Horizontal gene transfer: DNA transfer mechanisms (Introduction)

by David Turell , Tuesday, June 19, 2018, 20:44 (2135 days ago) @ David Turell

Horizontal gene transfer is an active system in bacteria, and is controlled by a specific agent in DNA:

https://phys.org/news/2018-06-road-gene-written-dna.html

"A new discovery suggests that bacteria's ability to transfer genes, like those associated with antibiotic resistance, are governed by a previously unknown set of rules that are written in the DNA of the recipient.

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"'In nature, bacteria are constantly exchanging genetic material, even between distant relatives, in a process called horizontal gene transfer, where genetic material is transferred between different species," Dr. Hendrickson says. "The genetic material donated from one bacterium to another may carry novel traits like metabolic pathways, virulence genes and even antibiotic resistance elements."
These "rules" are governed by architecture imparting sequences (AIMS), which are in all bacterial chromosomes. The team discovered that if sets of AIMS are well matched between a donor and recipient genome, then the DNA moving between those genomes can be maintained. The opposite is true if they are not well matched, effectively establishing the "rules of transfer".

"Dr. Henrickson says that when it comes to horizontal gene transfer, AIMS are a little like blood groups for genetic exchange between bacterial species.
"AIMS are most likely to be similar in closely-related bacteria, but when it comes to distant transfer events, there were some surprises. For example, one of our findings was that some species have sequence structures that make them good general donors but very selective recipients, a little like people with group O-blood types."

"Critically, AIMS are easily recognised in all bacterial chromosomes, making possible the prediction of routes of likely gene transfer."

Comment: Horizontal gene transfer is a non-Darwinian way to advance evolution. It looks built-in to drive the process of advancing evolution.