Emily Jeong
Author: Liz Szabo
Published: January 8, 2015
Link: http://www.usatoday.com/story/news/nation/2015/01/08/new-antibiotic-in-soil/21440317/
Summary:
Antibiotics have been used for decades to fight harmful bacteria, but over the many years, the antibiotic-resistance of bacteria has become more common. These strains of bacteria resistant to antibiotics are called superbugs. The rate at which superbugs are appearing are much faster than what the scientists can catch up to. The development of new antibiotics are very difficult (because of financial and scientific reasons), which might lead to what the article calls a "post-antibiotic" era, an era in which former antibiotics won't be effective against any bacteria, resulting in death from formerly treatable infections. However, which the new technology of the iChip, a device that sorts individual bacterial cells within the soil, the scientists were able to finally start studying and testing the bacteria in the soil. Prior to the iChip, they attempted to grow the bacteria in lab dishes, which resulted in a failure. With the iChip, the bacteria were kept in the soil, an environment with which they were familiar. In the iChip, they formed colonies and then were transferred into lab dishes, where they grew very well. After much testing and research, they discovered teixobactin, a compound produced in soil bacteria, was very aggressive against MRSA (methicillin-resistant Staphylococcus aureus) in mice. The introduction of teixobactin as an antibiotic seems promising as scientists did not detect a resistance from the bacteria against it. As exciting as this new finding is, researcher Kim Lewis warns that "human trials are still two years away... Completing those human trials will take three years... Most drugs that appear promising in animals fail to pass human tests." Furthermore, even if teixobactin is effective and safe for human use, it won't be on the market for at least five years.
Connection:
Just recently, we wrote outlines on antibiotics and the resistance to antibiotics that can develop over time within bacteria. This article relates to our current unit of evolution because the superbugs can form through natural selection. In the article, the 70 year use of a compound found in bread mold as an antibiotic is briefly mentioned. The bacteria would adapt to the antibiotic through the condition of the environment. In the presence of an antibiotic, the bacteria that is best fit would survive, and the gene combination that is resistant to antibiotics would be passed down to offspring, increasing the frequency of the antibiotic resistant allele. Teixobactin was only discovered because of the need of a new antibiotic that could kill superbugs that are resistant to the previous antibiotic. Although teixobactin hasn't been tested in humans yet, there is a certain idea that bacteria won't be becoming resistant to it anytime soon.
What bacteria could potentially become immune to antibiotics (and, as a result, what diseases)? Besides the iChip, are scientists taking any steps to stop this evolution of bacteria?
ReplyDeleteTheoretically, all bacteria could become immune to antibiotics, however, the super bugs usually develop in strains of bacteria that have been constantly treated, including staphylococcus aureus. Staphylococcus aureus (SA) is a common type of bacteria that infects wounds, usually having minor effects but could potentially spread to the heart, lungs, and bloodstream. The reason MRSA (a strain of SA resistant to antibiotics) developed its resistance to antibiotics is because it's so common and treated often. Other examples of common super bugs you most likely are familiar with are on this article: http://abcnews.go.com/Health/Wellness/antibiotic-resistance-riskiest-superbugs/story?id=15980356 . In conclusion, all bacteria technically have the potential to adapt to antibiotics and become immune to them, and most will develop immunity to antibiotics at some point.
ReplyDeleteEver since the introduction of antibiotic resistance in the 1930s, scientists have been working on reducing or slowing down the inevitable evolution of bacteria. Although they can't completely stop the bacteria from becoming immune, they attempted to slow it down by proposing strict rules on the use of antibiotics by humans (including the requirement of accurate prescriptions and controlled use of antibiotics in animals and agriculture.) There have been attempts to stop resistance through tracking down how the bacteria becomes resistant (ex. one type pumps the antibiotic out of the cell) and applying specific methods on certain bacteria (ex. continued. scientists tried to keep the antibiotics in the cell somehow, but failed). For more detailed information on the history of attempts on preventing/delaying the evolution of bacteria, read under "HOW TO CONTROL OR REDUCE ANTIBIOTIC RESISTANCE DEVELOPMENT" of this link: http://mmbr.asm.org/content/74/3/417.full
I hope this helps!
Have researchers started thinking the pros and cons of using this on humans? What are the possible health risks of using teixobactin as an antibiotic for humans?
ReplyDelete