• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.197-201
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• 2004

A 2-D gel protein analysis of Lactobacillus reuteri ATCC 55739 produced spots corresponding to subunits of the pyruvate dehydrogenase complex, as identified by N-terminal protein sequencing. Oligonucleotide probes specific for the subunits of the pyruvate dehydrogenase complex were synthesized ,md used to screen a L. reuteri genomic library to clone the structural genes. Two positive clones were isolated and identified as having the same 2.2 kb insert. A pdhB encoding the $\beta$-subunit of El subunit (pyruvate dehydrogenase component) of the pyruvate dehydrogenase complex was located in the middle of the insert. Furthermore, a 5' truncated pdhA encoding the $\alpha$-subunit of the E1 subunit and a 3' truncated pdhC encoding the E2 subunit (dihydrolipoamide acetyltransferase) were also located upstream and downstream of the pdhB, respectively.

• Clinical and Experimental Pediatrics
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• 제63권12호
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• pp.485-490
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• 2020

Background: Recurrent abdominal pain (RAP) is one of the frequent complaints in general practice, particularly in pediatrics and is among the common cause of referral to gastroenterology clinics. Purpose: This study is designed to investigate the effects of probiotics for the treatment of RAP and desired therapeutic outcomes. Methods: One hundred twenty-five children with the diagnosis of RAP according to Rome III criteria for irritable bowel syndrome (IBS), functional abdominal pain (FAP), functional dyspepsia (FD), and abdominal migraine (AM), were enrolled in this double-blind randomized controlled trial. Results: Sixty-five subjects received probiotics, and others received placebo treatment for 4 weeks. Lactobacillus reuteri was therapeutically effective in 32 patients compared to 8 patients, responding to the placebo treatment. Compared to baseline, all pain-related variables showed a significant reduction for the IBS and FD at the end of the 4th week. However, it did not respond well in FAP and AM groups. Pain-related outcomes such as, frequency of the pain, severity, and duration of the pain were decreased following the probiotic treatment. No therapeutic response was seen in AM group after the administration of probiotics. L. reuteri significantly led to pain relief in the overall population, and also in FAP, FD, and IBS subgroups. Conclusion: L. reuteri probiotics are likely to lead to RAP relief and can be recommended for the treatment of functional gastrointestinal disorders.

• Genomics & Informatics
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• 제17권4호
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• pp.43.1-43.5
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• 2019

Lactobacillus acidophilus UBLA-34, L. paracasei UBLPC-35, L. plantarum UBLP-40, and L. reuteri UBLRU-87 were isolated from different varieties of fermented foods. To determine the probiotic safety at the strain level, the whole genome of the respective strains was sequenced, assembled, and characterized. Both the core-genome and pan-genome phylogeny showed that L. reuteri was closest to L. plantarum than to L. acidophilus, which was closest to L. paracasei. The genomic analysis of all the strains confirmed the absence of genes encoding putative virulence factors, antibiotic resistance, and the plasmids.

• 한국식품과학회지
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• 제36권1호
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• pp.111-115
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• 2004

Lactobacillus reuteri는 혐기적 조건에서 글리세롤을 대사하여 강력한 항균물질인 루테린을 생산한다. 본 연구의 목적은 다양한 조건에서 루테린의 생산성을 비교 연구하는 것이었다. 회분식 배양에서 $32,\;37,\;42^{\circ}C$에서 비교하였을 때 온도가 높을 수록 시간당 생산되는 량은 많았고 생산이 더 빠른 시간내에 둔화되었으며 생산되는 총량이 더 많았다. 다양한 아미노산을 첨가한 상황에서 생산된 루테린 활성을 조사하였을 때 proline을 제외하고 대부분의 아미노산은 루테린 활성을 저하시켰다. 생산된 루테린은 다양한 식중독균의 사멸을 유도하였다. 생산성을 증가시키기 위하여 L. reuteri 세포를 반응기에 현탁시키고 글리세롤 용액을 연속적으로 통과시켰다. 회분식에 비교하여 연속식 공정으로 루테린 생산성은 현저히 증가하였다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제22권6호
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• pp.545-553
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• 2019

Purpose: Feeding tolerance is extremely important in preterm infants. This study aimed to evaluate whether preterm infants receiving Lactobacillus reuteri DSM 17938 would develop fewer symptoms of feeding intolerance. Secondary outcomes were duration of parenteral nutrition, time to reach full feeding, length of hospital stay, sepsis, necrotizing enterocolitis (NEC), diarrhea, and mortality. Methods: This double-blind randomized controlled trial of L. reuteri DSM 17938 versus placebo included 94 neonates with a gestational age of 28-34 weeks and birth weight of 1,000-1,800 g. Results: Feeding intolerance (vomiting and/or distension) was less common in the probiotic group than in the placebo group (8.5% vs. 25.5%; relative risk, 0.33; 95% confidence interval, 0.12-0.96; p=0.03). No significant intergroup differences were found in proven sepsis, time to reach full feeding, length of hospital stay, or diarrhea. The prevalence of NEC (stages 2 and 3) was 6.4% in the placebo group vs. 0% in the probiotic group (relative risk, 1.07; 95% confidence interval, 0.99-1.15; p=0.24). Mortality rates were 2.1% in the probiotic group and 8.5% in the placebo group, p=0.36). Conclusion: The administration of L. reuteri DSM 17938 to preterm infants was safe and significantly reduced feeding intolerance. No significant differences were found in any other secondary outcomes.

• Animal Bioscience
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• 제35권9호
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• pp.1379-1389
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• 2022

Objective: This study identified the major lactic acid bacteria (LAB) strains from different fermented total mixed rations (FTMRs) via metataxonomic analysis and evaluated the ability of their standard strain as ensiling inoculants for corn stover silage. Methods: The bacterial composition of eight FTMRs were analyzed by 16S rDNA sequencing. Corn stover was ensiled without LAB inoculation (control) or with 1×10⁶ cfu/g LAB standard strain (Lactobacillus vaginalis, Lactobacillus reuteri, Lactobacillus helveticus, or Lactobacillus paralimentarius) selected from the FTMRs or 10 g/t commercial silage inoculant (CSI) around 25℃ for 56 days. For each inoculation, a portion of the silage was sampled to analyze ensiling characteristics at time intervals of 0, 1, 3, 7, 14, 28, and 56 days, gas production (GP), microbial crude protein and volatile fatty acids as the measurements of rumen fermentation characteristics were evaluated in vitro with the silages of 56 days after 72 h incubation. Results: Lactobacillus covered >85% relative abundance of all FTMRs, in which L. pontis, L. vaginalis, L. reuteri, L. helveticus, and L. paralimentarius showed >4% in specific FTMRs. CSI, L. helveticus, and L. paralimentarius accelerated the decline of silage pH. Silage inoculated with L. paralimentarius and CSI produced more lactic acid the early 14 days. Silage inoculated with L. paralimentarius produced less acetic acid and butyric acid. For the in vitro rumen fermentation, silage inoculated with CSI produced more potential GP, isobutyric acid, and isovaleric acid; silage inoculated with L. helveticus produced more potential GP and isovaleric acid, silage inoculated with L. paralimentarius or L. reuteri produced more potential GP only. Conclusion: The standard strain L. paralimentarius (DSM 13238) is a promising ensiling inoculant for corn stover silage. The findings provide clues on strategies to select LAB to improve the quality of silage.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1178-1182
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• 2005

Survival of thermotolerant Lactobacillus reuteri KUB-AC5 in $20\%$ (w/v) skim milk was found to be $11.3\%$ after spray drying by using a pilot scale spray dryer with inlet temperature at $170^{\circ}C$ and outlet temperature at $85^{\circ}C$. The ability of dried cell to produce antimicrobial activity was not affected by the spray drying. The model system for predicting viability of spray-dried L. reuteri KUB-AC5 during long-term storage was established, based on the Arrhenius equation, and verified by experimental data, because the viability of cells during storage can be correlated with storage temperature. The viability during storage at $30^{\circ}C$ declined more rapidly than that storage at $4^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• 제21권9호
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• pp.1324-1329
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• 2008

This study was conducted to evaluate the potential of the transformed Lactobacillus reuteri Pg4 (T-Pg4) harboring the ${\beta}$-glucanase gene as a poultry probiotic. The probiotic properties of the T-Pg4 strain were evaluated in vitro by their adherence capability and acid and bile salt tolerance, and were evaluated in vivo by their survival and adhesion in the gastrointestinal tract (GIT) of specific-pathogen-free (SPF) chickens. The results showed that the T-Pg4 strain exhibited resistance to acidic conditions and contact with bile salt, and adhered efficiently to the crop and intestinal epithelial cells of chickens in vitro. The T-Pg4 strain also could survive and colonize the gastrointestinal epithelium of the experimental SPF chickens in vivo. In addition, radial enzyme diffusion was used to demonstrate that the Lactobacillus spp. randomly isolated from the GIT of the SPF chickens fed T-Pg4 possessed ${\beta}$-glucanase secretion capability. These findings have demonstrated that the transformed L. reuteri Pg4 survives transit through the stomach and intestine, and may secrete ${\beta}$-glucanase in the chicken GIT. Therefore, it is suggested that this organism could be used as a multifunctional poultry probiotic.

• Journal of Microbiology and Biotechnology
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• 제26권6호
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• pp.1018-1025
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• 2016

Probiotics are considered as the best effective alternatives to antibiotics. The aim of this study was to characterize the probiotic potential of lactobacilli for use in swine farming by using in vitro evaluation methods. A total of 106 lactic acid bacterial isolates, originating from porcine feces, were first screened for the capacity to survive stresses considered important for putative probiotic strains. Sixteen isolates showed notable acid and bile resistance, antibacterial activity, and adherence to intestinal porcine epithelial cells (IPEC-1). One isolate, LR1, identified as Lactobacillus reuteri, was selected for extensive study of its probiotic and functional properties in IPEC-1 cell models. L. reuteri LR1 exhibited good adhesion to IPEC-1 cells and could inhibit the adhesion of enterotoxigenic Escherichia coli (ETEC) to IPEC-1 cells. L. reuteri LR1 could also modulate transcript and protein expression of cytokines involved in inflammation in IPEC-1 cells; the Lactobacillus strain inhibited the ETEC-induced expression of proinflammatory transcripts (IL-6 and TNF-α) and protein (IL-6), and increased the level of anti-inflammatory cytokine (IL-10). Measurement of the permeation of FD-4 showed that L. reuteri LR1 could maintain barrier integrity in monolayer IPEC-1 cells exposed to ETEC. Immunolocalization experiments showed L. reuteri LR1 could also prevent ETEC-induced tight junction ZO-1 disruption. Together, these results indicate that L. reuteri LR1 exhibits desirable probiotic properties and could be a potential probiotic for use in swine production.

• Journal of Microbiology and Biotechnology
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• 제15권3호
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• pp.525-531
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• 2005

From a genomic library of Lactobacillus reuteri ATCC 55739, one clone, NE347, carrying a pyrH gene encoding UMP kinase, was identified. pNE347 carried a 1.88 kb EcoRI fragment and the pyrH was located in the middle of the insert. pyrH ORF was 723 bp in size and capable of encoding UMP kinase composed of 240 amino acid residues. tsf encoding an elongation factor-Ts and frr encoding a ribosomal recycling factor were present upstream and downstream of pyrH, respectively. When introduced into E. coli KUR1244, a pyrH-negative strain, pNE347 restored the ability to grow at $42^{\circ}C$, indicating that pyrH from L. reuteri synthesized functional UMP kinase in E. coli. Northern blot experiment showed that pyrH and frr were cotranscribed as a 1.4 kb single transcript. pyrH was overexpressed in E. coli by using a pET26b(+) vector, and a major 25 kDa protein band appeared on SDS-polyacrylamide gel.