Related Experiment Video
Updated: Feb 20, 2026
Non-Invasive Model of Neuropathogenic Escherichia coli Infection in the Neonatal Rat
Published on: October 29, 2014
Neisseria flavescens: A Urease-Expressing Potential Pathogen Isolated from Gastritis Patients
Bo Zeng1, Lijin Sun2, Yongmei Chen1
1Department of Pharmaceutical Engineering, Sichuan University of Science & Engineering, 180 Xueyuan Street, Zigong, 643000, Sichuan, China.
Abstract:
Parasitic pathogens, such as H. pylori (Helicobacter pylori), are considered as primary elements for causing stomach infection and leading to chronic gastritis or ulcers. Here, an unreported urease- and oxidase-producing Neisseria flavescens-like bacteria was isolated from the gastroscopic biopsies of 14C-UBT-positive gastritis patients. The isolate expressed the activity of urease, which is a pathogenic factor and considered as a reliable marker for diagnosis of H. pylori infection. However, the isolate didn't express the key functional genes of H. pylori including vacA and hpaA, and also the morphological feature of isolate was significantly different with H. pylori. Eventually, the 16S rDNA of isolate was sequenced and its sequence shared about 99.8% similarity with the N. flavescens standard strains, but about 20.8% similarity with the H. pylori. Further study of antibiotics-resistance revealed the N. flavescens isolate is high resistant to metronidazole, but highly sensitive to ampicillin sodium. To summarize, a urease-expressing N. flavescens strain was isolated and identified from Chinese gastritis patients; the encouraging results provides an important reference for the further study of its pathogenicity and the reasonable diagnosis and use of antibiotics clinically.
Insights
A urease-producing bacteria, identified as Neisseria flavescens, was isolated from gastritis patients. This finding offers insights into stomach infections and guides antibiotic use for Helicobacter pylori-like symptoms.
Area of Science:
- Microbiology
- Gastroenterology
- Infectious Diseases
Background:
- Helicobacter pylori is a primary cause of stomach infections, gastritis, and ulcers.
- Urease activity is a key pathogenic factor and diagnostic marker for H. pylori.
Purpose of the Study:
- To identify and characterize a novel urease-producing bacteria isolated from gastritis patients.
- To investigate the potential role of this isolate in stomach infections and its implications for diagnosis and treatment.
Main Methods:
- Isolation of bacteria from gastroscopic biopsies of 14C-UBT-positive gastritis patients.
- Biochemical assays for urease and oxidase production.
- Molecular identification using 16S rDNA sequencing.
- Antibiotic susceptibility testing.
Main Results:
- An unreported urease- and oxidase-producing Neisseria flavescens-like bacterium was isolated.
- The isolate lacked key H. pylori virulence genes (vacA, hpaA) and differed morphologically from H. pylori.
- 16S rDNA sequencing confirmed 99.8% similarity to N. flavescens and only 20.8% to H. pylori.
- The isolate showed high resistance to metronidazole and high sensitivity to ampicillin sodium.
Conclusions:
- A urease-expressing Neisseria flavescens strain was identified in Chinese gastritis patients.
- This finding provides a reference for studying its pathogenicity and for clinical diagnosis and antibiotic selection.
- Further research is warranted to understand the clinical significance of urease-producing N. flavescens.
Related Concept Videos
01:17Gastritis-II: Pathophysiology
In acute gastritis, the gastric mucosa becomes swollen and red and undergoes superficial erosion. Superficial ulceration may lead to bleeding.
In chronic gastritis, persistent or repeated insults lead to chronic inflammatory changes and, eventually, thinning or atrophy of the gastric tissue.
Gastritis can stem from various causes, each...
01:29Bacterial Flora of the Large Intestine
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
01:26Bacterial Phylum Bacteroidota