New Superbug-Fighting Antibiotics Found In Human Breast Milk

Breast feeding is beneficial for both the mother and child. It is protective against many illnesses like ear infections, respiratory ailments, allergies, intestinal disorders, viruses, diabetes, childhood cancers, arthritis, pneumonia and many more. Mother's milk, which consists of a complex and continually changing blend of proteins, fats and sugars, helps protect babies against bacterial infections. In the past, scientists have concentrated their search for the source of its antibacterial properties on the proteins it contains. An interdisciplinary team of chemists and doctors at Vanderbilt University have found a new class of antibiotic hiding in plain sight: human breast milk.

Study director Steven Townsend said "This is the first example of generalized, antimicrobial activity on the part of the carbohydrates in human milk." "One of the remarkable properties of these compounds is that they are clearly non-toxic, unlike most antibiotics."

The basic motivation for the research was the growing problem of bacterial resistance to antibiotics, which the Center for Disease Control and Prevention estimates causes 23,000 deaths annually.

Townsend also said "We started to look for different methods to defeat infectious bacteria. For inspiration, we turned to one particular bacteria, Group B Strep. We wondered whether its common host, pregnant women, produces compounds that can either weaken or kill strep, which is a leading cause of infections in newborns worldwide".

Instead of searching for proteins in mother's milk with antimicrobial properties, Townsend and his colleagues turned their attention towards the sugars, which are considerably more difficult to study.

Townsend added "For most of the last century, biochemists have argued that proteins are most important and sugars are an afterthought. Most people have bought into that argument, even though there's no data to support it".

He further added "Far less is known about the function of sugars and, as a trained glycoprotein chemist, I wanted to explore their role."

To test the antibacterial properties of the sugars, the team first extracted compounds called oligosaccharides from a few different samples of human breast milk. Using mass spectrometry, they created profiles of the compounds, and then introduced them to cultures of infectious bacteria - in this case, Group B Strep, a common culprit of infections in newborns.

Townsend said "Our results show that these sugars have a one-two punch." He added "First, they sensitize the target bacteria and then they kill them. Biologists sometimes call this 'synthetic lethality' and there is a major push to develop new antimicrobial drugs with this capability."

The study is published in the ACS Infectious Diseases journal.

With inputs from ANI

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