She studies protein-making machinery of bacteria for next-generation antibiotics

Israeli scientist Ada Yonath has been called "the world's dreamer". PHOTO: NATIONAL RESEARCH FOUNDATION

Some antibiotics are no longer packing a punch in getting rid of certain strains of bacteria, and global health authorities are concerned.

The World Health Organisation (WHO) has warned that the world is headed toward a post-antibiotic era if action is not taken to combat the issue of antibiotic resistance.

But one scientist is looking to prevent this by designing the "next generation of antibiotics".

"The increasing appearance of multi drug-resistant strains of bacteria, together with the negligible number of new antibiotic drugs that are presently undergoing development, is becoming a colossal health threat," Israeli scientist Ada Yonath, 81, told The Straits Times in an e-mail interview last week.

She added: "It seems that we will soon revert to the pre-antibiotic era, during which diseases caused by parasites or by simple or severe infections such as pneumonia or wounds were almost untreatable and resulted in frequent deaths."

Professor Yonath won a Nobel Prize in Chemistry in 2009 for her work in studying the structure and functions of the ribosome - becoming the first woman in 45 years to win this coveted prize.

She will be speaking virtually to young researchers about her research during the upcoming Global Young Scientists Summit this week.

Organised by the National Research Foundation, the summit gives young researchers worldwide a chance to interact with eminent scientists and technology leaders.

Prof Yonath, the director of the Helen and Milton A. Kimmelman Center for Biomolecular Structure and Assembly at the Weizmann Institute of Science, said her team's concept for fighting antibiotic resistance is designing the next generation of antibiotics by zooming into ribosomal structures in bacteria.

The ribosome is a protein-making machine in almost all living cells, that strings together molecules called amino acids to form long chains that will eventually become proteins.

Proteins in turn carry out many functions that are essential for life.

Many antibiotics combat bacterial infections by preventing bacterial ribosomes from working.

But most antibiotics target ribosomes in a broad range of bacteria, which act on non-target bacteria along with the targeted bacteria, and can lead to more antibiotic-resistant bacteria strains.

Broad-range antibiotics can also cause disruption to native bacteria in the body - akin to throwing the baby out with the bathwater.

Prof Yonath said such antibiotics rely on "traditional antibiotic binding sites" on bacterial ribosomes.

So to develop the next-generation antibiotics, it was key to map out the structure of ribosomes of disease-causing bacteria so as to identify new potential areas for antibiotics to target.

This leads to the next step of designing compounds that match these targets, "thus blocking their function, and eventually killing the pathogen," said Prof Yonath.

These antibiotics targeting ribosomes specific to disease-causing bacteria species are called narrow-spectrum antibiotics.

Prof Yonath had made about 25,000 attempts to crystallise bacterial ribosomes to study their structure before she and her team at the Weizmann Institute of Science in Israel finally succeeded in the 1980s. The international scientific community had tried and failed many times to crystallise ribosomes in the 1970s.

For her attempts, Prof Yonath has been called "the world's dreamer". This, she says, is driven by an inquiring mind she developed since her childhood.

"I was always very curious," she said, citing how she had tried to measure the height of her balcony when she was five.

"In order to reach the ceiling, I put a chair on the table. Then I fell to the ground floor and broke my arm," she shared.

This curiosity, and passion for science, is something she hopes young scientists will learn from.

She added: "My advice is: don't look for advice. Go after your curiosity."

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