Horizontal gene transfer in Archaea-another article (Introduction)

by David Turell , Wednesday, February 15, 2023, 16:49 (647 days ago) @ David Turell

Nothing really new:

https://www.the-scientist.com/news-opinion/archaea-sport-structures-that-shuttle-genes-...

“'We’ve known for a while that there are a lot of genes that bacteria and archaea exchange,” says Olga Zhaxybayeva, an evolutionary biologist at Dartmouth College who was not involved in the study. If integrons turn out to be widespread in archaea, “it could be another mechanism for microbes to exchange the traits they need.”

"Gene exchange can help bacteria survive in new, harsh environments, or strengthen their symbiotic relationships with plants. Study coauthor Timothy Ghaly, a microbiologist at Macquarie University in Sydney, says that he and his team had always been interested in how integrons allow bacteria to take on novel, sometimes incredibly useful traits such as antibiotic resistance.

"It was unknown if archaea have integrons, partly because they’re hard to study, says Ghaly, as they live in a variety of difficult-to-access environments, from our guts to muddy, sulfuric hot springs. But recent advances in genomic sequencing, in particular a technique used to generate what are known as metagenome-assembled genomes (MAG), have allowed researchers to piece together archaea genomes from environmental samples.

***

"Bacteria swap genes in the form of a gene cassette that consists of a single gene and a gene recombination site called AttC. When they encounter stressful circumstances, bacteria exchange these cassettes like mixtapes, plugging them into and taking them out of their genomes.

***

"In the nearly 6,700 archeal genomes they scanned, the researchers found 75, spanning nine phyla, that had evidence of integrons. All of the archaeal integrons had the same structure and components as bacterial integrons.

"Based on the sequences they found, the researchers then synthesized archaeal AttC-containing cassettes and found that, when exposed, E. coli bacteria incorporated these cassettes into their genomes.

“"It’s always interesting to find [horizontal gene transfer] in new organisms,” says Zhaxybayeva. She adds that, in the future, it would be useful to have a complete genome of a cultured archaea, as opposed to a constructed MAG as the team used in this study, and begin to piece together the mechanism behind the gene transfer. She’s particularly interested in whether archaea in the human gut have integrons, “and whether they participate in the exchange around antibiotic resistance.'”

Comment: not surprising that all bacteria use the same mechanisms of gene transfer.