#dnaEdit: Game-changing antibiotic

The discovery of teixobactin, a potential ‘therapeutic candidate’ to kill ever-growing drug-resistant bacteria was described by the 21 researchers of diverse nationalities in their ‘breaking news’ article in the preeminent science journal, Nature, in its first weekly edition in the new year. It has triggered excitement as well as raised hopes in the medical circles. Antibiotics, which had turned out to be wonder drugs of the 20th century, starting with Alexander Fleming’s famous penicillin and anti-tubercular streptomycin in the 1940s, lost their magic and potency towards the end of the last century. Bacteria fought back by mutating and necessitated ever more powerful antibiotics. It has now been discovered that one of the reasons the resistance was growing, creating a panic because even ordinary infections did not respond to these tried-and-tested antibiotics, was that the laboratory-generated antibiotics have proved ineffective. Tuberculosis, which was once a killer disease till streptomycin was discovered, resurfaced and it drove patients and doctors to despair because it had evolved resistant strains. Teixobactin promises to break down drug-resistant TB.

It has also been argued that antibiotics became ineffective because of the over-prescription by the doctors. They were used to kill bacteria of every kind, and weakened the human immune system, the natural resistance of the body. It turned out that the protection offered was thin and when the bacterial infection returned in a mutated form, the drug was of no use. The doctors were blamed for the overuse of antibiotics, while research was not able to get at new antibiotic drugs at the same rate as the bacteria were evolving resistant strands. Patients, doctors and researchers seemed to have hit a dead end, and medical catastrophe stared in the face.

One of the exciting aspects of the discovery of teixobactin is that the scientists had gone back to the basics of identifying microbes in the soil that prey on other microbes. This was how Fleming discovered penicillin when he left the soil microbes in the Petri dish. In the decades that followed, researchers produced antibiotics from the very limited range of microbes that could be cultured in a laboratory. What the researchers have now done is to go back to the soil samples, and incubate them in the laboratory with the help of what has been described as a “multi-channel device, the iChip”. The scientists have conceded that 99 per cent of microbes in the soil cannot be cultured in a laboratory. So they found a way round it by recreating micro-soil chambers to let the microbes grow. Teixobactin is the result. 

It will be quite a few years before teixobactin will become available as a general use drug. It will take two years for human trials to be completed and another five years before it undergoes further multi-phased checks and enters the market. Scientists are happy because they see a new generation of super-antibiotics to beat the drug-immune superbugs. They have discovered the way back to the soil and the natural environment of microbes in contrast to the cultured microbes of the laboratories of the last several decades. The work on teixobactin has revealed that natural environment still holds the secrets of life on earth, and that soil-dwelling microbes have got greater vitality than lab-generated specimens. While stumbling upon a new drug and a new horizon in pharmaceuticals and therapeutic medicine, the researchers have reasserted if unwittingly an old principle. It is probable that the authors of this path-breaking research paper could be considered for the Nobel Prize in Physiology and Medicine this year.