Just a spoonful of sugar can impart that killing edge to antibiotics against infections. Researchers found that glucose and fructose -- types of sugar found in plants -- make deadly bugs behind chronic infections more vulnerable to drugs. Sugar can improve the effectiveness of antibiotics against infections, say researchers. Such infections often occur when bacteria 'shut down', making antibiotics ineffective against them, reports the journal Nature . Over time, the bugs, known as 'persisters', return to life, causing patients to relapse, according to the Daily Mail . Boston University scientists tested the effects of drawing the bacteria out of their hibernation using sugar. They found stimulating the bugs with sugar renders them vulnerable to antibiotic attack. Testing the strategy on Eschericia coli (E. coli) bacteria, a common cause of urinary infections, the researchers were able to eliminate 99.9 per cent of persisters in just two hours. Without sugar, the drugs they used had no effect. The team now plans to examine whether sugar additives can help fight tuberculosis