- Helicobacter saguini is a Gram-negative, microaerophilic, spiral-shaped bacterium within the Helicobacter genus.
- It was first isolated from the intestines and feces of cotton-top tamarins (Saguinus oedipus), a small primate species.
- This bacterium is classified as an enterohepatic Helicobacter species (EHS), meaning it primarily colonizes the intestines and hepatobiliary systems of its hosts.
- Its discovery has expanded the understanding of Helicobacter species diversity and their association with non-human primates.
Morphology and Characteristics
- H. saguini exhibits several defining features typical of the Helicobacter genus.
- The bacterium is fusiform and motile, possessing flagella that aid in its movement through mucus layers.
- It is Gram-negative, characterized by a thin peptidoglycan layer and an outer membrane.
- As a microaerophilic organism, H. saguini thrives in environments with reduced oxygen levels, such as the gastrointestinal tract.
- It is urease-negative, distinguishing it from urease-positive Helicobacter species like H. pylori. Additionally, it produces proinflammatory cytokines, which may contribute to its pathogenic potential.
Isolation and Host Association
- The initial isolation of H. saguini occurred during studies of cotton-top tamarins with chronic colitis.
- The bacterium was detected in a significant proportion of fecal and intestinal samples from tamarins, suggesting a specific ecological relationship with this host species.
- Its presence in tamarins highlights its potential role in gastrointestinal health and disease in non-human primates.
Taxonomy and Nomenclature
- The species name “saguini” reflects its origin from cotton-top tamarins, as “Saguinus” is the taxonomic genus name of its host. Genetic and phenotypic analyses confirmed its classification as a distinct species within the Helicobacter genus.
- The type strain of H. saguini is designated as MIT 97-6194-5, providing a reference for future studies.
Pathogenic Potential and Research Relevance
- H. saguini has been associated with chronic colitis in cotton-top tamarins, a condition characterized by inflammation, epithelial defects, and mucosal hyperplasia.
- Experimental studies using gnotobiotic IL-10-deficient mice have shown that H. saguini can induce typhlocolitis, dysplasia, and proinflammatory cytokine production.
- These findings suggest that H. saguini may serve as a valuable model organism for studying inflammatory bowel disease (IBD) and colorectal cancer.
Public Health and Research Implications
- The discovery of H. saguini underscores the importance of studying Helicobacter species in non-human primates.
- While there is no evidence to suggest zoonotic transmission or human health implications, monitoring Helicobacter species in research animals is essential for understanding their ecological roles and potential risks.
- Research into H. saguini may provide insights into the broader Helicobacter genus and its role in gastrointestinal health and disease.
