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AbstractType 2 diabetes mellitus (T2DM) is one of the metabolic diseases with the highest morbidity rates in the world. Probiotics have positive health impacts on human health and a considerable amount of research has demonstrated their beneficial effects in treating T2DM. However, probiotic intervention in T2DM has complex mechanisms because the pathogenesis of T2DM is complex. This review summarized the mechanisms of probiotic intervention in diabetes from the perspective of diabetes pathogenesis. First, the objectives of probiotic intervention in diabetes aimed at the intestinal tract reparative effects, pancreatic function, host metabolism and self-recovery were comprehensively reviewed. Next, we concluded the clinical application status of ingested probiotics in patients with T2DM, and an obvious imbalance exists between theoretical probiotic research and clinical applications. Finally, we summarized the emerging research on probiotic interventions in T2DM and analyzed the literature in this regard, including next-generation probiotics; suggestions for probiotics consumption with the aim of diabetic complications; as well as the association between novel mechanisms of diabetes remission with the potential for probiotic intervention. In conclusion, this review sheds light on the potential role of probiotics, from proposed mechanisms to prospects in relieving T2DM. [ABSTRACT FROM AUTHOR]

BACKGROUND: Streptococcus thermophilus is an important strain widely used in dairy fermentation, with distinct urea metabolism characteristics compared to other lactic acid bacteria. The conversion of urea by S. thermophilus has been shown to affect the flavor and acidification characteristics of milk. Additionally, urea metabolism has been found to significantly increase the number of cells and reduce cell damage under acidic pH conditions, resulting in higher activity. However, the physiological role of urea metabolism in S. thermophilus has not been fully evaluated. A deep understanding of this metabolic feature is of great significance for its production and application. Genome‐scale metabolic network models (GEMs) are effective tools for investigating the metabolic network of organisms using computational biology methods. Constructing an organism‐specific GEM can assist us in comprehending its characteristic metabolism at a systemic level. RESULTS: In the present study, we reconstructed a high‐quality GEM of S. thermophilus S‐3 (iCH492), which contains 492 genes, 608 metabolites and 642 reactions. Growth phenotyping experiments were employed to validate the model both qualitatively and quantitatively, yielding satisfactory predictive accuracy (95.83%), sensitivity (93.33%) and specificity (100%). Subsequently, a systematic evaluation of urea metabolism in S. thermophilus was performed using iCH492. The results showed that urea metabolism reduces intracellular hydrogen ions and creates membrane potential by producing and transporting ammonium ions. This activation of glycolytic fluxes and ATP synthase produces more ATP for biomass synthesis. The regulation of fluxes of reactions involving NAD(P)H by urea metabolism improves redox balance. CONCLUSION: Model iCH492 represents the most comprehensive knowledge‐base of S. thermophilus to date, serving as a potent tool. The evaluation of urea metabolism led to novel insights regarding the role of urease. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The two essential editing elements in the clustered regularly interspaced short palindromic repeats (CRISPR) editing system are promoter and single‐guide RNA (sgRNA), the latter of which determines whether Cas protein can precisely target a specific location to edit the targeted gene. Therefore, the selection of sgRNA is crucial to the efficiency of the CRISPR editing system. Various online prediction tools for sgRNA are currently available. These tools can predict all possible sgRNAs of the targeted gene and rank sgRNAs according to certain scoring criteria according to the demands of the user. RESULTS: We designed sgRNAs for Lactococcus lactis NZ9000 LLNZ_RS02020 (ldh) and LLNZ_RS10925 (upp) individually using online prediction software – CRISPOR – and successfully constructed a series of knockout strains to allow comparison of the knockout efficiency of each sgRNA and analyze the differences between software predictions and actual experimental results. CONCLUSION: Our experimental results showed that the actual editing efficiency of the screened sgRNAs did not match the predicted results – a phenomenon that suggests that established findings from eukaryotic studies are not universally applicable to prokaryotes. Software prediction can still be used as a tool for the initial screening of sgRNAs before further selection of suitable sgRNAs through experimental experience. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: It has been well accepted that lactic acid bacteria (LAB) are the main bacterial genera present during the brewing of Chinese rice wine (CRW). LAB plays a decisive role in the flavor quality of CRW; however, its application in CRW has previously been overlooked. Therefore, effects of different LAB as co‐fermenter on the flavor characteristics of CRW were investigated. RESULTS: Co‐fermentation of LAB increased the utilization rate of reducing sugar, concentration of lactic acid, amino acid nitrogen and total acidity, as well as the content of volatile flavor compounds. Different LAB doses had little effect on the flavor profiles of CRW, but the species of LAB greatly affected the flavor characteristic. The flavor of CRW co‐fermented with Lactococcus lactis was characterized by long‐chain fatty acid ethyl esters, while co‐fermentation with Weissella confusa highlighted the ethyl esters of low molecular weight and short carbon chains in the resultant CRW. Alcohol compounds were dominant in the CRW co‐fermented using Pediococcus pentosaceus. CONCLUSION: The co‐fermentation of LAB increased the number of volatile flavor compounds, especially esters. LAB exhibited great potential in the application of CRW industry to enrich the flavor characteristics and enhance the flavor diversity of the final product. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Human serum albumin (HSA) is the most abundant protein in plasma, playing crucial roles in regulating osmotic pressure and maintaining protein homeostasis. It is widely applied in the clinical treatment of various diseases. HSA can be purified from plasma or produced using recombinant DNA technology. Due to the improved efficiency and reduced costs, a growing body of research has focused on enhancing albumin production through bacterial strain overexpression. However, there have been few studies on the effect of albumin on the characteristics of the overexpressing‐strain itself, particularly stress resistance. In this study, we utilized Lactiplantibacillus plantarum (L. plantarum) AR113 as the expression host and successfully constructed the albumin overexpression strain AR113‐pLLY01 through gene editing technology. The successful expression of albumin was achieved and subsequently compared with the wild‐type strain AR113‐pIB184.The results demonstrated that the survival rate of AR113‐pLLY01 was also significantly better than that of AR113‐pIB184 after lyophilization. In addition, AR113‐pLLY01 exhibited a significantly better protective effect than AR113‐pIB184 at pH 3, indicating that albumin possesses a certain tolerance to acidic stress. At bile salt concentrations higher than 0.03%, both strains showed limited growth, but at a concentration of 0.02%, AR113‐pLLY01 had a significant protective effect.This study suggest that albumin can improve strain tolerance, which has significant implications for future applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Effectively managing foodborne pathogens is imperative in food processing, where probiotics play a crucial role in pathogen control. This study focuses on the Lactiplantibacillus plantarum AR113 and its gene knockout strains, exploring their antimicrobial properties against Escherichia coli O157:H7 and Staphylococcus aureus . Antimicrobial assays revealed that the inhibitory effect of AR113 increases with its growth and the potential bacteriostatic substance is acidic. AR113Δ ldh, surpassed AR113Δ 0273&2024 , exhibited a complete absence of bacteriostatic properties, which indicates that lactic acid is more essential than acetic acid in the bacteriostatic effect of AR113. However, the exogenous acid validation test affirmed the equivalent superior bacteriostatic effect of lactic acid and acetic acid. Notably, AR113 has high lactate production and deletion of the ldh gene not only lacks lactate production but also affects acetic production. This underscores the ldh gene's pivotal role in the antimicrobial activity of AR113. In addition, among all the selected knockout strains, AR113Δ tagO and Δ ccpA also had lower antimicrobial effects, suggesting the importance of tagO and ccpA genes of AR113 in pathogen control. This study contributes insights into the antimicrobial potential of AR113 and stands as the pioneering effort to use knockout strains for comprehensive bacteriostatic investigations.