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HGT: Growth of antibiotic resistance termed “bacterial sex”

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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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10 Replies to “HGT: Growth of antibiotic resistance termed “bacterial sex”

  1. 1
    alan777 says:

    “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!

  2. 2
    ppolish says:

    “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.

  3. 3
    News says:

    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.

  4. 4
    ppolish says:

    “Well, we’ll keep the file open.”

    Maybe Bill Clinton will weigh in with his thoughts.

  5. 5
    bornagain77 says:

    notes:

    List Of Degraded Molecular Abilities Of Antibiotic Resistant Bacteria:
    http://www.trueorigin.org/bacteria01.asp

    Is Antibiotic Resistance evidence for evolution? – ‘The Fitness Test’ – video
    https://www.youtube.com/watch?v=rYaU4moNEBU

    Bacterial Conjugation- Transfer of the F Plasmid [HD Animation]
    https://www.youtube.com/watch?v=VU7brO7A36w

    Bacterial conjugation
    https://en.wikipedia.org/wiki/Bacterial_conjugation

    Pilus
    https://en.wikipedia.org/wiki/Pilus

    Scientists unlock a ‘microbial Pompeii’ – February 23, 2014
    Excerpt: “…The researchers discovered that the ancient human oral microbiome already contained the basic genetic machinery for antibiotic resistance more than eight centuries before the invention of the first therapeutic antibiotics in the 1940s…”
    http://phys.org/news/2014-02-s.....mpeii.html

    (Ancient) Cave bacteria resistant to antibiotics – April 2012
    Excerpt: Antibiotic-resistant bacteria cut off from the outside world for more than four million years have been found in a deep cave. The discovery is surprising because drug resistance is widely believed to be the result of too much treatment.,,, “Our study shows that antibiotic resistance is hard-wired into bacteria. It could be billions of years old, but we have only been trying to understand it for the last 70 years,” said Dr Gerry Wright, from McMaster University in Canada, who has analysed the microbes.
    http://www.scotsman.com/news/h.....1-2229183#

    Antibiotic resistance genes are essentially everywhere – May 8, 2014
    Excerpt: The largest metagenomic search for antibiotic resistance genes in the DNA sequences of microbial communities from around the globe has found that bacteria carrying those vexing genes turn up everywhere in nature that scientists look for them,,
    http://www.sciencedaily.com/re.....121347.htm

  6. 6
    Bob O'H says:

    Curiously, the OP never mentioned horizontal gene transfer (HGT), yet that seems to be what the authors are talking about.

    Yes, as you wrote, it’s called conjugation. I guess wikipedia is evil, so you might have overlooked this page.

  7. 7
    bornagain77 says:

    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?

  8. 8
    Bob O'H says:

    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.

  9. 9
    bornagain77 says:

    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:

    Romans 3:23
    for all have sinned and fall short of the glory of God,

    1 John 1:9
    “If we confess our sins he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness”

    Turin Shroud Quantum Hologram Reveals The Words ‘The Lamb’ on a Solid Oval Object Under The Beard – video
    http://www.godtube.com/watch/?v=J21MECNU

    Shroud Hologram – Solid Oval Object Under The Beard
    http://shroud3d.com/findings/s.....-the-beard

    Top Ten Reasons We Know the New Testament is True – Frank Turek – video – November 2011
    (41:00 minute mark – Despite what is commonly believed, of someone being ‘good enough’ to go to heaven, in reality both Mother Teresa and Hitler fall short of the moral perfection required to meet the perfection of God’s objective moral code)
    http://saddleback.com/mc/m/5e22f/

    The Good-O-Meter – The Christian Message in a nutshell – video
    https://www.youtube.com/watch?v=XrLzYw6ULYw

    Falling Plates (the grace of propitiation) – video
    http://www.youtube.com/watch?v=KGlx11BxF24

    Vicki Yohe — Mercy Seat – music
    http://www.youtube.com/watch?v=PXRuK_SJmv0

  10. 10
    bornagain77 says:

    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.

    “What you’re doing is simply instantiating a self: the program run by your neurons which you feel is “you.””
    Jerry Coyne
    https://whyevolutionistrue.wordpress.com/2015/04/04/eagleton-on-baggini-on-free-will/

    The Confidence of Jerry Coyne – Ross Douthat – January 6, 2014
    Excerpt: then halfway through this peroration, we have as an aside the confession that yes, okay, it’s quite possible given materialist premises that “our sense of self is a neuronal illusion.” At which point the entire edifice suddenly looks terribly wobbly — because who, exactly, is doing all of this forging and shaping and purpose-creating if Jerry Coyne, as I understand him (and I assume he understands himself) quite possibly does not actually exist at all? The theme of his argument is the crucial importance of human agency under eliminative materialism, but if under materialist premises the actual agent is quite possibly a fiction, then who exactly is this I who “reads” and “learns” and “teaches,” and why in the universe’s name should my illusory self believe Coyne’s bold proclamation that his illusory self’s purposes are somehow “real” and worthy of devotion and pursuit? (Let alone that they’re morally significant:,,) Read more here:
    http://douthat.blogs.nytimes.c.....oyne/?_r=0

    of related note, quantum theory entails an irreducible subjective element:

    “quantum theory entails an irreducible subjective element in its conceptual basis. In contrast, the theory of relativity when fully exploited, is based on a totally objective view.”
    Sachs – 1986 – On The Comparison Of Quantum and Relativity Theories –

    Does Quantum Physics Make it Easier to Believe in God? Stephen M. Barr – July 10, 2012
    Excerpt: That’s why, when Peierls was asked whether a machine could be an “observer,” he said no, explaining that “the quantum mechanical description is in terms of knowledge, and knowledge requires somebody who knows.” Not a purely physical thing, but a mind.
    https://www.bigquestionsonline.com/content/does-quantum-physics-make-it-easier-believe-god

    The Measurement Problem in quantum mechanics – (Inspiring Philosophy) – 2014 video
    https://www.youtube.com/watch?v=qB7d5V71vUE

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