5 mutants overcame elevated temperature growth inhibition, but presence of another mutation is likely in order for the strain to grow at elevated temperatures while harboring the Megaplasmid. Further research must be done to identify genes responsible for increased fitness.