A MODIFIED form of penicillin could pave the way for a new range of
antibiotics.
Bacteria have built up resistance to penicillin by producing a defence enzyme
called &bgr;-lactamase. This chops up the active part of the penicillin
molecule—the &bgr;-lactam group—making the drug useless. “Bodyguard”
molecules that inhibit the defence enzyme have been made, but bacteria soon
evolve to deal with them too.
Now a team led by Timothy Smyth of the University of Limerick in Ireland has
built an antibacterial molecule into penicillin’s &bgr;-lactam group. They will say
in a future issue of The Journal of Organic Chemistrythat if the
&bgr;-lactam group is cleaved, it releases another antibacterial agent. “We call
this a checkmate strategy,” says Smyth. “From the point of view of chemical
synthesis, we can have the drugs ready in a year.”
