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home:pathogenesis:horizontal_gene [01.03.2012] – external edit 127.0.0.1home:pathogenesis:horizontal_gene [09.14.2022] (current) – external edit 127.0.0.1
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 //**James Lake**, Molecular Biology Institute at the University of California//</blockquote>  //**James Lake**, Molecular Biology Institute at the University of California//</blockquote> 
  
-In fact, due to increasing evidence suggesting the importance of the phenomenon in organisms that cause disease, molecular biologists such as Peter Gogarten at the University of Connecticut have [[http://www.esalenctr.org/display/confpage.cfm?confid=10&pageid=105&pgtype=1|described]] horizontal gene transfer as “a new paradigm for biology."+In fact, due to increasing evidence suggesting the importance of the phenomenon in organisms that cause disease, molecular biologists such as Peter Gogarten at the University of Connecticut have described horizontal gene transfer as “a new paradigm for biology."
  
 Gorgarten insists that horizontal gene transfer is “more frequent than most biologists could even imagine a decade ago” and that this reality turns the idea that we can classify organisms in a simple “[[home:pathogenesis:microbiota#reconsidering_classifying_bacteria_as_species|tree of life]]” on its head. Gorgarten insists that horizontal gene transfer is “more frequent than most biologists could even imagine a decade ago” and that this reality turns the idea that we can classify organisms in a simple “[[home:pathogenesis:microbiota#reconsidering_classifying_bacteria_as_species|tree of life]]” on its head.
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 HGT often happens via plasmids, circular molecules of DNA that can replicate independently of a pathogen’s other genetic material. HGT often happens via plasmids, circular molecules of DNA that can replicate independently of a pathogen’s other genetic material.
  
-There is strong genomic evidence that bacteria often acquire evolutionary novelties from outside their ancestral population by horizontal gene transfer. Researchers at the Cancer Research Institute in Slovakia analyzed the bacterial DNA isolated from the intestinal tract of 11 American and 30 Slovak patients with HIV/AIDS. They found that the intestinal bacteria genes were more than 90% homologous to the corresponding sequence in HIV – suggesting that the bacteria and the HIV virus had traded a significant amount of genetic material.(({{pubmed>long:17984947}}))+There is strong genomic evidence that bacteria often acquire evolutionary novelties from outside their ancestral population by horizontal gene transfer. Researchers at the Cancer Research Institute in Slovakia analyzed the bacterial DNA isolated from the intestinal tract of 11 American and 30 Slovak patients with HIV/AIDS. They found that the intestinal bacteria genes were more than 90% homologous to the corresponding sequence in HIV – suggesting that the bacteria and the HIV virus had traded a significant amount of genetic material.(({{pmid>long:17984947}}))
  
 The following microbes have been documented to evolve, through horizontal gene transfer, certain key evolutionary advantages: The following microbes have been documented to evolve, through horizontal gene transfer, certain key evolutionary advantages:
-  * //Staphylococcus aureus// – resistance to methicillin (an antibiotic) (({{pubmed>long:10348769}})) +  * //Staphylococcus aureus// – resistance to methicillin (an antibiotic) (({{pmid>long:10348769}})) 
-  * //Shigella flexneri// and others – resistance to multiple antibiotics (({{pubmed>long:11544236}})) +  * //Shigella flexneri// and others – resistance to multiple antibiotics (({{pmid>long:11544236}})) 
-  * //Escherichia coli// and others – iron uptake (({{pubmed>long:10675599}})) +  * //Escherichia coli// and others – iron uptake (({{pmid>long:10675599}})) 
-  * //Proidencia rettgeri// – resistance to kanamycin (an antibiotic) (({{pubmed>long:12193633}}))+  * //Proidencia rettgeri// – resistance to kanamycin (an antibiotic) (({{pmid>long:12193633}}))
  
  
 ===== Acquired virulence ===== ===== Acquired virulence =====
  
-The transfer of DNA among pathogens means that once harmless microbes can acquire properties that allow them to cause problems for the host. “The mobile nature of... gene islands, transported between bacteria via plasmids or phages, creates the potential for acquired virulence in previously innocuous microbes,” states researcher Dave Relman of Stanford University. “This concept should inspire some reflection the next time one receives a culture report reading 'normal flora.'”(({{pubmed>long:9779355}}))+The transfer of DNA among pathogens means that once harmless microbes can acquire properties that allow them to cause problems for the host. “The mobile nature of... gene islands, transported between bacteria via plasmids or phages, creates the potential for acquired virulence in previously innocuous microbes,” states researcher Dave Relman of Stanford University. “This concept should inspire some reflection the next time one receives a culture report reading 'normal flora.'”(({{pmid>long:9779355}}))
  
-The bacterial pathogen //Vibrio cholerae// has evolved resistance to a number of antibiotics (none of which are MP antibiotics) in about 10 years' time(({{pubmed>long:14688795}})) passing on to other microbes what researchers have called islands of mobile pathogenecity.(({{pubmed>long:15100694}})) According to Beaber //et al//, when //Vibrio cholerae// is exposed to the antibiotic ciprofloxacin, it will actually promote the spread of antibiotic resistance genes.(({{pubmed>long:14688795}})) +The bacterial pathogen //Vibrio cholerae// has evolved resistance to a number of antibiotics (none of which are MP antibiotics) in about 10 years' time(({{pmid>long:14688795}})) passing on to other microbes what researchers have called islands of mobile pathogenecity.(({{pmid>long:15100694}})) According to Beaber //et al//, when //Vibrio cholerae// is exposed to the antibiotic ciprofloxacin, it will actually promote the spread of antibiotic resistance genes.(({{pmid>long:14688795}})) 
  
 Also, for example, take the bacterial species //Bacillus anthracis//, a species of bacteria that has two plasmids. One plasmid codes for genes that allow the pathogens to create toxins, the other codes for proteins that help it evade the immune system by living inside the white blood cells that kill and digest bacteria. Also, for example, take the bacterial species //Bacillus anthracis//, a species of bacteria that has two plasmids. One plasmid codes for genes that allow the pathogens to create toxins, the other codes for proteins that help it evade the immune system by living inside the white blood cells that kill and digest bacteria.
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 One study looked at several species of insects and roundworms infected by a parasitic bacterium called //Wolbachia pipientis//. The bacterium lives inside  animals’ cells, including their egg cells, giving it ready access to the chromosomes that are passed on to the animals’ offspring. One study looked at several species of insects and roundworms infected by a parasitic bacterium called //Wolbachia pipientis//. The bacterium lives inside  animals’ cells, including their egg cells, giving it ready access to the chromosomes that are passed on to the animals’ offspring.
  
-When the researchers compared the genetic code of the bacterium with the code of 11 other species: four roundworms, four fruit flies, and three wasps, they found that all but three of the fruit fly species had segments of the bacterium’s genetic code embedded in their DNA.(({{pubmed>long:17761848}}))+When the researchers compared the genetic code of the bacterium with the code of 11 other species: four roundworms, four fruit flies, and three wasps, they found that all but three of the fruit fly species had segments of the bacterium’s genetic code embedded in their DNA.(({{pmid>long:17761848}}))
  
 Whether this occurs in humans has not yet been demonstrated, but the bacterial mutation of human DNA is consistent with the Marshall Pathogenesis and might explain the low levels of genetic concordance among people who have the same disease. Whether this occurs in humans has not yet been demonstrated, but the bacterial mutation of human DNA is consistent with the Marshall Pathogenesis and might explain the low levels of genetic concordance among people who have the same disease.
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 ===== Read more ===== ===== Read more =====
  
-  * [[http://bacteriality.com/2008/04/06/genetransfer/|Insights into horizontal gene transfer: conversations with Dr. Peter Gogarten and Dr. James Lake]] <html>&nbsp;</html> [[http://bacteriality.com|{{:home:bacteriality.gif}}]] +  * [[https://bacteriality.com/2008/04/06/genetransfer/|Insights into horizontal gene transfer: conversations with Dr. Peter Gogarten and Dr. James Lake]] <html>&nbsp;</html> [[https://bacteriality.com|{{:home:bacteriality.gif}}]] 
-  * [[http://bacteriality.com/2007/12/30/dnatransfer/|Horizontal DNA transfer also causes bacterial DNA to be passed from generation to generation]] <html>&nbsp;</html> [[http://bacteriality.com|{{:home:bacteriality.gif}}]]+  * [[https://bacteriality.com/2007/12/30/dnatransfer/|Horizontal DNA transfer also causes bacterial DNA to be passed from generation to generation]] <html>&nbsp;</html> [[https://bacteriality.com|{{:home:bacteriality.gif}}]]
  
  
 {{tag> Pathogenesis}} {{tag> Pathogenesis}}
  
 +<nodisp>
 ===== Notes and comments ===== ===== Notes and comments =====
 +
 +//link no longer lads to cited author//
 +[[https://www.esalenctr.org/display/confpage.cfm?confid=10&pageid=105&pgtype=1|described]]
 +
  
   * Legacy content   * Legacy content
-    * http://www.marshallprotocol.com/view_topic.php?id=2810&forum_id=2&jump_to=55165#p55165 e85+    * https://www.marshallprotocol.com/view_topic.php?id=2810&forum_id=2&jump_to=55165#p55165 e85
     *      * 
        
-===== References =====+===== References =====</nodisp> 
home/pathogenesis/horizontal_gene.1325564546.txt.gz · Last modified: 01.03.2012 by 127.0.0.1
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