We all know that eating leafy green vegetables is good for our health in many ways, but if you needed more motivation, researchers have some for you. A study published today in the journal Nature Chemical Biology says that a special type of sulfur-containing sugar called sulfoquinovose (SQ for short) is able to help the body colonize “good” gut bacteria.
The finding suggests that leafy greens are able to limit the ability of bad bacteria to colonise the gut by shutting them out of the prime ‘real estate’. “Every time we eat leafy green vegetables we consume significant amounts of SQ sugars, which are used as an energy source by good gut bacteria,” says researcher Dr. Goddard-Borger.
“Bacteria in the gut, such as crucial protective strains of E. coli, use SQ as a source of energy. E. coli provides a protective barrier that prevents growth and colonisation by bad bacteria, because the good bugs are taking up all the habitable real estate,” he said said.
“E. coli is a key bacterial coloniser needed by our gut. We speculate that consumption of this specific molecule within leafy greens will prove to be an important factor in improving and maintaining healthy gut bacteria and good digestive health.”
Professor Williams said the team had revealed how bacteria extract the sugar from plants in order to fuel their growth. “We discovered the enzyme YihQ, which is used by bacteria to absorb and metabolise these sulfur-containing sugars as food,” he said.
“Sulfur is critical for building proteins, the essential components of all living organisms. SQ is the only sugar molecule which contains sulfur, and ‘digestion’ of the molecule by bacteria releases sulfur into the environment, where it re-enters the global ‘sulfur cycle’ to be reused by other organisms.”
Professor Williams said that the pathway was unusual, but abundant in biological organisms.
“This work answers a 50-year mystery that has surrounded how sulfur – an element essential for life on Earth – was used and recycled by living organisms,” he said. “What is remarkable is that the YihQ enzyme was hiding in plain sight and is produced by the humble bacterium E. coli, present in nearly every biologist’s laboratory.”
“We think it will be possible to use these widespread enzymes to enable highly specific delivery of antibiotics to harmful forms of E. coli and other pathogens, such as Salmonella, responsible for food poisoning, while leaving the good gut bacteria untouched.”