Wednesday, March 17, 2010

antibiotic resistance

Items damaged antibiotic resistance turned into.
Scientists in the United States have revealed reversible chemical puzzles - puzzles that make microbiologist puzzled experts for many - years: in a colony of bacteria that live in the presence of antibiotics in the natural environment, individuals who are sensitive to antibiotics can live side by side with them ytang be resistant, where logic would dictate that only the resistant bacteria that can survive.

The key to this mystery came back on the antibiotic product is defective, according to recent research by Adam Palmer, Elaine Angelino and Roy Kishony at Harvard University. Scientists learn how the product failed in the emergence of antibiotic tetracycline polyketide naturally affect the population of E. coli exposed to antibiotics.

In this environment, tetracycline, which is produced by Streptomyces bacteria in the soil, naturally broken into several products. This team simulated acid damage from these compounds, by producing the three primary ingredients: stereoisomers of tetracycline called epitetracycline (ETC); together - the same as dehydration products of both itself and tetracycline isomer, called anhydrotetracycline (ATC) and anhydroepitetracycline (AETC ).

Degraded tetracycline into the composition of bioactive compounds, which causes sensitive strain of E. coli strain resistant to release Then, they expose the two tetracycline-resistant strains and tetracycline-sensitive strains of E. coli to antibiotics and product mix breakdown. Typically, where the two populations - sensitive and resistant - are, one would expected that exposure to tetracycline will last from resistant strain. However, in the presence of a defective product will be releasing sensitive strain resistant strain. 'We find that the soup products degraded tetracycline caused tetracycline-resistant bacteria in the competition despite their sensitive cousin,' said Kishony.

One important factor is the degradation products are relatively stable and thus remain exposed to the bacteria they were for some time. This is not usually present in cases in clinical and agricultural areas, where drugs - drugs tend to be cleaned by dilution rather than on degradation.

Precise molecular mechanisms which reverse the degradation products for durability seleski not entirely understood, although what he described as Kishony, 'One of the degradation products, anhydrotetracycline, understood as a potent inducer of the expression of tetracycline efflux pumps [a protein involved in resistance mempompa drugs - drugs kluar of cells - bacterial cells]. An excess production of efflux pumps has a high cost for resistant bacteria."

Julian Davies, a well-known microbial Ecologist at the University of British Columbia in Canada, this study describes as' a brilliant series of studies that have provided an explanation for the success of the survival of sensitive and antibiotic resistant bacteria in the presence of her block. "

Do these findings have clinical significance? 'Unfortunately stereoisomers are toxic to the kidneys, and then not like what was recommended for a therapy, "said Palmer. He added, however, 'This might provide such a lead compound to isolate a compound of non - toxic to select against resistance. More generally these results suggest that derivatives of antibiotics may have the potential to act as a selector against resistance."

Items damaged antibiotic resistance turned into.
Scientists in the United States have revealed reversible chemical puzzles - puzzles that make microbiologist puzzled experts for many - years: in a colony of bacteria that live in the presence of antibiotics in the natural environment, individuals who are sensitive to antibiotics can live side by side with them ytang be resistant, where logic would dictate that only the resistant bacteria that can survive.

The key to this mystery came back on the antibiotic product is defective, according to recent research by Adam Palmer, Elaine Angelino and Roy Kishony at Harvard University. Scientists learn how the product failed in the emergence of antibiotic tetracycline polyketide naturally affect the population of E. coli exposed to antibiotics.

In this environment, tetracycline, which is produced by Streptomyces bacteria in the soil, naturally broken into several products. This team simulated acid damage from these compounds, by producing the three primary ingredients: stereoisomers of tetracycline called epitetracycline (ETC); together - the same as dehydration products of both itself and tetracycline isomer, called anhydrotetracycline (ATC) and anhydroepitetracycline (AETC ).

Degraded tetracycline into the composition of bioactive compounds, which causes sensitive strain of E. coli strain resistant to release Then, they expose the two tetracycline-resistant strains and tetracycline-sensitive strains of E. coli to antibiotics and product mix breakdown. Typically, where the two populations - sensitive and resistant - are, one would expected that exposure to tetracycline will last from resistant strain. However, in the presence of a defective product will be releasing sensitive strain resistant strain. 'We find that the soup products degraded tetracycline caused tetracycline-resistant bacteria in the competition despite their sensitive cousin,' said Kishony.

One important factor is the degradation products are relatively stable and thus remain exposed to the bacteria they were for some time. This is not usually present in cases in clinical and agricultural areas, where drugs - drugs tend to be cleaned by dilution rather than on degradation.

Precise molecular mechanisms which reverse the degradation products for durability seleski not entirely understood, although what he described as Kishony, 'One of the degradation products, anhydrotetracycline, understood as a potent inducer of the expression of tetracycline efflux pumps [a protein involved in resistance mempompa drugs - drugs kluar of cells - bacterial cells]. An excess production of efflux pumps has a high cost for resistant bacteria."

Julian Davies, a well-known microbial Ecologist at the University of British Columbia in Canada, this study describes as' a brilliant series of studies that have provided an explanation for the success of the survival of sensitive and antibiotic resistant bacteria in the presence of her block. "

Do these findings have clinical significance? 'Unfortunately stereoisomers are toxic to the kidneys, and then not like what was recommended for a therapy, "said Palmer. He added, however, 'This might provide such a lead compound to isolate a compound of non - toxic to select against resistance. More generally these results suggest that derivatives of antibiotics may have the potential to act as a selector against resistance."

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