From ScienceDaily:
Biologist investigates how gene-swapping bacteria evade antibiotics
“One of the prevailing theories for why bacteria make these antibiotic compounds is to fight off competition. But the bacteria that make the antibiotics have to be resistant to those antibiotics. Therefore, many encode antibiotic resistance genes against their own products.”
Random genetic mutation is one way bacteria become antibiotic resistant, but another way is by exchanging antibiotic resistance genes with one another in close quarters, such as in human wounds or on hospital surfaces.
In a recent study, published in June in the Journal of Bacteriology, Palmer and her colleagues shed light on a gene-swapping process called conjugation, which, she tells her students, is like bacterial sex.
“These bacteria utilize an enzyme to chemically scan genetic material within each cell, and at a specific sequence of bases, or ‘letters,’ in the DNA, they add a chemical component called a methyl group, essentially ‘tagging’ that material,” Palmer said. “The methyl group becomes a signal for ‘me’.”
Another enzyme patrols the bacterial cell, and when it finds an untagged DNA sequence that doesn’t belong, the enzyme destroys it. More.
Hmmm.
This sounds like a mechanism for horizontal gene transfer, not like sex, as among animal life forms. The methyl tagging part is interesting. Readers?
Memory lane: Remember when natural selection pure and simple was thought to account for antibiotic resistance?:
How exactly does antibiotic resistance evolve? How have such small and simple organisms managed to repeatedly outpace our drugs? The process is quite simply evolution by natural selection — but bacteria have a few secret weapons that give them an edge. Imagine a population of bacteria infecting a patient in a hospital. The patient is treated with an antibiotic. The drug kills most of the bacteria but there are a few individual bacteria that happen to carry a gene that allows them to survive the onslaught of antibiotic. These survivors reproduce, passing on the gene for resistance to their offspring, and soon the patient is populated by an antibiotic resistant infection — one that not only affects the original patient but that can also be passed on to other patients in the hospital.
See also: Horizontal gene transfer: Sorry, Darwin, it’s not your evolution any more
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“The process is quite simply evolution by natural selection” Isn’t this why people say that evolution is a fact? “But the bacteria that make the antibiotics have to be resistant to those antibiotics. Therefore, many encode antibiotic resistance genes against their own products” – This potentially makes all those people wrong!
“Memory lane: Remember when natural selection pure and simple was thought to account for antibiotic resistance?:”
That pure & simple & wrong belief guided medical science:(
Edit….turn that frown upside down. Antibiotics are a wonderful science discovery. Now when I’m taking them and killing bugs, I can feel happier with all the sex going on? Go forth & multiply.
Curiously, the OP never mentioned horizontal gene transfer (HGT), yet that seems to be what the authors are talking about.
Throwing in the term “sex” sounds confusing. Animal life forms that have sex do not – as a critical part of the process anyway – mess with each other’s genes. Yet that is what is described here. Commonly thought of as HGT.
As it happens, I was not able to find a link to a journal piece, which would certainly have helped matters. Such a piece would likely explain the proposed mechanism according to standard terminology.
Well, we’ll keep the file open.
“Well, we’ll keep the file open.”
Maybe Bill Clinton will weigh in with his thoughts.
notes:
Yes, as you wrote, it’s called conjugation. I guess wikipedia is evil, so you might have overlooked this page.
Bob O’H
“I guess wikipedia is evil”
I know that wikipedia is extremely biased when it comes to the topic of Intelligent Design, but why do you personally think ‘wikipedia is evil’?
Or was that just a rhetorical talking point on your part and you really don’t think wikipedia is evil? If so, why did you say it? And/or does that make you ‘evil’ for trying to create unwarranted deception?
ba77 – I was assuming that readers are intelligent enough to understand rhetoric. It was a tongue in cheek comment.
I’ll wait for Barry to explain if I am objectively evil. I don’t think so, but that’s my subjective opinion.
Bob O’H, I understand perfectly well that rhetorical ploys are mainly used as disingenuous linguistic tricks which are employed to evade what is plainly true.
I consider it a blatant lack of integrity.
And as much as you may disrespect Mr. Arrington’s opinion as to whether something is evil or not, he is not the final arbiter of whether something is objectively evil. (Nor is ‘subjective’ you the final arbiter).
That would be God Himself who you would have to look to, and indeed will look to, for that standard.
And according to Him, i.e. according to Almighty God creator of heaven and earth, we have all fallen short of the glory of God, i.e. we are all are sinners’ and are thus considered ‘evil’ according to his perfect standard of holiness and righteousness.
That is the whole point of the propitiation of Jesus Christ. i.e. To justify fallen man before a perfectly holy and just God.
Notes:
Of peculiar interest to the atheist’s claim that their subjective morality is better than the objective morality of God it that, given atheism, there really is no ‘person’ in the first place in order to have a valid ‘subjective’ opinion about morality, or about anything else for that matter.
of related note, quantum theory entails an irreducible subjective element: