Scientists in the United States have made a big breakthrough in understanding how a dangerous toxin produced by gut bacteria may cause colon cancer. The study was published in the journal Science.
This toxin, called colibactin, is made by certain strains of E. coli and other microbes that naturally live in the human gut. Although scientists have known about colibactin for years, they have struggled to study it because it breaks down very quickly.
Colibactin is a powerful substance that attacks the DNA inside our cells. DNA is like the instruction manual for how our cells work, grow, and repair themselves. When DNA is damaged, especially in a way that isn’t properly fixed, it can lead to cancer.
In this study, the scientists used advanced tools like mass spectrometry and nuclear magnetic resonance spectroscopy to study colibactin at the atomic level.
The researchers found that colibactin doesn’t damage DNA randomly. It goes after specific parts of the DNA that are rich in two types of building blocks—adenine and thymine. These regions are attractive to colibactin because of the way the molecule is shaped and charged.
It forms a strong bond between the two strands of DNA, a kind of glue-like link known as an interstrand cross-link, or ICL. This is a very serious form of damage because it locks the two DNA strands together, stopping the cell from copi…
They also discovered that the toxin attacks a particular part of the DNA structure called the minor groove. This is a narrow channel in the DNA helix where the two backbones of the DNA come close together.
The core of the colibactin molecule is unstable and positively charged, which is drawn to the negatively charged minor groove. This “lock and key” fit helps colibactin find the right spot to attach and do damage.
This new research gives scientists a clear picture of how colibactin works, right down to its chemical structure and how it interacts with human DNA. The researchers noted that this discovery is unlike anything previously seen with natural toxins.
It helps explain why doctors often see the same kinds of DNA mutations in patients with colorectal cancer. Now that the mechanism is known, scientists can start developing tools to detect the damage early and potentially stop it before it turns into cancer.
Understanding how colibactin causes damage opens up several new possibilities. For example, researchers might be able to create tests that screen people who have higher levels of colibactin-producing bacteria in their gut.
It might also be possible to design treatments that block the toxin from forming or prevent it from binding to DNA. Another exciting possibility is changing a person’s diet or gut bacteria to lower the levels of harmful bacteria that produce colibactin.
In conclusion, this study marks a major step forward in cancer research. It proves that some gut bacteria can directly damage our DNA in ways that lead to cancer.
By understanding how colibactin works, scientists are now better equipped to find ways to protect people from this threat. The future may bring better screening tools, new treatments, and lifestyle changes that reduce the risk of colorectal cancer.
If you care about cancer, please read studies that a low-carb diet could increase overall cancer risk, and vitamin D supplements could strongly reduce cancer death.
For more information about health, please see recent studies about how drinking milk affects the risks of heart disease and cancer and results showing higher intake of dairy foods linked to higher prostate cancer risk.
Copyright © 2025 Knowridge Science Report. All rights reserved.
