New Synthetic Compound Message to Drug-Resistant Bacteria: 'Resistance is Futile'

Jan 21, 2009

(PhysOrg.com) -- Scientists at the University of Massachusetts Amherst and the University of Illinois have developed a smart new synthetic compound that not only targets some drug-resistant bacteria and kills them, but the new antibiotic takes away the germs' most potent defense - the mutation that could provide new resistance will also kill them, leaving no escape.

As polymer scientist Gregory Tew at UMass explains, “This newly designed molecule inserts into the cell wall of bacteria and changes its curvature. Instead of forming stable membranes, cells treated with the new antibiotic have increased curvature which makes a hole form in the wall, killing the cell.” Tew says the new antibiotic uses compounds called phenylene ethylnylenes that mimic the body’s own antimicrobial proteins.

“Understanding the details of how this antibiotic works is essential for expanding our tools for fighting infectious diseases,” Tew notes. Bacterial resistance to conventional antibiotics is a major public health problem. Penicillin could once be counted on to kill bacteria that can cause pneumonia, for example, but germs in the Staphylococcus and Enterococcus families have evolved so penicillin no longer works. Now, they’ve also learned to resist newer antibiotics such as tetracycline, streptomycin and gentamicin.

The new compound’s hole-punching ability depends strongly on the presence of a lipid or fat molecule, phosphoethanolamine (PE), found in bacterial cell membranes, he adds. “This new antibiotic likes PE-rich membranes, which is ideal because gram-negative bacteria are rich in PE while human cells are not.”

In their experiment reported in the last 2008 issue of the Proceedings of the National Academy of Sciences, Tew and co-author Gerard Wong of the University of Illinois compared survival rates in two strains of E. coli bacteria grown in separate Petri dishes. One group was engineered so it lacked the PE lipid in its membranes while the other group had the PE layer.

The researchers treated both groups with the new synthetic hole-punching antimicrobial, at the same time giving two more groups a traditional antibiotic, tobramycin that does not attack the PE membrane but rather a cell structure called a ribosome. Results show that the new antibiotic successfully attacked the E. coli strain rich in PE, but it did not work against the other strain without PE. By contrast, tobramycin killed both strains, pinpointing that the bacteria’s vulnerability to the new compound lies in its PE layer.

Provided by University of Massachusetts Amherst

Explore further: Team pioneers strategy for creating new materials

add to favorites email to friend print save as pdf

Related Stories

China's Alibaba plans IPO for week of September 8

5 hours ago

Chinese e-commerce giant Alibaba plans to hold its initial public offering on the US stock market the week of September 8, the Wall Street Journal reported Saturday, citing a person familiar with the matter.

Tablet sales slow as PCs find footing

6 hours ago

Tablets won't eclipse personal computers as fast as once thought, according to studies by market tracker International Data Corporation (IDC).

Startups offer banking for smartphone users

6 hours ago

The latest banks are small enough to fit in the palm of your hand. Startups, such as Moven and Simple, offer banking that's designed specifically for smartphones, enabling users to track their spending on the go. Some things ...

Recommended for you

Team pioneers strategy for creating new materials

Aug 29, 2014

Making something new is never easy. Scientists constantly theorize about new materials, but when the material is manufactured it doesn't always work as expected. To create a new strategy for designing materials, ...

Plug n' Play protein crystals

Aug 29, 2014

Almost a hundred years ago in 1929 Linus Pauling presented the famous Pauling's Rules to describe the principles governing the structure of complex ionic crystals. These rules essentially describe how the ...

Protein glue shows potential for use with biomaterials

Aug 28, 2014

Researchers at the University of Milan in Italy have shown that a synthetic protein called AGMA1 has the potential to promote the adhesion of brain cells in a laboratory setting. This could prove helpful ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

Szkeptik
5 / 5 (1) Jan 21, 2009
They shouldn't say "wall" when they mean "membrane" as bacteria have both and they are two completely different layers made of different materials.

Also the abstract says that mutations would kill them, but I don't see how that would happen. If they could create a strain of bacteria in the lab that lacked PE than evolution can do it too, although getting rid of one of the basic phospholipids entirely will require a sizeable leap.
el_gramador
not rated yet Jan 22, 2009
Hence Szkptik it's actually not a bad idea to use it against bacteria that have evolved resistance. Rather than continue with the same tactics, change the plan and destroy the support beams of the cell. In all likeliness it will be evolved, but to avoid destroying structure and keeping ability is difficult even for the most complex organisms. This might actually be a step in the right direction. Especially given the damaged RNA and DNA can be repaired, while essential components of the cell cannot.