Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Biological Chemistry

Decoding H. Pylori’s Gut-Wrenching Grip

Microbiome: Researchers uncover how the ulcer-causing bacterium attaches to the stomach lining of vulnerable people

by Sarah Everts
August 17, 2015 | A version of this story appeared in Volume 93, Issue 32

When Helicobacter pylori bacteria take up long-term residence in human stomachs, the persistent infection can cause ulcers and stomach cancer. A team of researchers led by Tina Howard at AstraZeneca and Franco H. Falcone at the University of Nottingham, in England, has now revealed how H. pylori maintains a tenacious hold in the human stomach (Sci. Adv. 2015, DOI: 10.1126/sciadv.1500315). The team obtained the 2-Å X-ray crystal structure of a protein called BabA found in H. pylori’s external membrane. The pathogen uses BabA to bind sugars found on epithelial cells that line the stomach wall. The team solved BabA’s structure in the presence of a six-sugar human bait found in individuals with O-type blood, who are particularly vulnerable to H. pylori infections. The team discovered that BabA, which is primarily an α-helical protein, has a β-strand domain that acts as the pathogen’s “hand.” Amino acids in the β-strand form hydrogen bonds with O-type blood sugars, grabbing onto them. The team hopes to find small molecules that interrupt these hydrogen bonds and consequently block H. pylori infections.

[+]Enlarge
Credit: Sci. Adv.
This BabA membrane protein helps ulcer-causing H. pylori bacteria clutch sugars (top right) attached to stomach wall cells.
This BabA protein helps Heliobacter pylori stick to human stomach walls.
Credit: Sci. Adv.
This BabA membrane protein helps ulcer-causing H. pylori bacteria clutch sugars (top right) attached to stomach wall cells.

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.