Three Tests Used to Identify Non-Culturable Form of Helicobacter pylori in Water Samples

Oral Microbiota, a Potential Determinant for the Treatment Efficacy of Gastric Helicobacter pylori Eradication in Humans

The oral cavity serves as another reservoir for gastric Helicobacter pylori and may contribute to the failure of gastric H. pylori eradication therapy. However, changes to the oral microbial composition after gastric H. pylori eradication therapy has not yet been identified. This study aims to dissect whether the oral microbiota is involved and which bacterium mediates the clinic failure in H. pylori eradication. In the present study, the oral microorganisms from patients who had received the gastric H. pylori eradication treatment were analyzed by a high-throughput 16S rRNA deep sequencing. We found that the β diversity and composition of oral microbiota were remarkably changed in the patients who had experienced successful gastric H. pylori eradication treatment (SE group) compared to the failure group (FE group). Significantly enriched families, including Prevotellaceae, Streptococcaceae, Caulobacteraceae, and Lactobacillaceae, were detected in the SE group. In contrast, the bacterial families, such as Weeksellaceae, Neisseriaceae, Peptostreptococcaceae, Spirochaetaceae, and Veillonellaceae, were abundantly expressed in the FE group. Five operational taxonomic units (OTUs) were positively correlated with DOB values, while two OTUs exhibited negative trends. These different enriched OTUs were extensively involved in the 20 metabolic pathways. These results suggest that a balanced environment in the oral microbiota contributes to H. pylori eradication and metabolic homeostasis in humans. Our data demonstrated that the changes in oral microbiota might contribute to the therapeutic effects of antibiotic therapy. Therefore, a different therapy on the detrimental oral microbiota will increase the therapeutic efficacy of antibiotics on H. pylori infection.

Research progress in the Helicobacter pylori with viable non-culturable state

Helicobacter pylori (H. pylori) is one of the most common pathogens in human beings and it is responsible for diseases such as chronic gastritis, peptic ulcer, and even gastric cancer. Studies in recent years have found that H. Pylori could transform from the normal spiral-shaped bacillary form into the coccoid form and enter a viable but non-culturable (VBNC) state, which may pose a potential threat to public health. In this state,the morphological structure and physiological characteristics of H. Pylori have changed. It can maintain the metabolic activity but protein expression is decreased. And the H. Pylori in this state cannot grow in the culture medium. Conditions such as environmental factors, antibiotics, and inhibitors can induce H. Pylori to enter the VBNC state, but it is still not known whether H. pylori in the VBNC state can reactivate or not. Based on the cell membrane integrity and metabolic activity of H. pylori in the VBNC state, it can be detected by classical methods including direct microscopy of live bacteria and molecular biological methods such as reverse transcription-polymerase chain reaction. H. pylori in the VBNC state has been detected in water source and biological media. It has been also found that H. pylori can enter the VBNC state in artificially contaminated food, which poses challenges to public health and food safety. Therefore, it is of great significance to study the change pattern and detection methods of H. pylori in the VBNC state for the prevention and control of H. pylori in the VBNC state. It is valuable to further study the underlying mechanisms of H. pylori in the VBNC state.

Loop-Mediated Isothermal Amplification (LAMP) Assay for Rapid Detection of viable but non-culturable Vibrio cholerae O1

Vibrio cholerae, an important waterborne pathogen, is a rod-shaped bacterium that naturally exists in aquatic environments. When conditions are unfavorable for growth, the bacterium can undergo morphological and physiological changes to assume a coccoid morphology. This stage in its life cycle is referred to as viable but non-culturable (VBNC) since VBNC cells do not grow on conventional bacteriological culture media. The current study compared polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) to detect and identify VBNC V. cholerae. Because it is difficult to detect and identify VBNC V. cholerae, the results of the current study are useful in showing LAMP to be more sensitive and rapid than PCR in detecting and identifying non-culturable, coccoid forms of V. cholerae. Furthermore, the LAMP method is effective in detecting and identifying very low numbers of coccoid VBNC V. cholerae in environmental water samples, with the added benefit of being inexpensive to perform.

Colonization of Helicobacter pylori in the oral cavity - an endless controversy?

Helicobacter pylori is associated with chronic gastritis, gastric or duodenal ulcers, and gastric cancer. Since the oral cavity is the entry port and the first component of the gastrointestinal system, the oral cavity has been discussed as a potential reservoir of H. pylori. Accordingly, a potential oral-oral transmission route of H. pylori raises the question concerning whether close contact such as kissing or sharing a meal can cause the transmission of H. pylori. Therefore, this topic has been investigated in many studies, applying different techniques for detection of H. pylori from oral samples, i.e. molecular techniques, immunological or biochemical methods and traditional culture techniques. While molecular, immunological or biochemical methods usually yield high detection rates, there is no definitive evidence that H. pylori has ever been isolated from the oral cavity. The specificity of those methods may be limited due to potential cross-reactivity, especially with H. pylori-like microorganisms such as Campylobacter spp. Furthermore, the influence of gastroesophageal reflux has not been investigated so far. This review aims to summarize and critically discuss previous studies investigating the potential colonization of H. pylori in the oral cavity and suggest novel research directions for targeting this critical research question.

Methods for Detecting the Environmental Coccoid Form of Helicobacter pylori

Helicobacter pylori is recognized as the most common pathogen to cause gastritis, peptic and duodenal ulcers, and gastric cancer. The organisms are found in two forms: (1) spiral-shaped bacillus and (2) coccoid. H. pylori coccoid form, generally found in the environment, is the transformed form of the normal spiral-shaped bacillus after exposed to water or adverse environmental conditions such as exposure to sub-inhibitory concentrations of antimicrobial agents. The putative infectious capability and the viability of H. pylori under environmental conditions are controversial. This disagreement is partially due to the fact of lack in detecting the coccoid form of H. pylori in the environment. Accurate and effective detection methods of H. pylori will lead to rapid treatment and disinfection, and less human health damages and reduction in health care costs. In this review, we provide a brief introduction to H. pylori environmental coccoid forms, their transmission, and detection methods. We further discuss the use of these detection methods including their accuracy and efficiency.