RT Journal Article
SR Electronic
T1 Metabolic trade-offs hide unforeseen benefits of plasmids carriage
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 810259
DO 10.1101/810259
A1 Rafael C. Reding
YR 2019
UL http://biorxiv.org/content/early/2019/10/18/810259.abstract
AB Microbes can preserve plasmids in non-selective conditions, paying a metabolic cost—reduced growth rate—without getting any benefit from them. Explaining this paradox is challenging. Here I report that plasmids can change multiple traits simultaneously, making them unexpectedly beneficial. A competition between two identical Escherichia coli strains, S and R, where R bears a non-transmissible plasmid with a tetracycline-resistance gene, revealed that growth rate, biomass yield and lag are sensitive to plasmid carriage. Importantly these traits engaged in a trade-off that was previously unknown. R cells exploited it to preserve their plasmid and outgrow their plasmid-free counterpart S—with and without tetracycline. Most of the known plasmids are not transmissible, but they can replicate within their host. The above trade-off can explain the abundance of these plasmids in nature despite lacking horizontal transfer mechanisms.