Pneumonia could hold the key to beating deadly superbugs

By Mark Waghorn via SWNS

Pneumonia could hold the key to beating deadly superbugs after scientists discovered it secretes a toxin that kills other bacteria.

The breakthrough opens the door to a generation of more effective antibiotics.

Untreatable infections will be claiming 10 million lives a year by 2050 unless more effective drugs are developed.

Pseudomonas aeruginosa is a pathogen that causes hospital-acquired infections - including pneumonia.

It contains a compound that has evolved to destroy other microbes - including species too strong for normal medicines.

And the crucial aspect is its mechanism, explained lead author Professor John Whitney.

"This research is significant, because it shows the toxin targets essential RNA molecules of other bacteria, effectively rendering them non-functional," he said.

"Like humans, bacteria require properly functioning RNA in order to live."

It has structural similarities to DNA - turning genetic information into proteins.

First author Nathan Bullen, a student in Whitney's lab, said: "It's a total assault on the cell because of how many essential pathways depend on functional RNAs.

"This toxin enters its target, hijacks an essential molecule needed for life, and then uses that molecule to disrupt normal processes."

They identified its three dimensional shape by examining crystals of the purified toxin under a state-of-the-art scanner at McMaster University.

The Canadian team have been working with colleagues at Imperial College London for nearly three years to understand exactly how the toxin functions at a molecular level.

Rigorous experimentation on common targets such as proteins and DNA molecules led to testing it against RNA.

The breakthrough shatters well-established precedents set by toxins secreted by other bacteria - such as those that cause cholera and diphtheria.

The study, published in the journal Molecular Cell, says it holds great potential for solving the infectious diseases crisis - described by the World Health Organization as "one of the biggest threats to mankind."

Currently they cause an estimated 700,000 deaths annually - a figure set to soar almost fifteenfold within three decades.

Over-prescribing, people not taking antibiotics properly and farmers feeding them to animals are all believed to have contributed to the medicines becoming weaker.

Part of the problem is the ability of bugs to evolve after exposure to small amounts of antibiotics. They learn how to survive attacks.

The new compound's 'mode' of activity can be exploited for future antibiotics as it kills bacteria in a different way, added Whitney.