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Posted (edited)
Quote

Scientists discover gut bacteria in bees spread antibiotic-resistant genes to each other, It's the kind of thing you might lose sleep over.

 

https://phys.org/news/2017-12-scientists-gut-bacteria-bees-antibiotic-resistant.html

 

Gut bacteria in bees could harbor clues to problems with the gut bacteria of Humans and other animals. 

Quote

How will humans survive serious infections in the future if we're running out of tools today to fight them? Antibiotic resistance among disease-causing bacteria is of global concern, as some last-resort drugs can no longer cure common illnesses such as urinary tract infections.

To make matters worse, researchers from Arizona State University and Norwegian University of Life Sciences have discovered that our very own gut bacteria may be perpetuating the resistance. Scientists uncovered this startling finding while investigating the microbial life in honey bee guts.

"To our surprise, we found that instead of one gut bacterium acquiring resistance and outcompeting all the other gut bacteria in honey bees, the resistance genes spread in the bacterial community so that all strains of bacteria survived," said Gro Amdam, a professor with ASU School of Life Sciences and co-author of the paper.



Read more at: https://phys.org/news/2017-12-scientists-gut-bacteria-bees-antibiotic-resistant.html#jCp

 

 

Edited by Moontanman
Posted

I find it surprising that they found it surprising. After all horizontal gene transfer of resistance cassettes is a well-known phenomenon. To make matters worse, it does not only happen in guts, but also in the environment, as we deliver significant amounts of antibiotics via effluents or manure to free-living bacteria. AB resistance are therefore also spreading in soil bacteria, for example.

Posted
19 hours ago, Moontanman said:

From your quote: To our surprise, we found that instead of one gut bacterium acquiring resistance and outcompeting all the other gut bacteria in honey bees, the resistance genes spread in the bacterial community so that all strains of bacteria survived,"

That's very interesting that they act symbiotically with each other.

Posted

It is not actually that. If you look at the molecular level it is more that the mobile genetic elements carrying the resistance genes (often in form of plasmids, but also transposons) move rapidly between bacteria. Under non-selective conditions they often get lost as they add cost to the host. However, when selection kicks in (i.e. presence of AB) they are maintained and spread further. The bacteria themselves have no advantage per se for sharing resistances (except in cases where the gene product can actively destroy the AB, such as beta-lactamases perhaps).

In some bacteria, natural competence (i.e. active uptake of DNA) under stress conditions could also play a role, though again, mobile genetic elements are the most common source of resistance transfer.

Posted
6 minutes ago, CharonY said:

It is not actually that. If you look at the molecular level it is more that the mobile genetic elements carrying the resistance genes (often in form of plasmids, but also transposons) move rapidly between bacteria. Under non-selective conditions they often get lost as they add cost to the host. However, when selection kicks in (i.e. presence of AB) they are maintained and spread further. The bacteria themselves have no advantage per se for sharing resistances (except in cases where the gene product can actively destroy the AB, such as beta-lactamases perhaps).

In some bacteria, natural competence (i.e. active uptake of DNA) under stress conditions could also play a role, though again, mobile genetic elements are the most common source of resistance transfer.

OK. Cheers.

Posted (edited)
On 12/19/2017 at 1:55 PM, CharonY said:

It is not actually that. If you look at the molecular level it is more that the mobile genetic elements carrying the resistance genes (often in form of plasmids, but also transposons) move rapidly between bacteria. Under non-selective conditions they often get lost as they add cost to the host. However, when selection kicks in (i.e. presence of AB) they are maintained and spread further. The bacteria themselves have no advantage per se for sharing resistances (except in cases where the gene product can actively destroy the AB, such as beta-lactamases perhaps).

In some bacteria, natural competence (i.e. active uptake of DNA) under stress conditions could also play a role, though again, mobile genetic elements are the most common source of resistance transfer.

Ya, CharonY is correct, I was about to say the same-thing about this most bacteria do exchange genes via Plasmid Exchange, which is what our Germ-line sexual reproduction evolved from, this is not surprising despite bacteria still being asexual in reproduction.

YhWY0.png

Edited by Vmedvil
Posted (edited)
15 hours ago, Vmedvil said:

which is what our Germ-line sexual reproduction evolved from

That is a rather bold claim, as the mechanisms are pretty much unrelated. Do you have any sources that claim that? I guess you may have overinterpreted some online articles which may have described it as some primitive form of sexual reproduction. That, however, is also inaccurate as horizontal gene transfer does not result in replication.

Edited by CharonY
Posted (edited)
6 hours ago, CharonY said:

That is a rather bold claim, as the mechanisms are pretty much unrelated. Do you have any sources that claim that? I guess you may have overinterpreted some online articles which may have described it as some primitive form of sexual reproduction. That, however, is also inaccurate as horizontal gene transfer does not result in replication.

I think I said that too. that Plasmid exchange does not cause production but gene transfer. 

 

https://sciencesamhita.com/what-is-bacterial-conjugation/

http://www.pagepress.org/journals/index.php/eb/article/view/eb.2012.e1/6012

Which I would say evolved from a Gene Transfer method to a reproduction mode in plants around 1.3  to 1 Billion years ago branching into fungi and so on.

tree-of-life_2000.jpg

Edited by Vmedvil
Posted
1 hour ago, Vmedvil said:

I think I said that too. that Plasmid exchange does not cause production but gene transfer. 

I was referring specifically to this claim:

 

21 hours ago, Vmedvil said:

Plasmid Exchange, which is what our Germ-line sexual reproduction evolved from

In your link the libertine bubble clearly refers to a parallel development, not one from conjugation as you suggested. AFAIK the origin is still unclear with a number of parallel hypothesis. However, conjugation is a well-developed specialized apparatus and it would be quite difficult to imagine a path from conjugation to meiotic processes. If there was a developed hypothesis indicating how that may have been the case, I would be quite interested in reading up on it. 

 

 

Posted (edited)
45 minutes ago, CharonY said:

I was referring specifically to this claim:

 

In your link the libertine bubble clearly refers to a parallel development, not one from conjugation as you suggested. AFAIK the origin is still unclear with a number of parallel hypothesis. However, conjugation is a well-developed specialized apparatus and it would be quite difficult to imagine a path from conjugation to meiotic processes. If there was a developed hypothesis indicating how that may have been the case, I would be quite interested in reading up on it. 

 

 

Well, since bacteria were here first, I assume that, the thing that Meiosis I  is actually closest to is Protoplast fusion in synthetic biology. 

slide_3.jpg

mitosis-and-meiosis-9-638.jpg.885dfb656632919800cf806b1d8e73c9.jpg

 

protoplast_fusion-14CB9CE1DB4557BDE16.thumb.png.4a66bf1abff91e6c328bb957a159102b.png

But that is a unnatural processes created by man, protoplast fusion. 

Edited by Vmedvil
Posted

Yeah, no that is not related to conjugation. And just as a side note, while the images themselves may be nice, they are quite distracting from the actual point. Which is that the origins of meioisis are apparently not quite clear and one can definitely not state with any level of certainty that they originated from conjugation. 

Posted (edited)
7 minutes ago, CharonY said:

Yeah, no that is not related to conjugation. And just as a side note, while the images themselves may be nice, they are quite distracting from the actual point. Which is that the origins of meioisis are apparently not quite clear and one can definitely not state with any level of certainty that they originated from conjugation. 

I know, I was just saying that is what it is closest to, which cannot be what caused it as it is man-made process, Protoplast fusion. 

Edited by Vmedvil
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