Effects of pickle brine and glycine addition on biogenic amine production in pickle fermentation.

This study investigated the effects of different pickle brines and glycine additions on biogenic amine formation in pickle fermentation. The results showed that the brines with higher biogenic amine content led to the production of more biogenic amines in the simulated pickle fermentation system. This was related to the abundance of biogenic amine-producing microorganisms in the microbial communities of the brines. Metagenome analysis of the brines and metatranscriptome analysis of the fermentation systems showed that putrescine was primarily from Lactobacillus, Oenococcus, and Pichia, while histamine and tyramine were primarily from Lactobacillus and Tetragenococcus. Addition of glycine significantly reduced the accumulation of biogenic amines in the simulated pickle fermentation system by as much as 70 %. The addition of glycine had no inhibitory effect on the amine-producing microorganisms, but it down-regulated the transcription levels of the genes for enzymes related to putrescine synthesis in Pichia, Lactobacillus, and Oenococcus, as well as the histidine decarboxylase genes in Lactobacillus and Tetragenococcus. Catalytic reaction assay using crude solutions of amino acid decarboxylase extracted from Lactobacillus brevis showed that the addition of glycine inhibited 45 %-55 % of ornithine decarboxylase and tyrosine decarboxylase activities. This study may provide a reference for the study and control of the mechanism of biogenic amine formation in pickle fermentation.

Comparative study of the gut microbial community structure of Spodoptera frugiperda and Spodoptera literal (Lepidoptera).

Background: Spodoptera frugiperda, the fall armyworm is a destructive invasive pest, and S. litura the tobacco cutworm, is a native species closely related to S. frugiperda. The gut microbiota plays a vital role in insect growth, development, metabolism and immune system. Research on the competition between invasive species and closely related native species has focused on differences in the adaptability of insects to the environment. Little is known about gut symbiotic microbe composition and its role in influencing competitive differences between these two insects. Methods: We used a culture-independent approach targeting the 16S rRNA gene of gut bacteria of 5th instar larvae of S. frugiperda and S. litura. Larvae were reared continuously on maize leaves for five generations. We analyzed the composition, abundance, diversity, and metabolic function of gut microbiomes of S. frugiperda and S. litura larvae. Results: Firmicutes, Proteobacteria, and Bacteroidetes were the dominant bacterial phyla in both species. Enterococcus, ZOR0006, Escherichia, Bacteroides, and Lactobacillus were the genera with the highest abundance in S. frugiperda. Enterococcus, Erysipelatoclostridium, ZOR0006, Enterobacter, and Bacteroides had the highest abundance in S. litura. According to α-diversity analysis, the gut bacterial diversity of S. frugiperda was significantly higher than that of S. litura. KEGG analysis showed 15 significant differences in metabolic pathways between S. frugiperda and S. litura gut bacteria, including transcription, cell growth and death, excretory system and circulatory system pathways. Conclusion: In the same habitat, the larvae of S. frugiperda and S. litura showed significant differences in gut bacterial diversity and community composition. Regarding the composition and function of gut bacteria, the invasive species S. frugiperda may have a competitive advantage over S. litura. This study provides a foundation for developing control strategies for S. frugiperda and S. litura.

The vaginal microbial signatures of preterm birth woman.

To explore the differences of vaginal microbes in women with preterm birth (PTB), and to construct prediction model. We searched for articles related to vaginal microbiology in preterm women and obtained four 16S rRNA-sequence datasets. We analyzed that for species diversity and differences, and constructed a random forest model with 20 differential genera. We introduce an independent whole genome-sequencing (WGS) data for validation. In addition, we collected vaginal and cervical swabs from 33 pregnant women who delivered spontaneously full-term and preterm infants, performed WGS in our lab to further validate the model. Compared to term birth (TB) samples, PTB women vagina were characterized by a decrease in Firmicutes, Lactobacillus, and an increase in diversity accompanied by the colonization of pathogenic bacteria such as Gardnerella, Atopobium and Prevotella. Twenty genus markers, including Lactobacillus, Prevotella, Streptococcus, and Gardnerella performed well in predicting PTB, with study-to-study transfer validation and LODO validation, different gestation validation showing good results, and in two independent cohorts (external WGS cohorts and woman samples WGS cohorts) in which the accuracy was maintained. PTB women have unique vaginal microbiota characteristics. A predictive model of PTB was constructed and its value validated from multiple perspectives.

Behavioral transcriptomic effects of triploidy and probiotic therapy (Bifidobacterium, Lactobacillus, and Lactococcus mixture) on juvenile Chinook salmon (Oncorhynchus tshawytscha).

Aquaculturists use polyploid fish to maximize production albeit with some unintended consequences including compromised behaviors and physiological function. Given benefits of probiotic therapies (e.g., improved immune response, growth, and metabolism), we explored probiotic supplementation (mixture of Bifidobacterium, Lactobacillus, and Lactococcus), to overcome drawbacks. We first examined fish gut bacterial community composition using 16S metabarcoding (via principal coordinate analyses and PERMANOVA) and determined probiotics significantly impacted gut bacteria composition (p = 0.001). Secondly, we examined how a genomic disruptor (triploidy) and diet supplements (probiotics) impact gene transcription and behavioral profiles of hatchery-reared Chinook salmon (Oncorhynchus tshawytscha). Juveniles from four treatment groups (diploid-regular feed, diploid-probiotic feed, triploid-regular feed, and triploid-probiotic feed; n = 360) underwent behavioral assays to test activity, exploration, neophobia, predator evasion, aggression/sociality, behavioral sensitivity, and flexibility. In these fish, transcriptional profiles for genes associated with neural functions (neurogenesis/synaptic plasticity) and biomarkers for stress response and development (growth/appetite) were (i) examined across treatments and (ii) used to describe behavioral phenotypes via principal component analyses and general linear mixed models. Triploids exhibited a more active behavioral profile (p = 0.002), and those on a regular diet had greater Neuropeptide Y transcription (p = 0.02). A growth gene (early growth response protein 1, p = 0.02) and long-term neural development genes (neurogenic differentiation factor, p = 0.003 and synaptysomal-associated protein 25-a, p = 0.005) impacted activity and reactionary profiles, respectively. Overall, our probiotic treatment did not compensate for triploidy. Our research highlights novel applications of behavioral transcriptomics for identifying candidate genes and dynamic, mechanistic associations with complex behavioral repertoires.

Impact of culture medium on the interpretation of qRT-PCR data in HepG2 incubated with lactobacilli.

Recently, an increasing number of studies have investigated the mechanism of action of lactobacilli in the treatment of non-alcoholic fatty liver disease. Using four computational tools (NormFinder, geNorm, Delta Ct, and BestKeeper), six potential reference genes (RGs) were analyzed in the human liver cell line HepG2 cultivated 24 h in the presence of two strains of heat-killed lactobacilli, Limosilactobacillus reuteri E and Lactiplantibacillus plantarum KG4, respectively, in different cultivation media [Dulbecco´s Modified Eagle´s Medium (DMEM) high glucose or Roswell Park Memorial Institute (RPMI)]. The analysis revealed that the suitability of RG was similar between the two lactobacilli but quite different between the two media. The commonly used RGs, 18S rRNA and glyceraldehyde-3-phosphate dehydrogenase were the most unstable in DMEM high glucose. Normalization of the mRNA expression of the target gene encoding sterol regulatory element-binding protein 1c (SREBP-1c) to different RGs resulted in different expression profiles. This demonstrates that validation of candidate RGs under specific experimental conditions is crucial for the correct interpretation of quantitative polymerase chain reaction data. In addition, the choice of media has a profound impact on the effect of lactobacilli on lipogenesis at the gene expression level, as shown by the transcription factor SREBP-1c.

Phosphate Uptake and Its Relation to Arsenic Toxicity in Lactobacilli.

The use of probiotic lactobacilli has been proposed as a strategy to mitigate damage associated with exposure to toxic metals. Their protective effect against cationic metal ions, such as those of mercury or lead, is believed to stem from their chelating and accumulating potential. However, their retention of anionic toxic metalloids, such as inorganic arsenic, is generally low. Through the construction of mutants in phosphate transporter genes (pst) in Lactiplantibacillus plantarum and Lacticaseibacillus paracasei strains, coupled with arsenate [As(V)] uptake and toxicity assays, we determined that the incorporation of As(V), which structurally resembles phosphate, is likely facilitated by phosphate transporters. Surprisingly, inactivation in Lc. paracasei of PhoP, the transcriptional regulator of the two-component system PhoPR, a signal transducer involved in phosphate sensing, led to an increased resistance to arsenite [As(III)]. In comparison to the wild type, the phoP strain exhibited no differences in the ability to retain As(III), and there were no observed changes in the oxidation of As(III) to the less toxic As(V). These results reinforce the idea that specific transport, and not unspecific cell retention, plays a role in As(V) biosorption by lactobacilli, while they reveal an unexpected phenotype for the lack of the pleiotropic regulator PhoP.

Mutualistic interactions of lactate-producing lactobacilli and lactate-utilizing Veillonella dispar: Lactate and glutamate cross-feeding for the enhanced growth and short-chain fatty acid production.

The human gut hosts numerous ecological niches for microbe-microbe and host-microbe interactions. Gut lactate homeostasis in humans is crucial and relies on various bacteria. Veillonella spp., gut lactate-utilizing bacteria, and lactate-producing bacteria were frequently co-isolated. A recent clinical trial has revealed that lactate-producing bacteria in humans cross-feed lactate to Veillonella spp.; however, their interspecies interaction mechanisms remain unclear. Veillonella dispar, an obligate anaerobe commonly found in the human gut and oral cavity, ferments lactate into acetate and propionate. In our study, we investigated the interaction between V. dispar ATCC 17748T and three representative phylogenetically distant strains of lactic acid bacteria, Lactobacillus acidophilus ATCC 4356T, Lacticaseibacillus paracasei subsp. paracasei ATCC 27216T, and Lactiplantibacillus plantarum ATCC 10241. Bacterial growth, viability, metabolism and gene level adaptations during bacterial interaction were examined. V. dispar exhibited the highest degree of mutualism with L. acidophilus. During co-culture of V. dispar with L. acidophilus, both bacteria exhibited enhanced growth and increased viability. V. dispar demonstrated an upregulation of amino acid biosynthesis pathways and the aspartate catabolic pathway. L. acidophilus also showed a considerable number of upregulated genes related to growth and lactate fermentation. Our results support that V. dispar is able to enhance the fermentative capability of L. acidophilus by presumably consuming the produced lactate, and that L. acidophilus cross-feed not only lactate, but also glutamate, to V. dispar during co-culture. The cross-fed glutamate enters the central carbon metabolism in V. dispar. These findings highlight an intricate metabolic relationship characterized by cross-feeding of lactate and glutamate in parallel with considerable gene regulation within both L. acidophilus (lactate-producing) and V. dispar (lactate-utilizing). The mechanisms of mutualistic interactions between a traditional probiotic bacterium and a potential next-generation probiotic bacterium were elucidated in the production of short-chain fatty acids.

Isolation, identification, and characterization of thermophilic lactic acid bacteria isolated from whey of Kars Kashar cheeses.

Kars Kashar cheese is an artisanal pasta-filata type cheese and geographically marked in Eastern Anatolia of Turkey. The aims of this research were to determine for the first time thermophilic lactic acid bacteria (LAB) of Kars Kashar cheese and characterize the technological properties of obtained isolates. In our research, a number of 15 samples of whey were collected from the different villages in Kars. These samples were incubated at 45 °C and used as the source material for isolating thermophilic LAB. A total of 250 colonies were isolated from thermophilic whey, and 217 of them were determined to be presumptive LAB based on their Gram staining and catalase test. A total of 170 isolates were characterized by their phenotypic properties and identified using the MALDI-TOF mass spectrometry method. Phenotypic identification of isolates displayed that Enterococcus and Lactobacillus were the predominant microbiota. According to MALDI-TOF MS identification, 89 isolates were identified as Enterococcus (52.35%), 57 isolates as Lactobacillus (33.53%), 23 isolates as Streptococcus (13.53%), and one isolate as Lactococcus (0.59%). All thermophilic LAB isolates were successfully identified to the species level and it has been observed that MALDI-TOF MS can be successfully used for the identification of selected LAB. The acidification and proteolytic activities of the isolated thermophilic LAB were examined, and the isolates designated for use as starter cultures were also genotypically defined.

Effect of stress urinary incontinence on vaginal microbial communities.

BACKGROUND: Postpartum women often experience stress urinary incontinence (SUI) and vaginal microbial dysbiosis, which seriously affect women's physical and mental health. Understanding the relationship between SUI and vaginal microbiota composition may help to prevent vaginal diseases, but research on the potential association between these conditions is limited. RESULTS: This study employed 16S rRNA gene sequencing to explore the association between SUI and vaginal dysbiosis. In terms of the vaginal microbiota, both species richness and evenness were significantly higher in the SUI group. Additionally, the results of NMDS and species composition indicated that there were differences in the composition of the vaginal microbiota between the two groups. Specifically, compared to postpartum women without SUI (Non-SUI), the relative abundance of bacteria associated with bacterial dysbiosis, such as Streptococcus, Prevotella, Dialister, and Veillonella, showed an increase, while the relative abundance of Lactobacillus decreased in SUI patients. Furthermore, the vaginal microbial co-occurrence network of SUI patients displayed higher connectivity, complexity, and clustering. CONCLUSION: The study highlights the role of Lactobacillus in maintaining vaginal microbial homeostasis. It found a correlation between SUI and vaginal microbiota, indicating an increased risk of vaginal dysbiosis. The findings could enhance our understanding of the relationship between SUI and vaginal dysbiosis in postpartum women, providing valuable insights for preventing bacterial vaginal diseases and improving women's health.

Cervical microbiota dysbiosis associated with high-risk Human Papillomavirus infection.

High-risk Human Papillomavirus (HR-HPV) genotypes, specifically HPV16 and HPV18, pose a significant risk for the development of cervical intraepithelial neoplasia and cervical cancer. In the multifaceted cervical microenvironment, consisting of immune cells and diverse microbiota, Lactobacillus emerges as a pivotal factor, wielding significant influence in both stabilizing and disrupting the microbiome of the reproductive tract. To analyze the distinction between the cervical microbiota and Lactobacillus-dominant/non-dominant status of HR-HPV and non-infected healthy women, sixty-nine cervical swab samples were analyzed, included 44 with HR-HPV infection and healthy controls. All samples were recruited from Human Papillomavirus-based cervical cancer screening program and subjected to 16s rRNA sequencing analysis. Alpha and beta diversity analyses reveal no significant differences in the cervical microbiota of HR-HPV-infected women, including 16 and 18 HPV genotypes, and those with squamous intraepithelial lesion (SIL), compared to a control group. In this study we identified significantly lower abundance of Lactobacillus mucosae in women with HR-HPV infection compared to the control group. Furthermore, changes in bacterial diversity were noted in Lactobacillus non-dominant (LND) samples compared to Lactobacillus-dominant (LD) in both HR-HPV-infected and control groups. LND samples in HR-HPV-infected women exhibited a cervical dysbiotic state, characterized by Lactobacillus deficiency. In turn, the LD HR-HPV group showed an overrepresentation of Lactobacillus helveticus. In summary, our study highlighted the distinctive roles of L. mucosae and L. helveticus in HR-HPV infections, signaling a need for further research to demonstrate potential clinical implications of cervical microbiota dysbiosis.

Investigating human-derived lactic acid bacteria for alcohol resistance.

BACKGROUND: Excessive alcohol consumption has been consistently linked to serious adverse health effects, particularly affecting the liver. One natural defense against the detrimental impacts of alcohol is provided by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH), which detoxify harmful alcohol metabolites. Recent studies have shown that certain probiotic strains, notably Lactobacillus spp., possess alcohol resistance and can produce these critical enzymes. Incorporating these probiotics into alcoholic beverages represents a pioneering approach that can potentially mitigate the negative health effects of alcohol while meeting evolving consumer preferences for functional and health-centric products. RESULTS: Five lactic acid bacteria (LAB) isolates were identified: Lactobacillus paracasei Alc1, Lacticaseibacillus rhamnosus AA, Pediococcus acidilactici Alc3, Lactobacillus paracasei Alc4, and Pediococcus acidilactici Alc5. Assessment of their alcohol tolerance, safety, adhesion ability, and immunomodulatory effects identified L. rhamnosus AA as the most promising alcohol-tolerant probiotic strain. This strain also showed high production of ADH and ALDH. Whole genome sequencing analysis revealed that the L. rhamnosus AA genome contained both the adh (encoding for ADH) and the adhE (encoding for ALDH) genes. CONCLUSIONS: L. rhamnosus AA, a novel probiotic candidate, showed notable alcohol resistance and the capability to produce enzymes essential for alcohol metabolism. This strain is a highly promising candidate for integration into commercial alcoholic beverages upon completion of comprehensive safety and functionality evaluations.

Vaginal microbiomes show ethnic evolutionary dynamics and positive selection of Lactobacillus adhesins driven by a long-term niche-specific process.

The vaginal microbiome's composition varies among ethnicities. However, the evolutionary landscape of the vaginal microbiome in the multi-ethnic context remains understudied. We perform a systematic evolutionary analysis of 351 vaginal microbiome samples from 35 multi-ethnic pregnant women, in addition to two validation cohorts, totaling 462 samples from 90 women. Microbiome alpha diversity and community state dynamics show strong ethnic signatures. Lactobacillaceae have a higher ratio of non-synonymous to synonymous polymorphism and lower nucleotide diversity than non-Lactobacillaceae in all ethnicities, with a large repertoire of positively selected genes, including the mucin-binding and cell wall anchor genes. These evolutionary dynamics are driven by the long-term evolutionary process unique to the human vaginal niche. Finally, we propose an evolutionary model reflecting the environmental niches of microbes. Our study reveals the extensive ethnic signatures in vaginal microbial ecology and evolution, highlighting the importance of studying the host-microbiome ecosystem from an evolutionary perspective.

Challenges for heat stress: Intestinal culturable bacteria of Lohmann Brown chickens.

This study aimed to assess how heat stress, specifically within the range of 35-38 °C, affects the populations of culturable intestinal lactobacilli, enterococci, and Escherichia coli, as well as the expression of Heat Shock Proteins (HSP70), in Lohmann Brown chickens. It also explored the influence of the chickens' blood transferrin and ceruloplasmin genotypes on these responses. Thirty chickens underwent eight hours of heat stress, maintained at an average temperature of 37 °C and a relative humidity of 75-80%, with continuous access to food and water. Behavioral monitoring was conducted throughout to prevent excessive heat-related mortality. The Lohmann Brown chickens from the Yerevan "Arax" poultry farm were initially classified based on their blood transferrin and ceruloplasmin genotypes to investigate potential correlations between intestinal bacterial composition and variations in these polymorphisms. A significant correlation was found between heat stress and the abundance of culturable enterococci within the intestinal microbiota, regardless of chicken TfAB, TfBC, CpAB, CpCC and TfAB, TfBC, CpAB, CpCD genotypes. Heat stress led to nearly double the HSP70 levels in chicken blood, along with a reduction in the culturable enterococci population by at least 10,000-fold in the intestinal microbiota. These findings are significant for targeted management strategies to mitigate heat stress in chicken populations.

Antibacterial potential of lactic acid bacteria isolated from raw cow milk in Sylhet district, Bangladesh: A molecular approach.

BACKGROUND: The most prevalent probiotic bacterium employed in the food industry is Lactobacillus because it can produce metabolites with antibacterial capabilities and exhibits hostility towards infections and microorganisms that cause spoilage. AIM: This study set out to identify naturally occurring Lactobacillus and plantaricin (pln EF) coding genes in raw cow milk and to assess the antibacterial potency of isolated Lactobacillus isolates. METHODS: Following enrichment in De Man, Rogosa and Sharpe (MRS) broth, single colonies were isolated, and pure colonies were obtained by streaking on MRS agar. The 16S rRNA gene was amplified using polymerase chain reaction (PCR) to confirm the cultural positivity of all isolates. Additionally, the presence of plantaricin was verified by targeting the pln EF gene through PCR. OUTCOME: Out of the 166 raw milk specimens acquired from cows, 153 (91.17%; CI: 86.98-95.76) were identified as positive for Lactobacillus through both culture and biochemical screening. Subsequently, 121 (72.89%; CI: 65.46-79.49) of the isolates were affirmed to harbour Lactobacillus through PCR analysis. Within this subset, 6 isolates (4.96%; CI: 1.84-10.48) were found to possess the plnEF gene. When exposed to Lactobacillus isolates, Salmonella Typhimurium and Salmonella enterica displayed an average maximum zone of inhibition with a diameter measuring 24 mm. In contrast, Escherichia coli exhibited an average minimum zone of inhibition, featuring a diameter of 11 mm. Additionally, the Lactobacillus isolates demonstrated inhibitory zones against Staphylococcus aureus, Klebsiella pneumoniae and Klebsiella oxytoca, measuring 14, 22 and 19 mm, respectively. CLINICAL SIGNIFICANCE: Lactic acid bacteria, particularly Lactobacilli, are plentiful in cow milk and possess broad-spectrum antibacterial properties.

Vaginal microbiota molecular profiling and diagnostic performance of artificial intelligence-assisted multiplex PCR testing in women with bacterial vaginosis: a single-center experience.

Background: Bacterial vaginosis (BV) is a most common microbiological syndrome. The use of molecular methods, such as multiplex real-time PCR (mPCR) and next-generation sequencing, has revolutionized our understanding of microbial communities. Here, we aimed to use a novel multiplex PCR test to evaluate the microbial composition and dominant lactobacilli in non-pregnant women with BV, and combined with machine learning algorithms to determine its diagnostic significance. Methods: Residual material of 288 samples of vaginal secretions derived from the vagina from healthy women and BV patients that were sent for routine diagnostics was collected and subjected to the mPCR test. Subsequently, Decision tree (DT), random forest (RF), and support vector machine (SVM) hybrid diagnostic models were constructed and validated in a cohort of 99 women that included 74 BV patients and 25 healthy controls, and a separate cohort of 189 women comprising 75 BV patients, 30 intermediate vaginal microbiota subjects and 84 healthy controls, respectively. Results: The rate or abundance of Lactobacillus crispatus and Lactobacillus jensenii were significantly reduced in BV-affected patients when compared with healthy women, while Lactobacillus iners, Gardnerella vaginalis, Atopobium vaginae, BVAB2, Megasphaera type 2, Prevotella bivia, and Mycoplasma hominis were significantly increased. Then the hybrid diagnostic models were constructed and validated by an independent cohort. The model constructed with support vector machine algorithm achieved excellent prediction performance (Area under curve: 0.969, sensitivity: 90.4%, specificity: 96.1%). Moreover, for subjects with a Nugent score of 4 to 6, the SVM-BV model might be more robust and sensitive than the Nugent scoring method. Conclusion: The application of this mPCR test can be effectively used in key vaginal microbiota evaluation in women with BV, intermediate vaginal microbiota, and healthy women. In addition, this test may be used as an alternative to the clinical examination and Nugent scoring method in diagnosing BV.

Menopausal status induces vaginal dysbiosis in women with human papillomavirus infection.

In this study, we examined the difference in the vaginal microbiota of women infected with human papillomavirus (HPV), according to menopausal status. A total of 75 cervicovaginal swab samples from 38 pre- and 37 postmenopausal women with HPV infection were obtained from the Korean HPV cohort. Vaginal microbiota analysis, including microbial diversity and specific bacterial abundances, was performed using 16S rRNA gene sequencing. The mean age of the pre- and postmenopausal women were 29.5 and 55.8 years, respectively (p < 0.0001). Lactobacillus spp. were predominant in both groups; however, a marked decrease was observed in postmenopausal women compared to premenopausal women (44.3% vs. 74.2%). Various anaerobic bacteria also showed a relatively high abundance in the postmenopausal group; Atopobium vagina and Gardnerella vaginalis significantly increased in postmenopausal women. Interestingly, no significant differences in bacterial richness were observed between the two groups. However, significant differences in beta-diversity were observed using the Bray-Curtis (p = 0.001), Generalized UniFrac (p = 0.002), Jensen-Shannon (p = 0.001), and UniFrac algorithms (p = 0.002). Theres results indicate that postmenopausal women with HPV infection exhibited a higher degree of vaginal dysbiosis than premenopausal women. Further, HPV-infected postmenopausal women had increased vaginal microbial diversity, characterized by an increase in anaerobic bacteria and concomitant depletion of Lactobacillus spp.

Characteristics of cervicovaginal microflora at different cervical maturity during late pregnancy: A nested case-control study.

OBJECTIVE: The mechanism of cervical ripening in late pregnancy is still unclear. The vaginal microbiome has been reported to correlate with the preterm birth and short cervix in pregnant women. However, the associations between the cervical maturity and the vaginal microbiome are still poorly understood. We aim to analyze the cervicovaginal microflora in women with ripe cervix and in those who are unripe when delivering at term. METHODS: Cervicovaginal swabs were collected between 40 and 41 weeks of gestation from the following 2 different groups of patients: ripe group (n = 25) and unripe group (n = 25). Samples were tested using 16S ribosomal RNA gene high-throughput sequencing and analyzed by bioinformatics platform. RESULTS: This study highlights the relationship between cervical maturity during late pregnancy and the composition of the cervicovaginal microflora. Both α- and ß-diversity analyses demonstrated significant differences between women with a ripe cervix and those with an unripe cervix. Notably, the Lactobacillus profile was found to be closely linked to cervical maturity. There was a significant difference in the vaginal community state type, with CST IV being more prevalent in women with an unripe cervix. Furthermore, the association between CST IV and the unripe cervix group, as indicated by the odds ratio of 8.6, underscores its relevance in evaluating cervical maturity, when compared to other Lactobacillus-dominant community state types. Additionally, several bacterial taxa, particularly Lactobacillus, exhibited differential relative abundances between the two groups. CONCLUSION: This study provided significant evidence regarding the relationship between the vaginal microbiome and cervical maturity, highlighting the differential diversity, community state types, and specific bacterial taxa, such as Lactobacillus, that are associated with cervical maturation status. These findings contributed to our understanding of the dynamics of the cervicovaginal microflora during late pregnancy and its implications for cervical health.

Resistance role of Lactobacillus sp. and Lactococcus sp. to copper ions in healthy children's intestinal microorganisms.

Heavy metal exposure is closely associated with gut microbe function and tolerance. However, intestinal microbe responses in children to different copper ion (Cu2+) concentrations have not yet been clarified. Here, in vitro cultivation systems were established for fecal microbe control and Cu2+-treated groups in healthy children. 16S rDNA high-throughput sequencing, meta-transcriptomics and metabolomics were used here to identify toxicity resistance mechanisms at microbiome levels. The results showed that Lactobacillus sp. and Lactococcus sp. exerted protective effects against Cu2+ toxicity, but these effects were limited by Cu2+ concentration. When the Cu2+ concentration was ≥ 4 mg/L, the abundance of Lactobacillus sp. and Lactococcus sp. significantly decreased, and the pathways of antioxidant activity and detoxification processes were enriched at 2 mg/L Cu2+, and beneficial metabolites accumulated. However, at high concentrations of Cu2+ (≥4 mg/L), the abundance of potential pathogen increased, and was accompanied by a downregulation of genes in metabolism and detoxification pathways, which meant that the balance of gut microbiota was disrupted and toxicity resistance decreased. From these observations, we identified some probiotics that are tolerant to heavy metal Cu2+, and warn that only when the concentration limit of Cu2+ in food is 2 mg/L, then a balanced gut microbiota can be guaranteed in children, thereby providing protection for their health.

Microbial interventions in yak colibacillosis: Lactobacillus-mediated regulation of intestinal barrier.

Introduction: The etiology of Escherichia coli in yaks, along with its drug resistance, results in economic losses within the yak breeding industry. The utilization of lactic acid bacteria treatment has emerged as a viable alternative to antibiotics in managing colibacillosis. Methods: To elucidate the therapeutic mechanisms of Lactobacillus against Escherichia coli-induced intestinal barrier damage in yaks, we employed yak epithelial cells as the experimental model and established a monolayer epithelial barrier using Transwell. The study encompassed four groups: a control group, a model group (exposed to E. coli O78), a low-dose Lactobacillus group (E. coli O78 + 1 × 105CFU LAB), and a high-dose Lactobacillus group (E. coli O78 + 1 × 107CFU LAB). Various techniques, including transmembrane resistance measurement, CFU counting, RT-qPCR, and Western Blot, were employed to assess indicators related to cell barrier permeability and tight junction integrity. Results: In the Model group, Escherichia coli O78 significantly compromised the permeability and tight junction integrity of the yak epithelial barrier. It resulted in decreased transmembrane resistance, elevated FD4 flux, and bacterial translocation. Furthermore, it downregulated the mRNA and protein expression of MUC2, Occludin, and ZO-1, while upregulating the mRNA expression and protein expression of FABP2 and Zonulin, thereby impairing intestinal barrier function. Contrastingly, Lactobacillus exhibited a remarkable protective effect. It substantially increased transmembrane resistance, mitigated FD4 flux, and reduced bacterial translocation. Moreover, it significantly upregulated the mRNA and protein expression of MUC2, Occludin, and ZO-1, while downregulating the mRNA and protein expression of FABP2 and Zonulin. Notably, high-dose LAB demonstrated superior regulatory effects compared to the low-dose LAB group. Discussion: In conclusion, our findings suggest that Lactobacillus holds promise in treating yak colibacillosis by enhancing mucin and tight junction protein expression. Furthermore, we propose that Lactobacillus achieves these effects through the regulation of Zonulin.

Uterine fibroids and longitudinal profiles of the vaginal microbiota in a cohort presenting for transvaginal ultrasound.

Bacterial vaginosis, characterized in part by low levels of vaginal Lactobacillus species, has been associated with pro-inflammatory cytokines which could fuel uterine fibroid development. However, prior work on the associations between uterine fibroids and vaginal bacteria is sparse. Most studies have focused on assessment of individual taxa in a single sample. To address research gaps, we sought to compare short, longitudinal profiles of the vaginal microbiota in uterine fibroid cases versus controls with assessment for hormonal contraceptives (HCs), a possible confounder associated with both protection from fibroid development and increases in Lactobacillus-dominated vaginal microbiota. This is a secondary analysis of 83 reproductive-age cisgender women who presented for transvaginal ultrasound (TVUS) and self-collected mid-vaginal swabs daily for 1-2 weeks before TVUS (Range: 5-16 days, n = 697 samples). Sonography reports detailed uterine fibroid characteristics (N = 21 cases). Vaginal microbiota was assessed by 16S rRNA gene amplicon sequencing and longitudinal microbiota profiles were categorized by hierarchical clustering. We compared longitudinal profiles of the vaginal microbiota among fibroid cases and controls with exact logistic regression. Common indications for TVUS included pelvic mass (34%) and pelvic pain (39%). Fibroid cases tended to be older and report Black race. Cases less often reported HCs versus controls (32% vs. 58%). A larger proportion of cases had low-Lactobacillus longitudinal profiles (48%) than controls (34%). In unadjusted analysis, L. iners-dominated and low-Lactobacillus profiles had higher odds of fibroid case status compared to other Lactobacillus-dominated profiles, however these results were not statistically significant. No association between vaginal microbiota and fibroids was observed after adjusting for race, HC and menstruation. Results were consistent when number of fibroids were considered. There was not a statistically significant association between longitudinal profiles of vaginal microbiota and uterine fibroids after adjustment for common confounders; however, the study was limited by small sample size.