New "Bacteria Bashers" Wipe Out Infection

November 30, 1998

It used to be that antibiotics could be trusted to rid the body of a host of bacterial diseases. Today, however, emerging strains of antibiotic-resistant bacteria are speeding ahead, threatening to make existing drugs obsolete. Now, researchers at the Weizmann Institute of Science have developed an original approach that may lead to a radically new way of treating bacterial infections.

Insects, frogs and, as was recently discovered, humans, have a clever first line of defense against bacterial infections. This defense consists of peptides, or protein fragments, that zap the bacteria, literally spilling their "guts." Prof. Yechiel Shai of the Biological Chemistry Department and his team studied the way these peptides work and found that peptide strategy is as ingenious as it is simple: similar to a detergent or soap that dissolves fatty stains, peptides attach themselves to a bacterium and dissolve a portion of its membrane, which is made of a fatty substance. Once its membrane is punctured, the contents of the bacterium spill out and it dies on the spot.

Having characterized this bacteria-bashing mechanism, Shai's team went on to synthesize novel antimicrobial peptides that are more stable and long-lasting than the natural ones. They hope that these peptides will become the basis for potent antibacterial drugs. Because the new peptide materials kill bacteria instantly, it's unlikely that germs will get a chance to develop resistance against the medication.

Another major advantage of the new peptides is their simplicity. In contrast to antibiotics, which must perform the complicated task of penetrating bacteria and interfering with their functioning, the peptides simply attach themselves to bacterial membranes.

The Weizmann scientists have discovered that peptide attachment depends primarily on chemical composition, not structure. As a result, a synthetic peptide does not require a particularly good fit to be effective. This simplicity should make it relatively easy to produce such peptides in large quantities and to design a large family of these compounds geared to kill different types of bacteria.

Moreover, the peptides should not cause adverse reactions. As opposed to currently available antibiotics, which can destroy cells indiscriminately, the peptide materials have been engineered to kill only bacteria, not body cells. This selectivity is based on the fact that bacterial membranes are negatively charged. The peptides interact only with the negatively charged membranes but not with the neutral charge found on the surface of regular body cells.

The new materials have been shown to work in a test tube, and will soon be tested in laboratory animals. They are being developed for clinical use by a new start-up company, BALM Ltd., created by Pamot Venture Capital Fund and Yeda Research & Development Co. Ltd., the Weizmann Institute's technology transfer arm.
-end-
Luba Vikhanski
Head, Foreign Press Section
Publications and Media Relations Department
Weizmann Institute of Science, Rehovot 76100, Israel
Tel. 972-8-934-3855 (office) 972-3-602-2868 (home)
Fax 972-8-934-4104
Have you visited our Web site? http://www.weizmann.ac.il



American Committee for the Weizmann Institute of Science

Related Bacteria Articles from Brightsurf:

Siblings can also differ from one another in bacteria
A research team from the University of Tübingen and the German Center for Infection Research (DZIF) is investigating how pathogens influence the immune response of their host with genetic variation.

How bacteria fertilize soya
Soya and clover have their very own fertiliser factories in their roots, where bacteria manufacture ammonium, which is crucial for plant growth.

Bacteria might help other bacteria to tolerate antibiotics better
A new paper by the Dynamical Systems Biology lab at UPF shows that the response by bacteria to antibiotics may depend on other species of bacteria they live with, in such a way that some bacteria may make others more tolerant to antibiotics.

Two-faced bacteria
The gut microbiome, which is a collection of numerous beneficial bacteria species, is key to our overall well-being and good health.

Microcensus in bacteria
Bacillus subtilis can determine proportions of different groups within a mixed population.

Right beneath the skin we all have the same bacteria
In the dermis skin layer, the same bacteria are found across age and gender.

Bacteria must be 'stressed out' to divide
Bacterial cell division is controlled by both enzymatic activity and mechanical forces, which work together to control its timing and location, a new study from EPFL finds.

How bees live with bacteria
More than 90 percent of all bee species are not organized in colonies, but fight their way through life alone.

The bacteria building your baby
Australian researchers have laid to rest a longstanding controversy: is the womb sterile?

Hopping bacteria
Scientists have long known that key models of bacterial movement in real-world conditions are flawed.

Read More: Bacteria News and Bacteria Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.