Peptide Extracts from Cultures of Certain Lactobacilli Inhibit Helicobacter pylori
Luc De Vuyst1, Pascal Vincent2,3, Eleftherios Makras4
1Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium. ldvuyst@vub.ac.be.
Probiotics and Antimicrobial Proteins
|January 20, 2016
Summary
Certain probiotic lactobacilli, specifically Lactobacillus amylovorus and Lactobacillus johnsonii, produce peptide extracts that effectively inhibit Helicobacter pylori growth. These findings suggest a potential mechanism for probiotics in H. pylori eradication therapies.
Area of Science:
- Microbiology
- Probiotics
- Gastrointestinal Health
Background:
- Probiotic lactobacilli demonstrate inhibitory effects against Helicobacter pylori.
- The precise mechanisms behind this inhibition remain largely unelucidated.
- Understanding these mechanisms is crucial for developing novel H. pylori eradication strategies.
Purpose of the Study:
- To investigate the role of peptide extracts from specific Lactobacillus strains in inhibiting H. pylori.
- To identify which Lactobacillus species produce the most potent antibacterial peptides against H. pylori.
- To confirm the proteinaceous nature of the inhibitory compounds.
Main Methods:
- Preparation of peptide extracts from six Lactobacillus cultures: L. acidophilus La1, L. amylovorus DCE 471, L. casei YIT 9029, L. gasseri K7, L. johnsonii La1, and L. rhamnosus GG.
- Assessing the inhibitory activity of these extracts against H. pylori ATCC 43504 by measuring viability reduction.
- Testing the susceptibility of six clinical H. pylori isolates to the active peptide extracts.
- Evaluating the effect of protease treatment on the inhibitory activity of the peptide extracts.
Main Results:
- Peptide extracts from L. amylovorus DCE 471 and L. johnsonii La1 significantly reduced H. pylori viability by over 2 log units within 4 hours.
- Four other tested Lactobacillus extracts showed minimal or no inhibitory activity.
- Similar potent inhibition was observed with L. amylovorus DCE 471 and L. johnsonii La1 extracts against six clinical H. pylori isolates.
- Protease treatment rendered the extracts inactive, confirming the inhibitory substances are proteinaceous.
Conclusions:
- Peptide extracts from Lactobacillus amylovorus DCE 471 and Lactobacillus johnsonii La1 possess significant antibacterial activity against Helicobacter pylori.
- These findings highlight bacteriocins or other antibacterial peptides produced by specific lactobacilli as key components in H. pylori inhibition.
- The study supports the potential of selected probiotic strains and their derived peptides in therapeutic strategies for H. pylori infection.
More Related Videos
Related Concept Videos
01:16Treating Helicobacter pylori in Peptic Ulcers: Antimicrobial Therapy
2.0K
Helicobacter pylori, a resilient gram-negative bacterium, can thrive in the stomach's harsh, acidic environment. Infection with H. pylori leads to a cascade of events within the stomach lining. One of the critical disruptions caused by this bacterium is the interference with somatostatin production, a hormone responsible for regulating acid secretion. This interference tips the balance, escalating acid secretion and diminishing bicarbonate levels. This imbalance compromises the defensive...
2.0K
01:23Inhibitors of Gram-positive Cell Wall Synthesis
33
Bacterial cell walls are typically rigid structures composed mainly of peptidoglycan, a mesh-like polymer that provides mechanical strength and maintains cell shape. The synthesis of peptidoglycan is a crucial process in bacterial growth and serves as a primary target for many antibiotics.Mechanism of Action of Beta-Lactam AntibioticsBeta-lactam antibiotics, such as penicillin, inhibit peptidoglycan synthesis in actively growing cells. These antibiotics share a characteristic four-membered...
33
01:13Acid Suppressive Drugs for Peptic Ulcer Disease: Proton Pump Inhibitors
1.2K
Peptic ulcers, often induced by H. pylori infections or NSAID usage, arise from disruptions in the delicate balance of gastric acid production. Peptic ulcers stem from heightened gastric acid levels due to H. pylori infections or NSAID use. The protective mucus layer diminishes in the presence of these factors, allowing gastric acid to erode the stomach lining and form ulcers.
Gastric acid, a potent cocktail of hydrogen and chloride ions, is produced in specialized parietal cells within the...
Gastric acid, a potent cocktail of hydrogen and chloride ions, is produced in specialized parietal cells within the...
1.2K
01:28Acid Suppressive Drugs for Peptic Ulcer Disease: Histamine H2-Receptor Antagonists
1.2K
Histamine H2 receptors, which are intricately located on the basolateral membrane of parietal cells, play a crucial role in modulating gastric acid secretion. When released from enterochromaffin-like cells, histamine engages H2 receptors, initiating the cyclic AMP (cAMP) pathway. In this pathway, adenylyl cyclase converts ATP into cAMP, elevating intracellular cAMP levels. The activation of protein kinase A follows, stimulating the proton pump. This stimulation prompts the secretion of hydrogen...
1.2K
01:27Peptic Ulcer
27
Peptic ulcers are erosive lesions of the gastric or duodenal lining, most commonly caused by Helicobacter pylori infection. This Gram-negative, helical bacterium has adapted to survive the stomach’s acidic environment by producing urease, which converts urea into ammonia and carbon dioxide. The ammonia neutralizes gastric acid in the bacterium’s immediate environment, allowing colonization of the gastric mucosa. H. pylori attaches to mucus-secreting epithelial cells, penetrates the...
27
01:23Antimicrobial Proteins
15.3K
Antimicrobial proteins are important components of the immune system. They aid the body in combating pathogens by either killing them directly or hindering their replication processes. Four main types of antimicrobial substances are interferons, the complement system, iron-binding proteins, and antimicrobial proteins.
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
15.3K