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dr.syntax

CONJUGATION: bacteria can transfer DNA to eukaryotes

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That was news to me,bacteria being able to exchange DNA with eukaryotic cells. I was unaware of that fact. Bacteria can also exchange DNA inter-specially. That means between different species of bacteria by way of this method called conjugation. There are two other ways bacteria have of exchanging DNA amongst other bacteria. If you would like to learn more about all this go to : http://www.slic2.wsu.edu:82/hurlbert/micro101/pages/chap9.html . There are some interesting aspects to all this and much to learn at this website. There are some important practical aspects to bacteria`s ability to transfer genetic material by conjugation. A single cell carrying an anti-biotic resistant plasmid can infect many other cells with this plasmid, thereby spreading anti-biotic resistant plasmids rapidly throughout a bacterial population. Plasmids are packets of DNA. This information has been paraphrased by me from information gathered by me at the website given above. ...Dr.Syntax

Edited by dr.syntax
addition

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Conjugation relies on a specific machinery in either pro- or eukaryotes. They are unable to conjugate with each other. Horizontal gene transfer between the kingdoms is dependent on other mechanisms. However, is there anything specific that you want to understand or discuss?

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Conjugation relies on a specific machinery in either pro- or eukaryotes. They are unable to conjugate with each other. Horizontal gene transfer between the kingdoms is dependent on other mechanisms. However, is there anything specific that you want to understand or discuss?

 

REPLY: You either did not read what was clearly stated as factual at the website I provided or disagree with it. For what it is worth, that website is an online course in micro-biology. I myself would be very reluctant to reject statements from people teaching an online course such as this. It appeared to me they considered it general knowledge, because no attributions were cited as would be the case if what they were stating as fact; was not generally agreed upon by their contemporaries in that field, Did you read that website ? It is presented as a part of an online course in biology. Not as some theory being kicked around by some biologists. According to them these facts about CONJUGATION have been known about for quite a while now. I`ll reread the part that dates when these discoveries were first made and edit it into this posting. This is directly quoted from the website I provided in the section titled : CONJUGATION

QUOTE: " The ability of bacterial cells to transfer DNA between cells that are in physical contact, as a form of DNA exchange between bacteria in the 1950s stunned scientists and lay people alike. It`s obvious anthropomorphic simularity to mamalian gene exchange amused some and shocked others. Since it`s discovery, conjugational exchange exchange of DNA has been shown to be more common and promiscuous than first thought possible. Initially, conjugation was thought to occur only between the same or closely related species, but data has accumulated wich shows that conjugation between bacteria crosses prokaryotic species lines and even occurs between bacteria and some eukaryotic cells. How pervasive this later situation is remains to be determined. " UNQUOTE

I want you to know this effort on my part to transcribe and type in this quote was both time consuming and tedious for me. I will not be doing any more of this for anyone who won`t bother to read the websites I provide. ...Dr.Syntax

Edited by dr.syntax

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You were not completely clear about your aim for the thread. However, I think you have made a finding that has been known for some time. The case of the Ti plasmid when Agrobacterium tumefaciens passes on its genes to certain plants is a classic example.

 

In eukaryotes, a few examples of horizontal gene transfer have been well documented. Eukaryote-to-eukaryote horizontal transfer of mitochondrial genes has been recently reported between parasitic plants and their plant hosts (33). Two examples of interkingdom horizontal transfer from prokaryotes to eukaryotes are also well known: the transfer of genetic information by Agrobacterium tumefaciens into its plant symbiont (59) and the transfer of genetic information from mitochondria and chloroplasts to the nuclear genome (19). Beyond these two special cases, however, the frequency of transfer of genetic information from bacteria into eukaryotes, though postulated in a number of cases, is still a matter of debate. Prokaryotic genomic sequencing has revealed horizontal gene transfer as an important evolutionary mechanism among these organisms (30, 37). As the number of available sequenced eukaryotic genomes increases, these data can be used to determine the existence and/or frequency of horizontal gene transfer in specific lineages. Several cases of horizontal gene transfer from prokaryotes to microbial eukaryotes have been previously postulated including the 3-hydroxy-3-methylglutaryl-coenzyme A class 2 reductase found in Giardia (6), iron hydrogenase found in Nyctotherus (20), and the fungal catalases (see references 24 and 27 for reviews). A recent report by Dujon et al. (13) suggests that eight genes from Yarrowia lipolytica, five genes from Kluyveromyces lactis, and one gene from Debaryomyces hansenii are horizontally transferred. The phylogeny of horizontally transferred genes is characteristically different from the species phylogeny; these phylogenetic differences can also arise by means other than horizontal gene transfer such as accelerated gene evolution, gene loss, or horizontal transfer from a eukaryote to a prokaryote. Differences can also result from species misassignment of sequences due to DNA contamination. Cases of accelerated gene evolution in Saccharomyces cerevisiae, such as the gene for kinesin (31), and of gene loss (7) have been documented. Thus, to demonstrate that a gene has entered the S. cerevisiae or A. gossypii lineages by horizontal gene transfer, it is necessary to construct an extensive gene phylogeny to rule out potential alternative explanations such as those listed above.

 

http://ec.asm.org/cgi/content/full/4/6/1102

 

Would you please cross-reference, read the papers and discuss with us. Thanks. Jimmy

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The transfer between pro- and eukaryotes often depends on type four secretion systems. The actual transfer is somewhat different between eu- and prokaryotes, though. The transfer of the ti-plasmid between bacteria, for instance relies on different mechanisms than the transfer to the plant host cell. As such I would assign different names to the underlying mechanisms. Though I think around 2000 there was a high-ranking paper that described the acquisition of plasmid DNA from bacteria by a hamster cell. I believe the author ( I cannot recall the name right now) also referred to this mechanism as conjugation, although the actual transfer was not observable. As I originally came from the prokaryotic side may definition may be a bit more stringent.

It is an interesting topic, though and I would be happy if anyone would like to discuss anything in that regard

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That was news to me,bacteria being able to exchange DNA with eukaryotic cells. I was unaware of that fact. Bacteria can also exchange DNA inter-specially. That means between different species of bacteria by way of this method called conjugation. There are two other ways bacteria have of exchanging DNA amongst other bacteria. If you would like to learn more about all this go to : http://www.slic2.wsu.edu:82/hurlbert/micro101/pages/chap9.html . There are some interesting aspects to all this and much to learn at this website. There are some important practical aspects to bacteria`s ability to transfer genetic material by conjugation. A single cell carrying an anti-biotic resistant plasmid can infect many other cells with this plasmid, thereby spreading anti-biotic resistant plasmids rapidly throughout a bacterial population. Plasmids are packets of DNA. This information has been paraphrased by me from information gathered by me at the website given above. ...Dr.Syntax
So the idea that the selection goddess kills off all the non-resistant bacteria, and they are replaced would seem to be yesterday's myth. Who'dve ever predicted life even just might maybe be equipped to adapt without recourse to either mutation or selection?

 

I'll donate another link to the cause:

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/Avery.html

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The transfer between pro- and eukaryotes often depends on type four secretion systems. The actual transfer is somewhat different between eu- and prokaryotes, though. The transfer of the ti-plasmid between bacteria, for instance relies on different mechanisms than the transfer to the plant host cell. As such I would assign different names to the underlying mechanisms. Though I think around 2000 there was a high-ranking paper that described the acquisition of plasmid DNA from bacteria by a hamster cell. I believe the author ( I cannot recall the name right now) also referred to this mechanism as conjugation, although the actual transfer was not observable. As I originally came from the prokaryotic side may definition may be a bit more stringent.

It is an interesting topic, though and I would be happy if anyone would like to discuss anything in that regard

 

REPLY: The ability of prokayotes to transfer DNA material to eukaryotes by means of CONJUGATION was discovered in the 1950s as is discussed in the website article posted in the original posting of this thread. ...DS


Merged post follows:

Consecutive posts merged
REPLY: The ability of prokayotes to transfer DNA material to eukaryotes by means of CONJUGATION was discovered in the 1950s as is discussed in the website article posted in the original posting of this thread. ...DS

 

 

REPLY:Bacterial CONJUGATION FIRST DISCOVERED IN 1946 BY: Joshua Lederberg and Edward Tatum. My source is NationMaster.com . They had a long list of reference material and no way for me to know which of their sources came up with this specific information.

I have been unable to find out who and when eukaryotic to prokaryotic conjugation was first discovered. ...Dr.Syntax

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On 10/17/2009 at 4:54 AM, dr.syntax said:

That was news to me,bacteria being able to exchange DNA with eukaryotic cells. I was unaware of that fact. Bacteria can also exchange DNA inter-specially. That means between different species of bacteria by way of this method called conjugation. There are two other ways bacteria have of exchanging DNA amongst other bacteria. If you would like to learn more about all this go to : http://www.slic2.wsu.edu:82/hurlbert/micro101/pages/chap9.html . There are some interesting aspects to all this and much to learn at this website. There are some important practical aspects to bacteria`s ability to transfer genetic material by conjugation. A single cell carrying an anti-biotic resistant plasmid can infect many other cells with this plasmid, thereby spreading anti-biotic resistant plasmids rapidly throughout a bacterial population. Plasmids are packets of DNA. This information has been paraphrased by me from information gathered by me at the website given above. ...Dr.Syntax

الرابط لا يعمل 

 

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5 minutes ago, Abdulla said:

الرابط لا يعمل 

Given that this thread is 11 years old and that guy who posted the link was a massive nut job, it’s probably good that it no longer works 

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20 minutes ago, iNow said:

Given that this thread is 11 years old and that guy who posted the link was a massive nut job, it’s probably good that it no longer works 

Does the process of coupling between prokaryotic and eukaryotic cells occur and how? ?

 

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