Bee is for bacterial destruction

Bees are creating a buzz in the world of antibiotic resistance thanks to research by independent teams in Belfast and Cardiff, UK.

Alison Qua and colleagues at Queen’s University, Belfast, found that bee-sting venom contains a key component that can burst bacterial membranes. They found that the chemical, a protein called melittin, breaks open the membranes of all cells, including those in the human body. They hope that, with modification, the chemical could be used to kill antibiotic-resistant bacteria while human cells are left unharmed.

’We have tried to identify residues important in the activity displayed towards different cell membranes and correlate this to changes in the three-dimensional structure of melittin by performing NMR analysis,’ said Qua. ’Cytolytic peptides (like melittin) function almost instantaneously in disrupting cell membranes and it is thought that bacteria will find it very difficult to develop resistance to them.’ Qua presented these data at the Society for General Microbiology’s 155th Meeting at Trinity College Dublin, Ireland, a meeting with a distinctly melliferous flavour.

Also at the meeting, Ana Henriques and her group at the University of Wales Institute, Cardiff, introduced delegates to a surprising property of honey. Manuka honey, made from pollen from the Manuka tree indigenous to New Zealand, appears to be an effective treatment against bacterial infections that form biofilms. If bacteria multiply above a certain level they can form the slimy mass known as a biofilm, which is particularly resistant to antibiotic treatment. Antiseptic dressings impregnated with Manuka honey have been available on prescription and through on-line stockists since the beginning of the year, but their mode of action was unknown.

Henriques and her group grew six different strains of bacteria that formed biofilms and then treated them with Manuka honey. The unattached bacteria were washed off and the antibiotic resistance of the films tested. In all cases, the honey disrupted the biofilms, making them more susceptible to antibiotics.

However, Henriques notes the treatment faces several difficulties, one of them being ’the reluctance of doctors to accept honey as a possible alternative’. But she ends positively: ’Once the mechanisms of action have been fully determined I believe that the medical community will more easily accept honey as a viable alternative.’

Andrew West