Bioscience of Microbiota, Food and Health最新文献

{"title":"Differential effects of orally administered <i>Lactobacillus acidophilus</i> L-55 on the gene expression of cytokines and master immune switches in the ileum and spleen of laying hen with an attenuated Newcastle disease virus vaccine.","authors":"Hung Hoang Son Pham,&nbsp;Yusuke Fujii,&nbsp;Kensuke Arakawa,&nbsp;Toshimitsu Hatabu","doi":"10.12938/bmfh.2021-026","DOIUrl":"https://doi.org/10.12938/bmfh.2021-026","url":null,"abstract":"<p><p>This study aimed to evaluate the benefits of oral administration of <i>Lactobacillus acidophilus</i> strain L-55 (LaL-55) to chickens inoculated with a Newcastle disease virus (NDV)-based live-attenuated vaccine by examining the mRNA expression of several genes related to viral infection in the spleen and ileum by quantitative reverse transcription polymerase chain reaction. In the spleen, interferon (IFN)-α was significantly higher in the low- and middle-dose LaL-55 groups at 6 weeks than at 4 weeks. IFN regulatory factor (IRF)-3 and IRF-7 expression was significantly higher in the low-dose LaL-55 group than in the middle- and high-dose LaL-55 groups. In the ileum, melanoma differentiation-associated gene 5 showed a dose-dependent increase at 4 weeks. IFN-γ and IRF-7 showed dose-dependent increases at 6 weeks. These results suggested that LaL-55 boosts the immune response to the NDV vaccine, albeit by different mechanisms in the spleen and ileum.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 1","pages":"12-19"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/97/e7/bmfh-41-012.PMC8727056.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39825707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of antigens recognized by salivary IgA using microbial protein microarrays.","authors":"Koji Hamuro, Hiroshi Saito, Takao Saito, Noriyuki Kohda","doi":"10.12938/bmfh.2022-014","DOIUrl":"10.12938/bmfh.2022-014","url":null,"abstract":"<p><p>Secretory IgA plays an important role in the mucosal immune system for protection against pathogens. However, the antigens recognized by these antibodies have only been partially studied. We comprehensively investigated the antigens bound by salivary IgA in healthy adults using microbial protein microarrays. This confirmed that saliva contained IgA antibodies that bind to a variety of pathogenic microorganisms, including spike proteins of severe acute respiratory syndrome coronavirus 2, severe acute respiratory syndrome coronavirus, Middle East respiratory syndrome coronavirus, and other human coronavirus species. Also, many subtypes and strains of influenza virus were bound, regardless of the seasonal or vaccine strains. Salivary IgA also bound many serogroups and serovars of <i>Escherichia coli</i> and <i>Salmonella</i>. Taken together, these findings suggest that salivary IgA, which exhibits broad reactivity, is likely an essential element of the mucosal immune system at the forefront of defense against infection.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 4","pages":"177-184"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/15/05/bmfh-41-177.PMC9533030.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40339581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of gut microbiota and short-chain fatty acids in <i>Strongyloides stercoralis</i>-infected patients in a rural community.","authors":"Hai Thi Nguyen,&nbsp;Nuttanan Hongsrichan,&nbsp;Kitti Intuyod,&nbsp;Porntip Pinlaor,&nbsp;Manachai Yingklang,&nbsp;Apisit Chaidee,&nbsp;Chatchawan Sengthong,&nbsp;Thatsanapong Pongking,&nbsp;Rungthiwa Dangtakot,&nbsp;Ditsayathan Banjong,&nbsp;Sirirat Anutrakulchai,&nbsp;Ubon Cha'on,&nbsp;Somchai Pinlaor","doi":"10.12938/bmfh.2021-054","DOIUrl":"https://doi.org/10.12938/bmfh.2021-054","url":null,"abstract":"<p><p>Intestinal parasitic infections can change gut microbiota and short-chain fatty acids (SCFAs). We aimed to study the interaction among <i>Strongyloides stercoralis</i>, human gut microbiota, and serum SCFAs in a community. Fifty-two subjects in Donchang sub-district, Khon Kaen Province, northeastern Thailand, were included based on specific inclusion and exclusion criteria. Characteristics of the participants were matched between those positive for <i>S. stercoralis</i> infection alone (no other intestinal parasites; Ss+, n=26) and uninfected controls (infection status confirmed by polymerase chain reaction (PCR); Ss-, n=26). Serum short-chain fatty acids were evaluated by gas chromatography-mass spectrometry. DNA was extracted from individual faecal samples and then pooled into two groups (Ss+ and Ss-) for amplification and sequencing of the V3-V4 region of the 16S gene with next-generation technology. We explored the impact of infection with <i>S. stercoralis</i> on the faecal microbiota: individuals infected with this parasite exhibited increased alpha diversity of bacteria. At the genus level, gut microbiota in Ss+ patients showed high abundances of <i>Escherichia-Shigella</i> and <i>Bacteroides</i> but low abundances of the genera <i>Bifidobacterium, Lactobacillus,</i> and <i>Blautia.</i> PCR of individual samples to identify certain species of interest gave results consistent with those from next-generation sequencing of pooled samples and showed that significantly more Ss+ samples contained <i>Bacteroides fragilis</i>. Intriguingly, a major SCFA, acetic acid, was significantly decreased in <i>S. stercoralis</i> infection. In conclusion, <i>S. stercoralis</i> infection caused an imbalance of gut microbiota and decreased acetic acid in serum. This information adds to the knowledge concerning the effect of intestinal nematode-related chronic diseases.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 3","pages":"121-129"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/25/00/bmfh-41-121.PMC9246423.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40629814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report on the probiotic potential of <i>Mammaliicoccus sciuri</i> isolated from raw goat milk.","authors":"Tahir Naqqash,&nbsp;Nadia Wazir,&nbsp;Kashif Aslam,&nbsp;Ghulam Shabir,&nbsp;Muhammad Tahir,&nbsp;Rehan Sadiq Shaikh","doi":"10.12938/bmfh.2021-022","DOIUrl":"https://doi.org/10.12938/bmfh.2021-022","url":null,"abstract":"<p><p>Probiotics are considered effective microbial dietary supplements that provide beneficial effects to consumers, usually by restoring or improving gut microflora. Goat milk is one of the rich sources of probiotics as well as nutrients. Therefore, the primary aim of this research was to isolate and evaluate the potential of novel indigenous probiotic strains present in goat milk. Six different raw goat milk samples were collected from different areas of Multan, Pakistan. For bacterial characterization, samples were cultured and isolated on MRS agar plates for different morphological and biochemical tests. The probiotic potential of the six isolates, all of which were gram positive (G1, G2, G3, G4, G5, and G6) and five of which were catalase negative (all except G1), were assessed via a milk coagulation assay and antimicrobial activity, pH tolerance, phenol tolerance, and sodium chloride (NaCl) tolerance tests, which revealed that all the isolates coagulated in milk and showed protease and lipase activity, except G3. All six isolates showed tolerance against 0.2% phenol and 2-4% NaCl and were able to survive in both alkaline and acidic conditions. Only five isolates showed antimicrobial activity against indicator strain <i>Aspergillus niger</i> strain STA9, validating their probiotic nature. The most potent bile-tolerant and bacteriocin-producing isolate, G1, also showed γ-hemolytic activity and resistance to penicillin but showed susceptibility to other antibiotics. The lactic acid-producing (0.60% titratable acidity) G1 isolate was identified as a novel strain of <i>Mammaliicoccus sciuri</i> based on 16S rDNA sequencing. The above findings suggest that the potent <i>M. sciuri</i> GMN01 strain can serve as a potential probiotic strain. A potent probiotic strain isolated from raw goat milk could be utilized as a dietary supplement, and goat milk could become an alternative to other sources of milk, particularly cow milk. However, safety aspects of this strain require further investigation because the present safety tests are insufficient to conclude that the GMN01 isolate is safe.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 4","pages":"149-159"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/8c/bf/bmfh-41-149.PMC9533028.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40337654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of respiratory microbiota in the protection against viral diseases: respiratory commensal bacteria as next-generation probiotics for COVID-19.","authors":"Bruno G N Andrade,&nbsp;Rafael R C Cuadrat,&nbsp;Fernanda Raya Tonetti,&nbsp;Haruki Kitazawa,&nbsp;Julio Villena","doi":"10.12938/bmfh.2022-009","DOIUrl":"https://doi.org/10.12938/bmfh.2022-009","url":null,"abstract":"<p><p>On March 11, 2020, the World Health Organization declared a pandemic of coronavirus infectious disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and imposed the biggest public health challenge for our civilization, with unforeseen impacts in the subsequent years. Similar to other respiratory infections, COVID-19 is associated with significant changes in the composition of the upper respiratory tract microbiome. Studies have pointed to a significant reduction of diversity and richness of the respiratory microbiota in COVID-19 patients. Furthermore, it has been suggested that <i>Prevotella</i>, <i>Staphylococcus,</i> and <i>Streptococcus</i> are associated with severe COVID-19 cases, while <i>Dolosigranulum</i> and <i>Corynebacterium</i> are significantly more abundant in asymptomatic subjects or with mild disease. These results have stimulated the search for new microorganisms from the respiratory microbiota with probiotic properties that could alleviate symptoms and even help in the fight against COVID-19. To date, the potential positive effects of probiotics in the context of SARS-CoV-2 infection and COVID-19 pandemics have been extrapolated from studies carried out with other viral pathogens, such as influenza virus and respiratory syncytial virus. However, scientific evidence has started to emerge demonstrating the capacity of immunomodulatory bacteria to beneficially influence the resistance against SARS-CoV-2 infection. Here we review the scientific knowledge regarding the role of the respiratory microbiota in viral infections in general and in the infection caused by SARS-CoV-2 in particular. In addition, the scientific work that supports the use of immunomodulatory probiotic microorganisms as beneficial tools to reduce the severity of respiratory viral infections is also reviewed. In particular, our recent studies that evaluated the role of immunomodulatory <i>Dolosigranulum pigrum</i> strains in the context of SARS-CoV-2 infection are highlighted.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 3","pages":"94-102"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/3c/da/bmfh-41-094.PMC9246420.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40513933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The beneficial effects of exercise on glucose and lipid metabolism during statin therapy is partially mediated by changes of the intestinal flora.","authors":"Lijun Wang,&nbsp;Baihua Zhou,&nbsp;Xinying Li,&nbsp;Yang Wang,&nbsp;Xiu Mei Yang,&nbsp;Hongwei Wang,&nbsp;Jun Yan,&nbsp;Jiakun Dong","doi":"10.12938/bmfh.2021-024","DOIUrl":"https://doi.org/10.12938/bmfh.2021-024","url":null,"abstract":"<p><p>Recent research has confirmed that moderate-intensity exercise affects the gut microbiome composition and improves cardiac function in an animal model after myocardial infarction (MI). However, few studies have investigated the effects of exercise on glucose and lipid metabolism in patients with coronary heart disease (CHD) receiving a statin treatment and successful percutaneous coronary intervention (PCI). Meanwhile, since statin therapy may lead to the risk of an increase in blood glucose level in CHD patients, we hypothesized that moderate-intensity exercise may be helpful for regulating glucose-lipid metabolism and stabilizing the blood glucose level in CHD patients. Therefore, to confirm our conjecture, we conducted a clinical retrospective study and animal experiment, respectively. The clinical study involved a total of 501 statin-treated patients with CHD after PCI. According to the study protocol, patients were divided into the following three groups: a non-exercise group, exercise at the recommended standard group, and exercise not at the recommended standard group. We found that qualified moderate-intensity exercise decreased blood glucose and lipid levels at follow-up at a mean of 2.2 years, and the incidence of new-onset diabetes showed a downward trend compared with the non-exercise and exercise not at the recommended standard groups. Furthermore, we used a high-fat rat model to explore an additional mechanism of the beneficial effects of exercise-based management on glucose-lipid metabolism apart from the known mechanism. We used 16S rRNA high-throughput sequencing technology to analyze the changes induced by exercise in the composition of intestinal flora in experimental rats. We found that rats that exercised with or without statin administration had lower plasma glucose and lipid levels and that these parameters were higher in the control and statin-treated rats that did not exercise. These results were consistent with the human study. The results from high-throughput sequencing of the intestinal flora of rats showed, to the best of our knowledge, that exercise leads to an increased relative abundance of <i>Akkermansia muciniphila,</i> which contributes to improved glucose and lipid metabolism. Based on our current results, we suggest that moderate-intensity exercise can improve glucose and lipid metabolism and prevent statin treatment-related side effects, such as hyperglycemia, in patients after PCI. Exercise could facilitate the applicability of statins for lower lipid levels. Exercise training also provides additional benefits, such as alteration of the gut microbiota, which contributes to improved glucose and lipid metabolism.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 3","pages":"112-120"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/67/84/bmfh-41-112.PMC9246419.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40629815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"<i>Lactococcus lactis</i> subsp. <i>cremoris</i> C60 induces macrophages activation that enhances CD4+ T cell-based adaptive immunity.","authors":"Suguru Saito,&nbsp;Alato Okuno,&nbsp;Nanae Kakizaki,&nbsp;Toshio Maekawa,&nbsp;Noriko M Tsuji","doi":"10.12938/bmfh.2021-057","DOIUrl":"https://doi.org/10.12938/bmfh.2021-057","url":null,"abstract":"<p><p><i>Lactococcus lactis</i> subsp. <i>cremoris</i> C60 is a probiotic strain that induces diverse functional modifications in immune cells. In this report, as a novel effect of C60 on myeloid lineage cells, we show that C60 enhances the immunological function of macrophages that consequently promotes CD4+ T cell activity in an antigen-dependent manner. Heat-killed (HK) C60 induced the production of pro-inflammatory cytokines in thioglycolate-elicited peritoneal macrophages (TPMs) much stronger than Toll-like receptor (TLR) ligand stimulation. The HK-C60 treatment also augmented the expression of antigen-presenting and co-stimulatory molecules, such as major histocompatibility complex (MHC) class II, CD80, and CD86, as well as antigen uptake in TPMs. These HK-C60-mediated functional upregulations in TPMs resulted in the promotion of CD4+ T cell activation in an antigen-dependent manner. Interestingly, the TPMs that originated from the mice fed the HK-C60 diet showed pre-activated characteristics, which was confirmed by the upregulation of cytokine production and antigen presentation-related molecule expression under lipopolysaccharide (LPS) stimulation. Furthermore, the antigen-dependent CD4+ T cell activation was also enhanced by the TPMs. This implied that antigen presentation activity was enhanced in the TPMs that originated from the HK-C60 diet mice. Thus, C60 effectively upregulates the immunological function of macrophages that directly connects to CD4+ T cell-based adaptive immunity.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 3","pages":"130-136"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/73/42/bmfh-41-130.PMC9246417.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40629816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The gut microbiota of non-obese Japanese pregnant women with gestational diabetes mellitus.","authors":"Kei Tanaka,&nbsp;Gaku Harata,&nbsp;Kenji Miyazawa,&nbsp;Fang He,&nbsp;Shinji Tanigaki,&nbsp;Yoichi Kobayashi","doi":"10.12938/bmfh.2021-025","DOIUrl":"https://doi.org/10.12938/bmfh.2021-025","url":null,"abstract":"<p><p>Recent evidence has shown that gut microbiota dysbiosis is associated with development of gestational diabetes mellitus (GDM). However, the gut microbiota composition of non-obese women with GDM, which accounts for a relatively large percentage of Asian GDM, is unknown. We investigated the characteristics of gut microbiota of Japanese pregnant women with GDM. Fecal samples from Japanese pregnant women with GDM (n=20) and normal glucose tolerance (NGT, n=16) were collected at the time of GDM diagnosis (T1), at 35-37 weeks of gestation (T2), and at 4 weeks postpartum (T3). Gut microbiota composition was characterized from fecal DNA by sequencing of 16S rRNA genes. Serum samples were collected late in the third trimester, and the circulating levels of adiponectin and IL-6 were measured by ELISA. At the genus level, <i>Peptostreptococcaceae Romboutsia</i> was enriched in GDM women at T1 (p=0.008) and T2 (p=0.047). The women with lower serum adiponectin tended to have more <i>Romboutsia</i>. The Shannon index was significantly lower in the GDM women at T3 than in the NGT women (p=0.008), and that of the GDM women decreased significantly from T2 to T3 (p=0.02). No significant difference in bacterial community structure was found in a beta diversity analysis. The non-obese GDM women (body mass index <25.0 kg/m²) showed a lower abundance of <i>Coriobacteriaceae Collinsella</i> at T1 (p=0.03) and higher abundance of <i>Akkermansia</i> at T2 (p=0.04) than the normal control. The non-obese GDM women had the distinctive gut microbiota profiles. Analysis of gut microbiota is potentially useful for risk assessment of GDM in non-obese pregnant women.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 1","pages":"4-11"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/05/20/bmfh-41-004.PMC8727054.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39825706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbiota diversity and bacterial load after successful treatment of <i>Clostridioides difficile</i> infection with honey lavage in 4 patients.","authors":"Yara M W VAN Knippenberg,&nbsp;Robert J F Laheij","doi":"10.12938/bmfh.2021-047","DOIUrl":"https://doi.org/10.12938/bmfh.2021-047","url":null,"abstract":"<p><p>In this letter, an experimental therapy in four patients with therapy-resistant <i>Clostridioides difficile</i> infection is described. These four patients were treated with Manuka honey via colon lavage. First, the patients received a three-day fidaxomicin treatment. The colon lavage was performed on the third day. During a subsequent ileocolonoscopy, 300 mL 15% Manuka honey was applied via a spray catheter. Patients remained in bed for two hours after the procedure and did not defecate. The patient's microbiomes were tested before treatment, after the fidaxomicin treatment, and after honey lavage. A decrease in <i>C. difficile</i> load was found in their microbiomes. Additionally, restoration of microbiota diversity after the honey lavage was also noted. The four patients experienced complete cessation of watery stools and remain symptom free. These results indicate the need for more clinical research into this matter.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 1","pages":"1-3"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/18/2e/bmfh-41-001.PMC8727055.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39825705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel shuttle vector pGMβ1 for conjugative chromosomal manipulation of <i>Lactobacillus delbrueckii</i> subsp. <i>bulgaricus</i>.","authors":"Daiki Iwamoto,&nbsp;Megumi Ishizaki,&nbsp;Taiki Miura,&nbsp;Yasuko Sasaki","doi":"10.12938/bmfh.2021-014","DOIUrl":"https://doi.org/10.12938/bmfh.2021-014","url":null,"abstract":"<p><p><i>Lactobacillus delbrueckii</i> subsp. <i>bulgaricus</i> (<i>L. bulgaricus</i>) is widely used as a starter for yogurt and cheese worldwide. Despite the economic importance of this bacterium in the dairy industry, there have been few genetic studies involving knockout or overexpression mutants to identify the functions of <i>L. bulgaricus</i> genes. One of the main reasons for this gap is the low transformation efficiency of available <i>L. bulgaricus</i> chromosome-integrating vectors upon performing conventional electroporation. We previously proposed the conjugal plasmid pAMβ1 as an integration vector for <i>L. bulgaricus</i>, as conjugation could avert the need for a restriction modification system; pAMβ1 does not replicate and integrate into the chromosome of <i>L. bulgaricus.</i> Here, we describe an effective chromosomal manipulation system involving a novel shuttle vector pGMβ1, which could improve the operability of the broad host-range conjugal plasmid pAMβ1. We further developed an enhanced filter-mating method for conjugation. To validate this system, the effectiveness of conversion of the lactate dehydrogenase gene <i>D-ldh</i> of <i>L. bulgaricus</i> to the <i>L-ldh</i> form of <i>Streptococcus thermophilus</i> was examined. As pGMβ1 and pAMβ1 are unable to replicate in <i>L. delbrueckii</i> subsp. <i>delbrueckii</i>, they were chromosomally integrated. However, these plasmids could replicate in <i>L. delbrueckii</i> subsp. <i>indicus</i> and <i>sunkii</i>. This integration system could unearth important gene functions in <i>L. bulgaricus</i> and thus improve its applications in the dairy industry. Moreover, this conjugation system could be used as a stable vector for the transformation of long cluster genes in several species of lactic acid bacteria.</p>","PeriodicalId":8867,"journal":{"name":"Bioscience of Microbiota, Food and Health","volume":"41 1","pages":"20-29"},"PeriodicalIF":3.1,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/21/a2/bmfh-41-020.PMC8727053.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39825708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}