Fighting back on antibiotic resistance

REHOVOT, Israel, Dec. 29 (UPI) -- Using the mechanisms bacteria and fungi have evolved to resist drugs, Israeli scientists have found an effective way to overcome that resistance.

Researchers at the Weizmann Institute of Science in Rehovot, Israel discovered that all microorganisms produce a natural antimicrobial peptide (AMP) with a positive electrical charge.

The positive charge bonds the AMP to the negatively charged surface of bacteria like a magnet and allows it to carry out its antibiotic mission.

The team combined the AMP with a negatively charged lipopeptide, creating a synthetic lipopeptide with a positive charge and the soap-like ability to dissolve oils.

By altering the length of the lipopeptide's fatty acid chains and the sequence of the AMP's positively charged amino acids, they developed an array of weapons against both bacteria and fungi.

These new synthetic peptides contain only four amino acids, instead of the 12 to 50 amino acids found in their natural forms, so they can be synthesized more cheaply, are less prone to resistance, and can be more easily modified to target a wide range of bacterial and fungal infections.

The study appears in the latest issue of the Proceedings of the National Academy of Sciences.