The danger posed by bacteria becoming increasingly resistant to antibiotics has been brought to the attention of the G8 nations by the UK’s Chief Medical Officer, Dame Sally Davies. She warns that even routine operations could become risky within 20 years if the world fails to develop a new generation of antibiotics. One potential source is the human body, which makes natural germ-killing substances known as antimicrobial peptides. About 1,700 of these peptides have been detected including dermcidin, produced in sweat to disinfect cuts and grazes. Dermcidin kills bacteria by making holes in their surface – a strategy that is difficult for bugs to evolve defences against. Scientists recently studied how these holes are formed and the computer simulation pictured shows peptide molecules in orange and dark blue, forming a channel into the cell. This hole allows ions to flow uncontrollably across the cell membrane, with fatal results.
Written by Mick Warwicker
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