Navigation Links
Evolution follows few of the possible paths to antibiotic resistance

Darwinian evolution follows very few of the available mutational pathways to attain fitter proteins, researchers at Harvard University have found in a study of a gene whose mutant form increases bacterial resistance to a widely prescribed antibiotic by a factor of roughly 100,000. Their work indicates that of 120 harrowing, five-step mutational paths that theoretically could grant antibiotic resistance, only about 10 actually endow bacteria with a meaningful evolutionary advantage.

The research is published in the journal Science.

"Just as there are many alternate routes one might follow in driving from Boston to New York, one intrinsic property of DNA is that very many distinct mutational paths link any two variants of a gene," says lead author Daniel M. Weinreich, a research associate in Harvard's Department of Organismic and Evolutionary Biology. "Although this fact has been recognized for at least 35 years, its implications for evolution by natural selection have remained unexplored. Specifically, it is of great interest to determine whether natural selection regards these many mutational paths equivalently."

Weinreich and colleagues generated a series of mutants found along all 120 possible mutational trajectories involving the gene coding for the enzyme beta-lactamase, which in altered form can serve to inactivate antibiotics including penicillin and cefotaxime. Analyzing how well each variant protected host Escherichia coli cells against treatment with various concentrations of antibiotic, the scientists found that only a very small fraction of these pathways confer ever-increasing resistance in pathogenic microbes, and are therefore relevant to natural selection.

Resistance-granting mutations of beta-lactamase occur in a five-step process, with the 120 possible mutational paths representing all the possible ways in which these five point mutations can occur. Fully 102 of the 120 trajectories are inaccessible to natural selectio
'"/>

Source:Harvard University


Page: 1 2

Related biology news :

1. To Stop Evolution: New Way Of Fighting Antibiotic Resistance Demonstrated By Scripps Scientists
2. Evolution of taste receptor may have shaped human sensitivity to toxic compounds
3. Evolution of life on Earth may hold key to finding life in outer space
4. Evolutionary conservation of a mechanism of longevity from worms to mammals
5. Evolutionary biology research techniques predict cancer
6. Evolutionary shifts in olfactory sensitivities in fruit flies
7. Evolution mystery: Spider venom and bacteria share same toxin
8. Evolution of irreducible complexity explained
9. Evolutionary scrap-heap challenge: Antifreeze fish make sense out of junk DNA
10. Evolutionary forces explain why women live longer than men
11. Evolution reveals an independent route for diversity in animal form
Post Your Comments:
*Name:
*Comment:
*Email:
TAG: Evolution follows few the possible paths antibiotic resistance

(Date:9/19/2014)... regulate their symbiotic relationship with soil bacteria by ... plant structure from leaves into the roots to ... roots. This collaborative study was conducted by researchers ... Graduate University for Advanced Studies (SOKENDAI), and the ... , Legumes, an important plant family which ...
(Date:9/18/2014)... Miranda, a small, icy moon of Uranus, is ... in the solar system. Despite its relatively small size, ... resurfacing that resulted in the formation of at least ... called coronae. , These coronae are visible in ... 200 km across. Arden corona, the largest, has ridges ...
(Date:9/18/2014)... starts a "frequent flyers" program, fruit flies surely would ... has hosted increasing numbers of fruit fly research studies. ... in April, and another is scheduled launch to the ... launch in December. , Fruit flies are biomedical research ... space. Model organisms can reveal the basis for health ...
Breaking Biology News(10 mins):For legume plants, a new route from shoot to root 2Miranda: An icy moon deformed by tidal heating 2Miranda: An icy moon deformed by tidal heating 3Miranda: An icy moon deformed by tidal heating 4Miranda: An icy moon deformed by tidal heating 5Miranda: An icy moon deformed by tidal heating 6Miranda: An icy moon deformed by tidal heating 7Buzzing with activity: Fruit flies orbit Earth for science 2Buzzing with activity: Fruit flies orbit Earth for science 3Buzzing with activity: Fruit flies orbit Earth for science 4
... a type of cell that is the "missing link" between bone ... system, a finding that will lead to a greater understanding of ... lead to poor immune function. The studies were done using ... blood during postnatal life. "We felt it was especially important ...
... for treating burn victims to a technique for detecting ... now being developed with support from the University of ... program announced that it is awarding funding to five ... to improve health care. The new funding is ...
... New research published in BioMed Central,s open access journal ... into an ornamental plant ( Pelargonium ), can produce long-lived ... have been cultivated in Europe since the 17th century and ... plants around the world. They have been selectively bred to ...
Cached Biology News:UCLA researchers discover missing link between stem cells and immune system 2UCLA researchers discover missing link between stem cells and immune system 3MU celebrates $5 million partnership for advancing biomedical discoveries 2MU celebrates $5 million partnership for advancing biomedical discoveries 3No more sneezing, allergen-free house plants 2
(Date:9/18/2014)... HealthTronics, Inc ., a leading ... and services, announced that a poster related to ... external beam radiotherapy (EBRT) is being presented at ... (MAAUA) Annual Meeting in Baltimore, Maryland September 18-21, ... and External Beam Radiation as Treatments for Localized ...
(Date:9/18/2014)... 2014 A novel robotic system that ... is currently being tested as part of a biomedical ... Boston with the aim of determining if the robot, ... cancer biopsies faster, more accurate, less costly, and less ... the potential to deliver prostate cancer therapies with greater ...
(Date:9/18/2014)... Station, Texas (PRWEB) September 18, 2014 ... System Chancellor John Sharp, Texas A&M Health Science ... the U.S. Department of Health and Human Services ... today dedicated a national pandemic influenza vaccine manufacturing ... serve as an anchor for the Texas A&M ...
(Date:9/18/2014)... -- Research and Markets has announced ... Report 2014" report to their offering. ... is a professional and in-depth study on the ... The report provides a basic overview of ... chain structure. The N-acetylcysteine market analysis is provided ...
Breaking Biology Technology:HealthTronics Announces Data Comparing Cryotherapy Versus Radiation for Treating Prostate Cancer Poster Presented at the American Urological Association Regional Meeting 2Worcester Polytechnic Institute Participates in Clinical Trial for MRI-Compatible Robot Designed to Improve Accuracy of Prostate Cancer Biopsies 2Worcester Polytechnic Institute Participates in Clinical Trial for MRI-Compatible Robot Designed to Improve Accuracy of Prostate Cancer Biopsies 3Worcester Polytechnic Institute Participates in Clinical Trial for MRI-Compatible Robot Designed to Improve Accuracy of Prostate Cancer Biopsies 4Worcester Polytechnic Institute Participates in Clinical Trial for MRI-Compatible Robot Designed to Improve Accuracy of Prostate Cancer Biopsies 5Worcester Polytechnic Institute Participates in Clinical Trial for MRI-Compatible Robot Designed to Improve Accuracy of Prostate Cancer Biopsies 6Texas A&M Dedicates National Pandemic Influenza Vaccine Manufacturing Facility, on Track for 2016 Start-Up Phase 2Texas A&M Dedicates National Pandemic Influenza Vaccine Manufacturing Facility, on Track for 2016 Start-Up Phase 3Texas A&M Dedicates National Pandemic Influenza Vaccine Manufacturing Facility, on Track for 2016 Start-Up Phase 4Global N-acetylcysteine Industry Report 2014 2
... legislators who must pass judgment on a major building project ... "How will it help Wisconsin and my district?" Governor ... is providing some straightforward, and exciting, answers. , ,Plans for ... with half public money and half private gifts, will come ...
... when they're near a reader and can store ... its history, quantity, location and condition. In ... companies are scurrying to develop strategies for implementing ... from Wal Mart and the U.S. Department of ...
... In his February 14, 2005 article, Michael Rosen argues ... strategy," and suggests that this will be a good ... strategy for traditional pharmaceuticals. This strategy has not been ... will be well-served if Big Pharma adopts this same ...
Cached Biology Technology:How the Institute for Discovery will help Wisconsin 2How the Institute for Discovery will help Wisconsin 3UW-Madison workgroup helps state companies tap the power of RFID 2UW-Madison workgroup helps state companies tap the power of RFID 3UW-Madison workgroup helps state companies tap the power of RFID 4Big Pharma already has a generic strategy, but needs new direction 2Big Pharma already has a generic strategy, but needs new direction 3
... The EC570-90 is a compact, lightweight, high ... 500 volts or 2500 milliamps. It is an ... RNA submarine gels. It is also ideal for ... time can be set to automatically end a ...
Rat Hepatocytes (RH) (>3,000,000 cells)...
QCPN...
Rat Aortic Smooth Muscle Cells (RAOSMC) (>500,000 cells)...
Biology Products: