Cryo-EM structure of Helicobacter pylori urease with a novel inhibitor in the active site at 2.0 A resolution

Abstract

Infection of the human stomach by Helicobacter pylori remains a worldwide problem and greatly contributes to peptic ulcer disease and gastric cancer. Without active intervention approximately 50% of the world population will continue to be infected with this gastric pathogen. Current eradication, called triple therapy, entails a proton-pump inhibitor and two broadband antibiotics, however resistance to either clarithromycin or metronidazole is greater than 25% and rising. Therefore, there is an urgent need for a targeted, high-specificity eradication drug. Gastric infection by H. pylori depends on the expression of a nickeldependent urease in the cytoplasm of the bacteria. Here, we report the 2.01 [A] resolution structure of the 1.1 MDa urease in complex with a novel inhibitor by cryo-electron microscopy and compare it to a {beta}-mercaptoethanol-inhibited structure at 2.45 [A] resolution. The structural information is of sufficient detail to aid in the development of inhibitors with high specificity and affinity.