Helicobacter pylori is a bacterium commonly found in the human digestive tract, often linked to stomach ulcers. New research suggests that the pathogen is attracted to bleach.
50% of all human are believed to have Helicobacter pylori present in their stomachs. While most people do not show symptoms, this bacterium can cause gastritis, ulcers and if left untreated, it can lead to stomach cancers.
Pre-existing research has shown that a Helicobacter pylori protein known as transducer-like protein D (TlpD) is required for the bacterium to efficiently populate the stomach.
A new study led by Arden Perkins and a team of researchers from the University of Oregon in Eugene, USA, hypothesises that TlpD might respond to hypochlorous acid (HOCI), commonly known as bleach.
If inflamed, certain cells naturally produce bleach as an antimicrobial defence. However, microbes like Helicobacter pylori strategically navigate to these inflamed areas.
Following research, Arden Perkins and team found that bleach causes a specific change in the molecular shape of TlpD. The changes appear to serve as a signal that is transmitted to other proteins involved in Helicobacter pylori navigation.
The research also suggests that bleach-sensing by TlpD enables the Helicobacter pylori to utilise the body’s defences to seek out inflamed damaged stomach tissue.
The research article states: “The gastric pathogen Helicobacter pylori requires a noncanonical cytosolic chemoreceptor transducer-like protein D (TlpD) for efficient colonization of the mammalian stomach. Here, we reconstituted a complete chemotransduction signaling complex in vitro with TlpD and the chemotaxis (Che) proteins CheW and CheA, enabling quantitative assays for potential chemotaxis ligands.
“We found that TlpD is selectively sensitive at micromolar concentrations to bleach (hypochlorous acid, HOCl), a potent antimicrobial produced by neutrophil myeloperoxidase during inflammation. HOCl acts as a chemoattractant by reversibly oxidizing a conserved cysteine within a 3His/1Cys Zn-binding motif in TlpD that inactivates the chemotransduction signaling complex.”