Lactiplantibacillusplantarum APsulloc331261 (GTB1™) promotes butyrate production to suppress mucin hypersecretion in a murine allergic airway inflammation model

IntroductionAllergic airway diseases are one of the serious health problems in worldwide and allergic airway inflammation is a prerequisite led to the exacerbated situation such as mucus hypersecretion, epithelial barrier damage and microbiota dysbiosis. Because of side effects and low efficiencies of current therapeutics, the need for novel alternatives has been urged. Probiotics in which have diverse and beneficial modulatory effects have been applied to the airway inflammation model and the underlying mechanism needs to be investigated.MethodsWe aimed to evaluate whether our target strain, Lactiplantibacillus plantarum APsulloc331261 (GTB1TM) isolated from green tea, can ameliorate allergic airway inflammation in mice and to figure out the mechanism. We induced allergic airway inflammation to mice by ovalbumin (OVA) and administered GTB1 orally and the immune and epithelial barrier markers were assessed. The gut metabolite and microbiota were also analysed, and the in vitro cell-line experiment was introduced to confirm the hypothesis of the study.ResultsGTB1 ameliorated type 2 inflammation and suppressed mucin hypersecretion with the inhibition of MUC5AC in inflamed mice. Moreover, GTB1 increased the butyrate production and the relative abundance of butyrate producer, Clostridium cluster IV. We assumed that butyrate may have a potential role and investigated the effect of butyrate in mucin regulation via human airway epithelial cell line, A549. Butyrate significantly reduced the gene expression of MUC5AC in A549 cells suggesting its regulatory role in mucus production.ConclusionTherefore, our study demonstrates that the oral administration of GTB1 can ameliorate allergic airway inflammation and mucin hypersecretion by butyrate production

International Committee on Systematics of Prokaryotes Subcommittee on the Taxonomy of Bifidobacterium, Lactobacillus and related organisms. Minutes of the closed meeting by videoconference, 3 September 2020

International Committee on Systematics of Prokaryotes Subcommittee on the Taxonomy of Bifidobacterium, Lactobacillus and related organisms. Minutes of the closed meeting by videoconference, 3 September 202

Lactobacillus curvatus subsp. melibiosus is a later synonym of Lactobacillus sakei subsp. carnosus

On the basis of phenotypic and DNA-DNA reassociation studies, strain CCUG 34545T has been considered to represent a distinct Lactobacillus curvatus subspecies, Lactobacillus curvatus subsp. melibiosus. However, in several independent studies dealing with Lactobacillus sakei and L. curvatus strains, the subspecies division of L. curvatus has been found to be controversial. The original study distinguishing the two subspecies within both L. curvatus and L. sakei also lacked 16S rRNA gene sequence analyses. Therefore, the taxonomic position of L. curvatus subsp. melibiosus CCUG 34545T was re-evaluated in a polyphasic taxonomy study that included 16S rRNA gene sequence analysis, DNA-DNA reassociation, DNA G+C content deternmination, numerical analysis of ribotypes and whole-cell protein patterns and the examination of some fundamental phenotypic properties. The results obtained indicate that strain CCUG 34545T and its duplicate, CCUG 41580T, are Lactobacillus sakei subsp. carnosus strains and that L. curvatus subsp. melibiosus is a later synonym of L. sakei subsp. carnosus

Autoinducer-2 Quorum Sensing Influences Viability of Escherichia coli O157:H7 under Osmotic and In Vitro Gastrointestinal Stress Conditions

Bacteria use autoinducer molecules to communicate both at intra-species and inter-species levels by quorum sensing. One such cell density-dependent signaling system is the luxS-mediated universal quorum sensing using autoinducer-2 (AI-2). Virulence of several pathogens is determined by an AI-2 system and is related to colonization and infection of the host. From this concept, numerous papers have suggested that AI-2 inhibition is an important strategy toward designing of new antimicrobial agents. However, recent studies indicate that the AI-2 system is also involved in adaptation and survival under environmental stress conditions. Therefore, we hypothesized that interaction between quorum sensing and environmental conditions may be critical in influencing predicted results in a control and when combating of target pathogens. We investigated the growth of enterohemorrhagic Escherichia coli O157:H7 (EHEC) and its luxS-deficient (non AI-2 producing) mutant strain under various stress conditions, and found significant differences in the growth rate under osmotic stress. Moreover, we could also show the impact of the AI-2 molecule on viability in the gastrointestinal tract model representing a complex environmental condition. Differences in vital responses of the strains suggest that AI-2 quorum sensing has a significant influence on the viability of EHEC under environmental stress conditions

Dose-dependent and strain-dependent anti-obesity effects of Lactobacillus sakei in a diet induced obese murine model

Background Overweight and abdominal obesity, in addition to medical conditions such as high blood pressure, high blood sugar and triglyceride levels, are typical risk factors associated with metabolic syndrome. Yet, considering the complexity of factors and underlying mechanisms leading to these inflammatory conditions, a deeper understanding of this area is still lacking. Some probiotics have a reputation of a relatively-long history of safe use, and an increasing number of studies are confirming benefits including anti-obesity effects when administered in adequate amounts. Recent reports demonstrate that probiotic functions may widely differ with reference to either intra-species or inter-species related data. Such differences do not necessarily reflect or explain strain-specific functions of a probiotic, and thus require further assessment at the intra-species level. Various anti-obesity clinical trials with probiotics have shown discrepant results and require additional consolidated studies in order to clarify the correct dose of application for reliable and constant efficacy over a long period. Methods Three different strains of Lactobacillus sakei were administered in a high-fat diet induced obese murine model using three different doses, 1 × 1010, 1 × 109 and 1 × 108 CFUs, respectively, per day. Changes in body and organ weight were monitored, and serum chemistry analysis was performed for monitoring obesity associated biomarkers. Results Only one strain of L. sakei (CJLS03) induced a dose-dependent anti-obesity effect, while no correlation with either dose or body or adipose tissue weight loss could be detected for the other two L. sakei strains (L338 and L446). The body weight reduction primarily correlated with adipose tissue and obesity-associated serum biomarkers such as triglycerides and aspartate transaminase. Discussion This study shows intraspecies diversity of L. sakei and suggests that anti-obesity effects of probiotics may vary in a strain- and dose-specific manner

Taxonomic study of Weissella confusa and description of Weissella cibaria sp. nov., detected in food and clinical samples

http://ijs.sgmjournals.org/A taxonomic study was conducted in order to clarify the relationships of two bacterial populations belonging to the genus Weissella. A total of 39 strains originating mainly from Malaysian foods (22 strains) and clinical samples from humans (9 strains) and animals (6 strains) were analysed using a polyphasic taxonomic approach. The methods included classical phenotyping, whole-cell protein electrophoresis, 16S and 23S rDNA RFLP (ribotyping), the determination of 16S rDNA sequence homologies, and DNA-DNA reassociation levels. Based on the results, the strains were considered to represent two different species, Weissella confusa and a novel Weissella species, for which we propose the name Weissella cibaria sp. nov. W. confusa possessed the highest 16S rDNA sequence similarity to W. cibaria sp. nov. but the DNA-DNA reassociation experiment showed hybridisation levels below 49% between the strains studied. The numerical analyses of W. confusa and W. cibaria sp. nov. strains did not reveal any specific clustering with respect to the origin of the strains. Based on whole cell protein electrophoresis, ClaI and HindIII ribotyping patterns, food and clinical isolates were randomly located in the two species-specific clusters obtained

The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on fermented foods

An expert panel was convened in September 2019 by The International Scientific Association for Probiotics and Prebiotics (ISAPP) to develop a definition for fermented foods and to describe their role in the human diet. Although these foods have been consumed for thousands of years, they are receiving increased attention among biologists, nutritionists, technologists, clinicians and consumers. Despite this interest, inconsistencies related to the use of the term ‘fermented’ led the panel to define fermented foods and beverages as “foods made through desired microbial growth and enzymatic conversions of food components”. This definition, encompassing the many varieties of fermented foods, is intended to clarify what is (and is not) a fermented food. The distinction between fermented foods and probiotics is further clarified. The panel also addressed the current state of knowledge on the safety, risks and health benefits, including an assessment of the nutritional attributes and a mechanistic rationale for how fermented foods could improve gastrointestinal and general health. The latest advancements in our understanding of the microbial ecology and systems biology of these foods were discussed. Finally, the panel reviewed how fermented foods are regulated and discussed efforts to include them as a separate category in national dietary guidelines

The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on fermented foods

An expert panel was convened in September 2019 by The International Scientific Association for Probiotics and Prebiotics (ISAPP) to develop a definition for fermented foods and to describe their role in the human diet. Although these foods have been consumed for thousands of years, they are receiving increased attention among biologists, nutritionists, technologists, clinicians and consumers. Despite this interest, inconsistencies related to the use of the term ‘fermented’ led the panel to define fermented foods and beverages as “foods made through desired microbial growth and enzymatic conversions of food components”. This definition, encompassing the many varieties of fermented foods, is intended to clarify what is (and is not) a fermented food. The distinction between fermented foods and probiotics is further clarified. The panel also addressed the current state of knowledge on the safety, risks and health benefits, including an assessment of the nutritional attributes and a mechanistic rationale for how fermented foods could improve gastrointestinal and general health. The latest advancements in our understanding of the microbial ecology and systems biology of these foods were discussed. Finally, the panel reviewed how fermented foods are regulated and discussed efforts to include them as a separate category in national dietary guidelines

Characterization of Leuconostoc gasicomitatum sp. nov., Associated with Spoiled Raw Tomato-Marinated Broiler Meat Strips Packaged under Modified-Atmosphere Conditions

http://aem.asm.org/Lactic acid bacteria (LAB) associated with gaseous spoilage of modified-atmosphere-packaged, raw, tomatomarinated broiler meat strips were identified on the basis of a restriction fragment length polymorphism (RFLP) (ribotyping) database containing DNAs coding for 16S and 23S rRNAs (rDNAs). A mixed LAB population dominated by a Leuconostoc species resembling Leuconostoc gelidum caused the spoilage of the product. Lactobacillus sakei, Lactobacillus curvatus, and a gram-positive rod phenotypically similar to heterofermentative Lactobacillus species were the other main organisms detected. An increase in pH together with the extreme bulging of packages suggested a rare LAB spoilage type called “protein swell.” This spoilage is characterized by excessive production of gas due to amino acid decarboxylation, and the rise in pH is attributed to the subsequent deamination of amino acids. Protein swell has not previously been associated with any kind of meat product. A polyphasic approach, including classical phenotyping, whole-cell protein electrophoresis, 16 and 23S rDNA RFLP, 16S rDNA sequence analysis, and DNA-DNA reassociation analysis, was used for the identification of the dominant Leuconostoc species. In addition to the RFLP analysis, phenotyping, whole-cell protein analysis, and 16S rDNA sequence homology indicated that L. gelidum was most similar to the spoilage-associated species. The two spoilage strains studied possessed 98.8 and 99.0% 16S rDNA sequence homology with the L. gelidum type strain. DNA-DNA reassociation, however, clearly distinguished the two species. The same strains showed only 22 and 34% hybridization with the L. gelidum type strain. These results warrant a separate species status, and we propose the name Leuconostoc gasicomitatum sp. nov. for this spoilage-associated Leuconostoc species