The most densely populated body part is also a swing carrier for genes, even for those who are resistant to antibiotics
Bacteria form a global genetic net and exchange DNA with each other. This possibility of spontaneous genetic engineering increases and accelerates the adhesion opportunities certainly in coarse MAB. Scientists could now observe that even in our densely populated intestines a violent barter between the locals and food taken up with the food, which will sometimes continue to be given to antibiotics resistant.
The scientists from the University of Illinois have as they "Evidence For Extensive Resistance Gene Transfer Among Bacteroides SPP. and among bacteroides and other genera in The Human Colon" (Appl. Environ. Microbiol. 2001. 67: 561-568) Writing, allegedly canceled for the first time this swimming trade in our intestines can be demonstrated: "We have shown that resistance genes for antibiotics", So Abigail Saylers, "can hike in the human colon. In the colon, the gene exchange occurs in an amazing order. There is a lot of bacterial furniture off."
The colon is the most densely populated body part. To the 1012 bacteria from up to 500 different types live here in one gram. Some defend their habitat against invaders or adhere to the intestinal goods so that they can not leave room for immigrants. Bacteria not only inherit our innards, they also influence them by, for example, as Bacteroides ThetioTAOMICRON urge the metabolism of the intestinal cells to their favor. Overall, it must be quite Darwinian here, even if the food, at least in the hosts in the rich countries, is usually abundant. However, they often have to be aware of poisonous or indigestible surviving that they are suspended. Sometimes aggressive bacteria like some stages of E. Coli in the intestine and produce toxins. Diarrhea then is called that the local population has drawn the shorter and is outlined.
If then at this densely populated place, which is still distinguished by immigration and emigration waves, is also a violent exchange of swairs in progress, in which random DNA-stucco changed the owner, then it can be of course dangerous if we are always through the food back against antibiotics absorb resistant bacteria that pass on their genes to the intestinal inhabitants (genetically changed plants are not immaic?To). The exchange of genetic material has nothing to do with reproduction here, but the conjugation is a form of sexual behavior, in which two bacteria are jerking together and exchanging in a plasma milling in hereditary material (horizontal, as it says) Then install in your genome.
The scientists have to check the thesis of gene exchange, bacteroids, ie certain intestinal bacteria collected in 1980 by the Anaerobic Laboratory of the Virginia Polytechnic Institute, with the same bacterial stems, especially with regard to resistance genes, the end of the 90s of individuals or medical Centers came. The result was that a significant increase in resistance to the tetracycline antibiotics could be detected, which was caused by a gene that exist in the 1970s in 23 percent of the samples, but already in more than 80 percent of the samples in the 1990s was. A less strong increase in resistance that AF is back to two genes was detected against erythromycin. "Because the same travel fingers were found in a variety of bacteroid species, we believe", so salyers, "that this increase owes itself to the horizontal gene transfer over the period of three decades."
Even if you can remember without coarse, if animals that serve the consumption, antibiotics are administered in coarse quantities or introduced into genetically modified crops of resistance genes, proving the detection of the gene exchange that it should not be played around: "For example, one feeds a pig for a long time with antibiotics. The bacteria in the digestive tract are resistant to the antibiotics. Then the pig is slaughtered and brought to the market. The bacteria get into the meat products. The consumer takes you home and eats these bacteria. A horizontal transfer can take place in now one hour."
Of course, not only the intestinal bacteria can accommodate the resistance genes, they can also pass the genes other, truly dangerous bacteria that can not be destroyed with antibiotics. And that is getting back to the problem.
Salyers suspects that a reason could be due to the amplified sex of bacteria in the antibiotics themselves. So the tetracycline should trim out horizontal gene transfer: "Tetracycline are an aphrodisiac for bacteria and bring them further to give the resistance genes. This suggests that this orgy of horizontal gene transfer could have to do with the widespread spread of the tetracycline in humans during the last decades." But that is still a guess, which must be investigated as well as the question of whether other bacteria as the bacteroids in our body organize a similar exchange trading or a comparable orgy.