Horizontal gene transfer through plasmids (Introduction)

by David Turell , Thursday, September 14, 2023, 22:20 (435 days ago) @ David Turell

A special plasmid pathway grows and moves slowly:

https://phys.org/news/2023-09-scientists-uncover-ways-bacteria-antibiotic-resistant.html

"Plasmids, found in bacteria and some other microorganisms, are physically separate from chromosomal DNA and can replicate on their own. Bacteria can acquire plasmids from other bacterial cells or from viruses, and as plasmids build up, they give bacteria antibiotic resistance.

"But some plasmids are easier for bacteria to acquire than others. What makes these plasmids spread more easily?

"While common sense might suggest that plasmids that spread the easiest are the ones that allow bacteria to grow the fastest, a new study in Nature Communications, led by Allison Lopatkin, an assistant professor of chemical engineering at the University of Rochester, outlines the surprising evolutionary tradeoff between lag time and growth rate.

***

"Lopatkin and her team studied the growth rates of single colonies of bacteria immediately following plasmid acquisition. Across nearly 60 conditions covering diverse plasmids, selection environments, and clinical strains, they found that intermediate-cost plasmids outcompete both their low and high-cost counterparts.

"The research shows plasmid costs are more complex than previously believed and is a step toward better understanding why certain types of pathogens are better at acquiring plasmids than others. If scientists can understand what controls the costs of acquiring a plasmid, they can potentially use that information to limit the spread of antibiotic-resistant genes.

"'We see horizontal gene transfer as an engineering tool to control how genes can spread and help bacterial communities interact," says Lopatkin. "By understanding the individual parts, we hope not only to be able to fight things like antibiotic resistance, but also to use plasmids to deliver genes that can help natural bacteria degrade oil from oil spills. There are many applications microbiomes can be useful for.'"

Comment: more evidence that at the single-cell-level, a bacterium is the most complicated form of a cell. The original animal at the start of life and through all of evolution an integral part of all developments. Now performing as useful microbiomes. They can extensively edit their own DNA. Other single cells as part of multicellular organisms have specific consigned duties to perform, actively manufacturing proteins and other molecules or monitoring levels of oxygen in the hypothalamus or sodium in the kidney. They do not edit their own DNA.