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1.
Artículo en Inglés | MEDLINE | ID: mdl-38536087

RESUMEN

A Gram-stain-positive, non-spore-forming, and obligate anaerobic bacteria designated strain CBA3647T was isolated from a horse faecal sample in Jeju, Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain CBA3647T formed a distinct phyletic lineage from closely related species within the genus Peptostreptococcus. Based on comparative analysis of 16S rRNA gene sequences, Peptostreptococcus anaerobius ATCC 27337T is most closely related to strain CBA3647T with a 16S rRNA gene similarity of 98.31 %, while similarity to other type strains is below 98.0 %. The genomic DNA G+C content of strain CBA3647T was 30.0 mol%. The digital DNA-DNA hybridization values between strain CBA3647T and the six Peptostreptococcus species were equal to or less than 24 %. Cells were non-motile and oval-shaped cocci with catalase-positive and oxidase-negative activities. Growth occurred at 20-40 °C (optimum, 35 °C), pH 6-8 (optimum, pH 7), and in the presence of 0-2 % (w/v) NaCl (optimum, 1 %). Strain CBA3647T contained C14 : 0 iso and C16 : 0 as major fatty acids. Phenotypic, chemotaxonomic, and molecular properties of strain CBA3647T suggest that it represents a novel species in the genus Peptostreptococcus, which has been named Peptostreptococcus equinus sp. nov. The type strain is CBA3647T (=KACC 22891T= JCM 35846T).


Asunto(s)
Ácidos Grasos , Peptostreptococcus , Animales , Caballos , Composición de Base , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Heces
2.
Thorax ; 78(11): 1080-1089, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37495367

RESUMEN

BACKGROUND: Diet has a crucial role in the gut microbiota, and dysbiosis in the gut and lungs has been suggested to be associated with chronic obstructive pulmonary disease. We compared the diet, microbiome and metabolome between asymptomatic smokers and those with emphysema. METHODS: We enrolled 10 asymptomatic smokers with preserved lung function and 16 smokers with emphysema with severe airflow limitation. Dietary intake information was gathered by a self-reported questionnaire. Sputum and faecal samples were collected for microbial and metabolomics analysis. A murine model of emphysema was used to determine the effect of metabolite supplementation. RESULTS: Despite having a similar smoking history with emphysema patients, asymptomatic smokers had higher values of body mass index, fibre intake and faecal acetate level. Linear discriminant analysis identified 17 microbial taxonomic members that were relatively enriched in the faeces of asymptomatic smokers. Analysis of similarity results showed dissimilarity between the two groups (r=0.287, p=0.003). Higher acetate level was positively associated with forced expiratory volume in one second in the emphysema group (r=0.628, p=0.012). Asymptomatic smokers had a greater number of species associated with acetate and propionate (r>0.6) than did those with emphysema (30 vs 19). In an emphysema mouse model, supplementation of acetate and propionate reduced alveolar destruction and the production of proinflammatory cytokines, and propionate decreased the CD3+CD4+IL-17+ T-cell population in the lung and spleen. CONCLUSION: Smokers with emphysema showed differences in diet, microbiome and short-chain fatty acids compared with asymptomatic smokers. Acetate and propionate showed therapeutic effects in a smoking-induced murine model of emphysema.


Asunto(s)
Enfisema , Microbioma Gastrointestinal , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Animales , Ratones , Fumadores , Propionatos , Modelos Animales de Enfermedad , Volumen Espiratorio Forzado , Enfisema/complicaciones , Acetatos
3.
Radiology ; 307(2): e221488, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36786699

RESUMEN

Background Low-dose chest CT screening is recommended for smokers with the potential for lung function abnormality, but its role in predicting lung function remains unclear. Purpose To develop a deep learning algorithm to predict pulmonary function with low-dose CT images in participants using health screening services. Materials and Methods In this retrospective study, participants underwent health screening with same-day low-dose CT and pulmonary function testing with spirometry at a university affiliated tertiary referral general hospital between January 2015 and December 2018. The data set was split into a development set (model training, validation, and internal test sets) and temporally independent test set according to first visit year. A convolutional neural network was trained to predict the forced expiratory volume in the first second of expiration (FEV1) and forced vital capacity (FVC) from low-dose CT. The mean absolute error and concordance correlation coefficient (CCC) were used to evaluate agreement between spirometry as the reference standard and deep-learning prediction as the index test. FVC and FEV1 percent predicted (hereafter, FVC% and FEV1%) values less than 80% and percent of FVC exhaled in first second (hereafter, FEV1/FVC) less than 70% were used to classify participants at high risk. Results A total of 16 148 participants were included (mean age, 55 years ± 10 [SD]; 10 981 men) and divided into a development set (n = 13 428) and temporally independent test set (n = 2720). In the temporally independent test set, the mean absolute error and CCC were 0.22 L and 0.94, respectively, for FVC and 0.22 L and 0.91 for FEV1. For the prediction of the respiratory high-risk group, FVC%, FEV1%, and FEV1/FVC had respective accuracies of 89.6% (2436 of 2720 participants; 95% CI: 88.4, 90.7), 85.9% (2337 of 2720 participants; 95% CI: 84.6, 87.2), and 90.2% (2453 of 2720 participants; 95% CI: 89.1, 91.3) in the same testing data set. The sensitivities were 61.6% (242 of 393 participants; 95% CI: 59.7, 63.4), 46.9% (226 of 482 participants; 95% CI: 45.0, 48.8), and 36.1% (91 of 252 participants; 95% CI: 34.3, 37.9), respectively. Conclusion A deep learning model applied to volumetric chest CT predicted pulmonary function with relatively good performance. © RSNA, 2023 Supplemental material is available for this article.


Asunto(s)
Aprendizaje Profundo , Masculino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Pulmón/diagnóstico por imagen , Capacidad Vital , Volumen Espiratorio Forzado , Espirometría/métodos , Tomografía Computarizada por Rayos X
4.
Crit Rev Food Sci Nutr ; : 1-14, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36718547

RESUMEN

Kimchi is a traditional fermented vegetable side dish in Korea and has become a global health food. Kimchi undergoes spontaneous fermentation, mainly by lactic acid bacteria (LAB) originating from its raw ingredients. Numerous LAB, including the genera Leuconostoc, Weissella, and Lactobacillus, participate in kimchi fermentation, reaching approximately 9-10 log colony forming units per gram or milliliter of food. The several health benefits of LAB (e.g., antioxidant and anti-inflammatory properties) combined with their probiotic potential in complex diseases including obesity, cancer, atopic dermatitis, and immunomodulatory effect have generated an interest in the health effects of LAB present in kimchi. In order to estimate the potential of kimchi as a probiotic food, we comprehensively surveyed the health functionalities of kimchi and kimchi LAB, and their effects on human gut environment, highlighting the probiotics function.

5.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37910171

RESUMEN

Strain CBA3108T is a Gram-positive, non-spore-forming, obligately anaerobic bacterium isolated from horse faecal samples obtained in Jeju Island, Republic of Korea. The cells of CBA3108T are non-motile short rods that have been assessed as catalase-positive and oxidase-negative. Growth of the strain occurs under the following conditions: 25-45 °C (optimum, 35 °C); pH 6-9 (optimum, pH 6); and in the presence of 0-6 % (w/v) NaCl (optimum, 2%). Major fatty acids in the strain include C15 : 0 iso and C15 : 0 iso DMA, while major polar lipids include phosphatidylglycerol, diphosphatidylglycerol and phosphatidylcholine. Based on phylogenetic analysis using 16S rRNA gene sequences, strain CBA3108T forms a phyletic lineage distinct from other closely related species within the genus Cutibacterium. It was found to be most closely related to Cutibacterium avidum ATCC 25577T (98.27 % 16S rRNA gene sequence similarity) and other strains within the genus (≤98.0 %). The genomic DNA G+C content of strain CBA3108T was 63.2 mol%. The in silico DNA-DNA hybridization values of strain CBA3108T with C. avidum ATCC 25577T, C. porci WCA-380-WT-3AT and C. acnes subsp. acnes DSM 1897T were 33.6, 21.7 and 22.7 %, respectively. Its phenotypic, chemotaxonomic and molecular properties support the hypothesis that strain CBA3108T represents a novel species in the genus Cutibacterium, for which we propose the name Cutibacterium equinum sp. nov. The type strain is CBA3108T (=KACC 22889T=JCM 35966T).


Asunto(s)
Ácidos Grasos , Animales , Caballos , Composición de Base , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Heces
6.
Artículo en Inglés | MEDLINE | ID: mdl-37750780

RESUMEN

A novel, anaerobic, Gram-stain-positive coccoid strain, CBA3646T, was isolated from the faeces of a thoroughbred racehorse. Phylogenetic analysis based on 16S rRNA gene sequencing yielded results indicative of CBA3646T representing a member of the genus Peptoniphilus, with the species most closely related to it being Peptoniphilus asaccharolyticus DSM 20463T, with a similarity of 94.79 %. DNA-DNA relatedness and average nucleotide identity values between CBA3646T and P. asaccharolyticus DSM 20463T were 21.4 and 67.6 %, respectively. CBA3646T has a circular chromosomal genome of 1 709 189 bp (45.5 mol% DNA G+C content), containing 1652 genes in total, 1584 predicted protein-coding genes, 3 complete rRNA loci and 47 tRNA genes. The cells were non-motile diplococci, catalase-positive and oxidase-negative. Growth of CBA3646T was observed at 20-40 °C (optimal temperature, 35 °C) and in the presence of 0-4 % (w/v) NaCl (optimum concentration, 1 %). The major fatty acids (>10 %) of CBA3646T were C16 : 0, C18 : 1ω9c and C18 : 1ω9c dimethyl acetal, with its major polar lipids being diphosphatidylglycerol and phosphatidylglycerol. The elucidated phylogenetic, physiological, chemotaxonomic and molecular properties are indicative of strain CBA3646T representing a novel species of the genus Peptoniphilus, or which the name Peptoniphilus equinus sp. nov. is proposed. The type strain is CBA3646T (= KACC 22890T = JCM 35845T).


Asunto(s)
Colorantes , Cocos Grampositivos , Caballos , Animales , Anaerobiosis , Composición de Base , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Heces , Clostridiales
7.
Biochem Biophys Res Commun ; 619: 110-116, 2022 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-35753218

RESUMEN

Chemotherapy induces tumor cell death and inhibits tumor progression, but the accompanying immune responses in the surrounding dying tissue cause significant inflammation. These responses, such as excessive neutrophil infiltration into tumor tissue, are the main causes of resistance to anticancer treatment. The development of drugs that reduce neutrophil infiltration into tumors is necessary to increase the anticancer effect of chemotherapy. Here, we show that the antitumor effect of the chemotherapy AC regimen (Adriamycin and cyclophosphamide) was increased by 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) cotreatment in the MDA-MB-231 triple-negative breast cancer xenograft mouse model. Tumor growth was inhibited up to 56% in mice treated with AC and inhibited up to 94% in mice cotreated with AC and PLAG. Side effects of chemotherapy, such as a reduction in body weight, were alleviated in mice cotreated with AC and PLAG. Excessive neutrophil infiltration caused by the AC regimen was successfully cleared in mice cotreated with AC and PLAG. We conclude that PLAG inhibits excessive neutrophil infiltration that aids tumor growth. Reduced neutrophils and increased lymphocytes in PLAG-treated mice can maximize the antitumor effect of the AC regimen and inhibit tumor growth.


Asunto(s)
Doxorrubicina , Neoplasias de la Mama Triple Negativas , Animales , Línea Celular Tumoral , Ciclofosfamida/uso terapéutico , Modelos Animales de Enfermedad , Doxorrubicina/uso terapéutico , Xenoinjertos , Humanos , Ratones , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Ensayos Antitumor por Modelo de Xenoinjerto
8.
BMC Cancer ; 22(1): 727, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35787261

RESUMEN

BACKGROUND: The PD-L1 antibody is an immune checkpoint inhibitor (ICI) attracting attention. The third-generation anticancer drug has been proven to be very effective due to fewer side effects and higher tumor-specific reactions than conventional anticancer drugs. However, as tumors produce additional resistance in the host immune system, the effectiveness of ICI is gradually weakening. Therefore, it is very important to develop a combination therapy that increases the anticancer effect of ICI by removing anticancer resistance factors present around the tumor. METHODS: The syngeneic model was used (n = 6) to investigate the enhanced anti-tumor effect of PD-L1 antibody with the addition of PLAG. MB49 murine urothelial cancer cells were implanted into the C57BL/6 mice subcutaneously. PLAG at different dosages (50/100 mpk) was daily administered orally for another 4 weeks with or without 5 mpk PD-L1 antibody (10F.9G2). PD-L1 antibody was delivered via IP injection once a week. RESULTS: The aPD-L1 monotherapy group inhibited tumor growth of 56% compared to the positive group, while the PLAG and aPD-L1 co-treatment inhibited by 89%. PLAG treatment effectively reduced neutrophils infiltrating localized in tumor and converted to a tumor microenvironment with anti-tumor effective T-cells. PLAG increased tumor infiltration of CD8 positive cytotoxic T-cell populations while effectively inhibiting the infiltration of neoplastic T-cells such as CD4/FoxP3. Eventually, neutrophil-induced tumor ICI resistance was resolved by restoring the neutrophil-to-lymphocyte ratio to the normal range. In addition, regulation of cytokine and chemokine factors that inhibit neutrophil infiltration and increase the killing activity of cytotoxic T cells was observed in the tumors of mice treated with PLAG + aPD-L1. CONCLUSIONS: PLAG effectively turned the tumor-promoting microenvironment into a tumor-suppressing microenvironment. As a molecule that increases the anti-tumor effectiveness of aPD-L1, PLAG has the potential to be an essential and effective ICI co-therapeutic agent.


Asunto(s)
Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Animales , Ratones , Antígeno B7-H1 , Carcinoma de Células Transicionales/tratamiento farmacológico , Ratones Endogámicos C57BL , Infiltración Neutrófila , Microambiente Tumoral , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
9.
J Obstet Gynaecol ; 42(5): 1482-1488, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34996320

RESUMEN

The vaginal microbiome has been widely investigated. However, its relationship with impaired ovarian function has not been evaluated. We conducted a next-generation sequencing (NGS) study of the vaginal microbiome in females with normal and decreased ovarian function and analysed its sensitivity to environmental pollutants. Vaginal swabs were collected from 92 individuals (22 with impaired ovarian function). The 16S rDNA sequences were assembled by FLASH and clustered in OTUs. Diversity analysis was performed using QIIME. The impaired function group showed lower AMH (p < .01) and higher FSH (p = .04). Only two species showed significant differences: Propionibacterium acnes and Prevotella copri. Moreover, more environmental pollutants were related to changes in the vaginal microbiome in the impaired ovarian function group than in the normal group. Vaginal microbiomes in young women with decreased ovarian function tended to be more sensitive to environmental pollutants, especially volatile organic compounds.Impact StatementWhat is already known on this subject? In this study, the possible influence of environmental pollutants, especially volatile organic compounds to ovarian function were identified via next-generation sequencing.What do the results of this study add? This is the first study that shows vaginal microbiomes in young women with decreased ovarian function to be more sensitive to environmental pollutants.What are the implications of these findings for clinical practice and/or further research? The association between impaired ovarian function and environmental pollutants from this study could be helpful when counselling patients with POI.


Asunto(s)
Contaminantes Ambientales , Microbiota , Compuestos Orgánicos Volátiles , Contaminantes Ambientales/efectos adversos , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Microbiota/genética , ARN Ribosómico 16S/genética , Vagina/microbiología
10.
Arch Microbiol ; 203(1): 261-268, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32918097

RESUMEN

Extremely halophilic archaea (haloarchaea) belonging to the phylum Euryarchaeota have been found in high-salinity environments. In this study, Halarchaeum sp. CBA1220, Halorubrum sp. CBA1229, and Halolamina sp. CBA1230, which are facultatively oligotrophic haloarchaea, were isolated from solar salt by culture under oligotrophic culture conditions. The complete genomes of strains CBA1220, CBA1229, and CBA1230 were sequenced and were found to contain 3,175,875, 3,582,278, and 3,465,332 bp, with a G + C content of 68.25, 67.66, and 66.75 mol %, respectively. In total, 60, 36, and 33 carbohydrate-active enzyme genes were determined in the respective strains. The strains harbored various genes encoding stress-tolerance proteins, including universal stress proteins, cold-shock proteins, and rubrerythrin and rubrerythrin-related proteins. The genome data produced in this study will facilitate further research to improve our understanding of other halophilic strains and promote their industrial application.


Asunto(s)
Euryarchaeota/genética , Genoma Arqueal/genética , Composición de Base , Genómica , Halobacteriaceae/clasificación , Halobacteriaceae/genética , Halorubrum/clasificación , Halorubrum/genética , Salinidad , Estrés Fisiológico/genética
11.
Arch Microbiol ; 203(6): 3163-3169, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33821299

RESUMEN

In this study, aimed at investigating and characterizing river sediment bacteria, we isolated a Gram-stain-positive, rod-shaped, obligate anaerobic bacterium, strain CBA3637T, from the sediment of the Geum River. This strain grew at 10-40 °C (optimum, 30 °C), 0-1% NaCl (optimum, 0%), and pH 7-8 (optimum, pH 7). The 16S rRNA gene sequence comparison revealed Aminipila butyrica DSM 103574T to be the closest relative of strain CBA3637T (96.6-96.7% similarity); and both strains clustered together in phylogenetic analysis. The genome of strain CBA3637T was found to consist of a single chromosome (3.51 Mbp; 36.98% G + C content). Comparative genomic analysis of the strain CBA3637T with A. butyrica DSM 103574T revealed that strain CBA3637T possessed five unique pathways related to polyamine biosynthesis, lipopolysaccharide metabolism, pyrimidine metabolism, and cofactor and vitamin metabolism. Strain CBA3637T contained C14:0, C16:0, and C18:1 ω9c as the major fatty acids, and diphosphatidylglycerol as the major polar lipid. No respiratory quinone was observed. Biochemical, chemotaxonomic, and genotypic data revealed that the strain CBA3637T is a representative of a novel species within the genus Aminipila, for which the name Aminipila terrae is proposed. The type strain is CBA3637T (= KACC 21651T = DSM 110662T).


Asunto(s)
Clostridiales , Sedimentos Geológicos , Fosfolípidos , Ríos , Anaerobiosis , Composición de Base , Clostridiales/clasificación , Clostridiales/genética , Clostridiales/aislamiento & purificación , Ácidos Grasos/análisis , Sedimentos Geológicos/microbiología , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S/genética , Ríos/microbiología
12.
Antonie Van Leeuwenhoek ; 114(5): 507-513, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33730291

RESUMEN

Strain CBA3638T was isolated from the Geum River sediment, Republic of Korea. The cells of strain CBA3638T were Gram-stain-positive, strictly anaerobic, rod-shaped, and 0.5-1.0 µm wide, and 4.0-4.5 µm long. Optimal growth occurred at 37 °C, pH 7.0, and 1.0% (w/v) NaCl. Based on the 16S rRNA gene sequence, the phylogenetic analysis showed that strain CBA3638T belongs to the genus Anaerocolumna in the family Lachnospiraceae, and is most closely related to Anaerocolumna cellulosilytica (94.6-95.0%). The DDH value with A. cellulosilytica SN021T showed 15.0% relatedness. The genome of strain CBA3638T consisted of one circular chromosome that is 5,500,435 bp long with a 36.7 mol% G + C content. The genome contained seven 16S-5S-23S rRNA operons and one antibiotic resistance-related transporter gene (mefA). Quinones were not detected. The predominant cellular fatty acids were C16:0 and C14:0 and the polar lipids were diphosphatidylglycerol, phosphatidylcholine, and uncharacterised polar lipids. Based on the polyphasic taxonomic analysis, we propose strain CBA3638T as a novel species in the genus Anaerocolumna, with the name Anaerocolumna sedimenticola sp. nov. The type strain is CBA3638T (= KACC 21652T = DSM 110663T).


Asunto(s)
Agua Dulce , Fosfolípidos , Técnicas de Tipificación Bacteriana , Composición de Base , Clostridiales , ADN Bacteriano/genética , Ácidos Grasos/análisis , Fosfolípidos/análisis , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
13.
Mikrochim Acta ; 188(10): 333, 2021 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-34498149

RESUMEN

Nucleic acid amplification tests (NAATs) are powerful tools for the Japanese encephalitis virus (JEV). We demonstrated highly sensitive, specific, and rapid detection of JEV by colorimetric reverse-transcription loop-mediated isothermal amplification (cRT-LAMP). Under optimized conditions, the RT-LAMP assay results showed that the limit of detection was approximately equivalent to 1 RNA genome copy/µL with an assay time of 30 min. The assay was highly specific to JEV when tested with other mosquito-borne virus panels (Zika virus and dengue virus types 2-4). The ability to detect JEV directly from crude human sample matrices (serum and urine) demonstrated the suitability of our JEV RT-LAMP for widespread clinical application. The JEV RT-LAMP provides combination of  rapid colorimetric determination of true-positive JEV RT-LAMP amplicons with our recently developed JEV-nanobarcodes, measured at absorbance wavelenght of 530 (A530) and 650 (A650), which have a limit of detection of 23.3 ng/µL. The AuNP:polyA10-JEV RT-LAMP nanobarcodes exhibited superior capability for stabilizing the true-positive JEV RT-LAMP amplicons against salt-induced AuNP aggregation, which improved the evaluation of true/false positive signals in the assay. These advances enable to expand the use of RT-LAMP for point-of-care tests, which will greatly bolster JEV clinical programs. The JEV RT-LAMP nanobarcode assay targeting the envelope (E) gene and MgSO4 induced AuNP aggregation, indicated by an instant pink-to-violet colorimetric read-out.


Asunto(s)
Colorimetría/métodos , Virus de la Encefalitis Japonesa (Especie)/química , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN Viral/análisis , Animales , Secuencia de Bases , Sangre/virología , Oro/química , Humanos , Ácidos Nucleicos Inmovilizados/química , Límite de Detección , Nanopartículas del Metal/química , Poli A/química , ARN Viral/sangre , ARN Viral/orina , Porcinos , Orina/virología
14.
BMC Microbiol ; 20(1): 136, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32460704

RESUMEN

BACKGROUND: Lactococcus members belonging to lactic acid bacteria are widely used as starter bacteria in the production of fermented dairy products. From kimchi, a Korean food made of fermented vegetables, Lactococcus raffinolactis WiKim0068 was isolated and its genome was analyzed. RESULTS: The complete genome of the strain WiKim0068 consists of one chromosome and two plasmids that comprises 2,292,235 bp, with a G + C content of 39.7 mol%. Analysis of orthoANI values among Lactococcus genome sequences showed that the strain WiKim0068 has > 67% sequence similarity to other species and subspecies. In addition, it displayed no antibiotic resistance and can metabolize nicotinate and nicotinamide (vitamin B3). CONCLUSION: These results augments our understanding of the genus Lactococcus and suggest that this new strain has potential industrial applications.


Asunto(s)
Lactococcus/clasificación , Verduras/microbiología , Secuenciación Completa del Genoma/métodos , Composición de Base , Fermentación , Tamaño del Genoma , Genoma Bacteriano , Lactococcus/aislamiento & purificación , Lactococcus/fisiología , Niacina/metabolismo , Niacinamida/metabolismo , Filogenia , Probióticos/análisis
15.
Int J Syst Evol Microbiol ; 70(7): 4298-4304, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32589569

RESUMEN

A novel, facultatively anaerobic actinobacterium, designated strain CBA3103T, was isolated from sediment of the Geum River in South Korea. Phylogenetic analysis indicated that strain CBA3103T is most closely related to Raineyella antarctica LZ-22T (98.47 % 16S rRNA gene sequence similarity). The genome of strain CBA3103T was 3 649 865 bp with a DNA G+C content of 69.6 mol%. The average nucleotide identity value between strain CBA3103T and R. antarctica LZ-22T was 79.22 %. Cells of strain CBA3103T were Gram-positive, rod-shaped, 0.6-0.9 µm wide and 1.4-2.4 µm long. Growth occurred at 15-40 °C (optimum, 35 °C), at pH 6.0-7.0 (optimum, pH 7.0) and with 0-2 % NaCl (w/v) (optimum, 0-1 %, w/v). The major cellular fatty acids in strain CBA3103T were anteiso-C15 : 0, anteiso-C15 : 1 A and iso-C14 : 0. The major respiratory quinone was menaquinone-9(H4). The polar lipids of strain CBA3103T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, five unidentified glycolipids and three unidentified phospholipids. Based on the genotypic, phenotypic and chemotaxonomic analyses, strain CBA3103T represents a novel species of the genus Raineyella, for which the name Raineyella fluvialis sp. nov. (type strain CBA3103T=KACC 21446T=DSM 110288T) is proposed.


Asunto(s)
Sedimentos Geológicos , Filogenia , Propionibacteriaceae/clasificación , Ríos/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Glucolípidos/química , Fosfolípidos/química , Propionibacteriaceae/aislamiento & purificación , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
Appl Microbiol Biotechnol ; 104(18): 7731-7744, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32749526

RESUMEN

Kimchi is a traditional Korean fermented food prepared via spontaneous fermentation by various microorganisms originating from vegetables such as kimchi cabbage, radishes, and garlic. Recent advances in meta-omics approaches that integrate metataxonomics, metagenomics, metatranscriptomics, and metabolomics have contributed to explaining and understanding food fermentation processes. Kimchi microbial communities are composed of majorly lactic acid bacteria such as Leuconostoc, Lactobacillus, and Weissella and fewer eukaryotic microorganisms and kimchi fermentation are accomplished by complex microbial metabolisms to produce diverse metabolites such as lactate, acetate, CO2, ethanol, mannitol, amino acids, formate, malate, diacetyl, acetoin, and 2, 3-butanediol, which determine taste, quality, health benefit, and safety of fermented kimchi products. Therefore, in the future, kimchi researches should be systematically performed using the meta-omics approaches to understand complex microbial metabolisms during kimchi fermentation. KEY POINTS: • Spontaneous fermentation by raw material microbes gives kimchi its unique flavor. • The kimchi microbiome is altered by environmental factors and raw materials. • Through the multi-omics approaches, it is possible to accurately analyze the diversity and metabolic characteristics of kimchi microbiome and discover potential functionalities.


Asunto(s)
Alimentos Fermentados , Weissella , Fermentación , Microbiología de Alimentos , Leuconostoc , Weissella/genética
17.
Food Microbiol ; 86: 103341, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31703875

RESUMEN

The genomic and metabolic features of Lactobacillus sakei were investigated using its pan-genome and by analyzing the metatranscriptome of kimchi fermentation. In the genome-based relatedness analysis, the strains were divided into the Lb. sakei ssp. sakei and Lb. sakei ssp. carnosus lineage groups. Genomic and metabolic pathway analysis revealed that all Lb. sakei strains have the capability of producing d/l-lactate, ethanol, acetate, CO2, formate, l-malate, diacetyl, acetoin, and 2,3-butanediol from d-glucose, d-fructose, d-galactose, sucrose, d-lactose, l-arabinose, cellobiose, d-mannose, d-gluconate, and d-ribose through homolactic and heterolactic fermentation, whereas their capability of d-maltose, d-xylose, l-xylulose, d-galacturonate, and d-glucuronate metabolism is strain-specific. All strains carry genes for the biosynthesis of folate and thiamine, whereas genes for biogenic amine and toxin production, hemolysis, and antibiotic resistance were not identified. The metatranscriptomic analysis showed that the expression of Lb. sakei transcripts involved in carbohydrate metabolism increased as kimchi fermentation progressed, suggesting that Lb. sakei is more competitive during late fermentation stage. Homolactic fermentation pathway was highly expressed and generally constant during kimchi fermentation, whereas expression of heterolactic fermentation pathway increased gradually as fermentation progressed. l-Lactate dehydrogenase was more highly expressed than d-lactate dehydrogenase, suggesting that l-lactate is the major lactate metabolized by Lb. sakei.


Asunto(s)
Brassica/microbiología , Genoma Bacteriano , Latilactobacillus sakei/genética , Latilactobacillus sakei/metabolismo , Verduras/microbiología , Aminas Biogénicas/metabolismo , Fermentación , Alimentos Fermentados/microbiología , Microbiología de Alimentos , Perfilación de la Expresión Génica , Genómica , Ácido Glucurónico/metabolismo , Ácido Láctico/metabolismo , Latilactobacillus sakei/aislamiento & purificación , Redes y Vías Metabólicas
18.
Angew Chem Int Ed Engl ; 59(46): 20385-20389, 2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-32722860

RESUMEN

All-solid-state lithium ion batteries (LIBs) are ideal for energy storage given their safety and long-term stability. However, there is a limited availability of viable electrode active materials. Herein, we report a truxenone-based covalent organic framework (COF-TRO) as cathode materials for all-solid-state LIBs. The high-density carbonyl groups combined with the ordered crystalline COF structure greatly facilitate lithium ion storage via reversible redox reactions. As a result, a high specific capacity of 268 mAh g-1 , almost 97.5 % of the calculated theoretical capacity was achieved. To the best of our knowledge, this is the highest capacity among all COF-based cathode materials for all-solid-state LIBs reported so far. Moreover, the excellent cycling stability (99.9 % capacity retention after 100 cycles at 0.1 C rate) shown by COF-TRO suggests such truxenone-based COFs have great potential in energy storage applications.

19.
J Am Chem Soc ; 141(18): 7518-7525, 2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-30986353

RESUMEN

Ionic covalent organic frameworks (ICOFs) have recently emerged as promising candidates for solid-state electrolytes. Herein, we report the first example of a series of crystalline imidazolate-containing ICOFs as single-ion conducting COF solid electrolyte materials, where lithium cations freely travel through the intrinsic channels with outstanding ion conductivity (up to 7.2 × 10-3 S cm-1) and impressively low activation energy (as low as 0.10 eV). These properties are attributed to the weak Li ion-imidazolate binding interactions and well-defined porous 2D framework structures of such ICOFs. We also investigated the structure-property relationship by varying the electronic properties of substituents (electron donating/withdrawing) that covalently attached to the imidazolate groups. We found electron-withdrawing substituents significantly improve the ion-conducting ability of imidazolate-ICOF by weakening ion-pair interactions. Our study provides a convenient bottom-up approach toward a novel class of highly efficient single-ion conducting ICOFs which could be used in all solid-state electrolytic devices.

20.
Respir Res ; 20(1): 62, 2019 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-30922302

RESUMEN

BACKGROUND: This cohort study of patients with chronic obstructive pulmonary disease (COPD) was performed to evaluate the status of inhaled corticosteroid (ICS) prescriptions following the 2017 revision of the Global Initiative for Chronic Obstructive Lung Disease guidelines. METHODS: A total of 1144 patients from the Korean Obstructive Lung Disease and Korea Chronic Obstructive Pulmonary Disorders Subgroup Study cohorts, with final follow-up visits completed between 2017 and 2018, were analyzed. Features indicative of ICS usage were as follows: a history of asthma, blood eosinophils of ≥300 cells/µl, or ≥ 2 exacerbations in the year prior to enrollment. Among baseline ICS users, we compared annual total and severe exacerbation rates, based on ICS continuation or withdrawal. RESULTS: ICS-containing regimens were prescribed to 46.3% of the enrolled of patients in 2014; this decreased to 38.8% in 2017, and long-acting dual bronchodilators were used instead. Among ICS users in 2017, 47.5% did not exhibit features indicative of ICS usage; 478 used ICS at baseline, and ICS was withdrawn in 77 (16.1%) during the study period. The proportion of patients with asthma and the baseline annual exacerbation rate were greater in the ICS withdrawal groinup than in the ICS continued group (56.6% vs. 41%, p = 0.01; 0.79 vs. 0.53, p < 0.001). Annual exacerbation rates during the follow-up period were similar between the ICS-withdrawal and ICS -continued groups (0.48 vs. 0.47, p = 0.84); however, former exhibited a significantly higher rate of severe exacerbation (0.22 vs. 0.12, p = 0.03). CONCLUSIONS: Prescriptions of ICS to treat COPD decreased with increased use of long-acting dual bronchodilators. ICS withdrawal might impact severe exacerbation; the potential risks and benefits of withdrawing ICS should therefore be considered based on patients' characteristics.


Asunto(s)
Corticoesteroides/administración & dosificación , Broncodilatadores/administración & dosificación , Progresión de la Enfermedad , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Administración por Inhalación , Anciano , Estudios de Cohortes , Análisis de Datos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , República de Corea/epidemiología , Resultado del Tratamiento
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