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New theory explains antibiotic mechanism
Issue date: 12/4/08
Antibiotics are likely the most widely used medicines in the world. Early antibiotics were already in use in ancient Egypt and Greece, and it has been over a century since it was discovered that antibiotics kill bacteria.
But remarkably, the precise mechanism by which antibiotics work is still unknown. A research group at Boston University has taken a step toward supporting a new theory of antibiotic activity.
The theory holds that antibiotics introduce free radicals into bacteria. Free radicals are highly energetic particles that can be produced by and result in damage to cells. Scientists are working to determine what role free radicals might play in the functioning of antibiotics.
The Boston University and Howard Hughes Medical Institute group have observed that antibiotics are indeed able to trigger the production of free radicals in bacteria.
"We were interested in understanding more about the pathways and systems that antibiotics utilize, which are involved in cell death following treatment with antibiotics," head of the Boston group Michael Kohanksi said.
"We had shown last year that bactericidal antibiotics, those drugs which kill bacteria, can use a common radical-based pathway which contributes to the killing seen with these drugs. At that point, it was still unclear how different antibiotics with completely different targets can induce a common killing pathway," Kohanski said.
Kohanski's group is concerned with a central question in the study of antibiotics. There are several different classes of antibiotic compounds, each with its own structure, method of delivery into the cell and targets within the cell.
But these diverse drugs all lead to the same endpoint: cell death. Unlocking this conundrum might open the door to newer and better antibiotic compounds. The key seems to be small organelles in bacteria called ribosomes, according to Kohanski's research.
Ribosomes are the site of protein synthesis in all cells. Under normal conditions, ribosomes take in messenger RNA (mRNA), a molecule that basically acts as a mirror copy of the DNA sequence. Ribosomes are able to match up the mRNA sequence to peptides, the single-unit building blocks of proteins, thus creating a specific chain of peptides.
But remarkably, the precise mechanism by which antibiotics work is still unknown. A research group at Boston University has taken a step toward supporting a new theory of antibiotic activity.
The theory holds that antibiotics introduce free radicals into bacteria. Free radicals are highly energetic particles that can be produced by and result in damage to cells. Scientists are working to determine what role free radicals might play in the functioning of antibiotics.
The Boston University and Howard Hughes Medical Institute group have observed that antibiotics are indeed able to trigger the production of free radicals in bacteria.
"We were interested in understanding more about the pathways and systems that antibiotics utilize, which are involved in cell death following treatment with antibiotics," head of the Boston group Michael Kohanksi said.
"We had shown last year that bactericidal antibiotics, those drugs which kill bacteria, can use a common radical-based pathway which contributes to the killing seen with these drugs. At that point, it was still unclear how different antibiotics with completely different targets can induce a common killing pathway," Kohanski said.
Kohanski's group is concerned with a central question in the study of antibiotics. There are several different classes of antibiotic compounds, each with its own structure, method of delivery into the cell and targets within the cell.
But these diverse drugs all lead to the same endpoint: cell death. Unlocking this conundrum might open the door to newer and better antibiotic compounds. The key seems to be small organelles in bacteria called ribosomes, according to Kohanski's research.
Ribosomes are the site of protein synthesis in all cells. Under normal conditions, ribosomes take in messenger RNA (mRNA), a molecule that basically acts as a mirror copy of the DNA sequence. Ribosomes are able to match up the mRNA sequence to peptides, the single-unit building blocks of proteins, thus creating a specific chain of peptides.
Viewing Comments 1 - 2 of 2
who gmp
posted 1/09/09 @ 11:35 AM EST
Good article
keep writing
can you write some thing like this over antibiotic resitance mechanism.
Tom
posted 1/09/09 @ 5:27 PM EST
Nicely written article. One correction, though.
"Ribosomes are able to match up the mRNA sequence to peptides, the single-unit building blocks of proteins, thus creating a specific chain of peptides. (Continued…)
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