• Korean Journal of Microbiology
• /
• v.51 no.2
• /
• pp.169-176
• /
• 2015

The malolactic fermentation (MLF), which is widely used in winemaking, is the conversion of malic acid to lactic acid conducted by the malolactic enzyme (Mle) of lactic acid bacteria. In order to select the strains with MLF among 54 lactic acid bacteria isolated from the traditionally fermented foods, we designed a primer set that specifically targets the conserved regions of the mle gene and then selected four strains that harbor the mle gene of Lactobacillus plantarum. All strains were identified as L. plantarum by analyzing the 16S rRNA sequences, biochemical properties, and the PCR products of the recA gene. From comparison of the mle gene sequences consisting of 1,644 bp, the nucleotide and amino acid sequence of strain JBE60 correspond to 96.7% and 99.5% with those of other three strains, respectively. The strain JBE60 showed the highest resistant against 10% (v/v) ethanol among the strains. The strains lowered the concentration of malic acid to average 43%. Considering the ethanol resistance and conversion of malic acid, the strain JBE60 is considered as a potential starter for the malolactic fermentation.

• Journal of Life Science
• /
• v.9 no.2
• /
• pp.176-181
• /
• 1999

In order to understand molecular phylogenetics of silkworm (Bombyx mori), we analyzed the sequences of BmoMAR isolated from Bomhyx mori that is partial coding gene of transposase of mariner-like element(MLE). By pairwise comparing nucleotide sequences of BmoMAR with ten previously reported insect MLEs accessed in GeneBank, the average genetic distance was estimated to be 0.4840. The phylogenetics tree constructed from nine insect species except for human MLE(Hsmarl) by UPGMA method indicated that MLEs are divided into three clusters, and Drosophila mariutiana was independently subgrouped. Bombyx mori(BmoMAR) was subgrouped with microcaddishfly (Orthotrichia cristata), webworm(Atteva punctella), almond moth(Ephestia cautella), Hyalopora cecropia which we lepidoptera. Phylogenetics tree according to UPGMA principle, on the basis of informative nucleotide sequences of nine insect MLEs, indicated that Bombyx mori was more closely related to microcaddishfly(Orthotrichia cristata) and webworm (Atteva punctella) of lepidoptera. We suggest that insect MLEs are a useful key for studying molecular phylogenetics among intra species of insects.

• Journal of Life Science
• /
• v.8 no.3
• /
• pp.285-293
• /
• 1998

We have cloned an internal fragment of the putative transoisase gene of MLE in the silkworm, Bombyx mori, using PCR method with degenerative oligonucleotide primers designed to represent regions of amino acids encoding transposase. The resulting PCR clone, designed as BmoMAR, cords a partial ORF(152 a.a.) of MLE in which interrupted by five stop codons, and the sequence of its deduced amino acids showed 37% homology with Mos1, an active mariner, from Drosophila mauritiana. Furthermore, the BmoMAR exhibits nucleotide and amino acid homology with 59% and 37% from Apis mellifera and D. mauritiana 7.9 clone, respectively. This result strongly that a MLE is present in the genome of B. mori.

• Journal of Life Science
• /
• v.8 no.4
• /
• pp.457-464
• /
• 1998

As a first step for developing universal genetic transformation vector of dilkmoths., we identified the presence of mariner-like element(MLE) which is one of transposable element discovered from many insects to human species, from Bombyx mori, Bombyx mandarina, Antherae yammamai and Antherae pernyi. We used a degenerative primer pair designed from a transposase gene of Drosophila mauritiana and Hyalophora ceropia MLE. As results, major PCR product of 500bp expected as a part of transposase of MLE was detected from all the slkmoths used of this study using these primer. And hybridization assay using pBmoMAR as a probe DNA that was previously cloned from Bombyx mori by the same primer pair, confirmed the presence of MLE from all the silkmoths. This assay showed also that the endogenous MLE in genome of the silkworm is present as high copy number unlikely Drosophila mauritiana which has 10-20 copy number. This data will be a fundamental genetic information for developing mariner-derived vector to transform the silkmoths and other useful insects.

• Journal of Korean Society of Water and Wastewater
• /
• v.26 no.4
• /
• pp.591-598
• /
• 2012

Denitrification is an important biological mechanism in wastewater treatment process because this process is technically to remove nitrogen from water to air. There have been lots of study about denitrification engineering and molecular biological research about denitrifying bacteria, respectively. However, combination of these researches was unusual and rare. This study is about the correlation between quantity of denitrifying bacteria and denitrification potential, and consists of NUR batch test as analysis method of denitrification potential and quantitative molecular analysis for denitrifying bacteria. Three reactors (A/O, MLE and A/O of nitrogen deficiency) are operated to get activated sludge with various denitrification potential. All samples which were acquired from reactors were measured denitrification potential by NUR test and NUiR test. Also, Real-time PCR was conducted for quantification of denitrifying bacteria composition in activated sludge. The various denitrification potentials were measured in the reactors. The denitrifiaction potential was the highest in MLE process and the reactor of the nitrogen deficiency showed the lowest. Genomic DNA of activated sludge was obtained and consequently, real-time PCRuse the primer sets of nirK and nirS　were conducted to quantify genes involving denitrification reductase production. As the result of real-time PCR, nirK gene showed more significant influence on denitrification potential comapred with nirS gene.

• Korean Journal of Food Science and Technology
• /
• v.52 no.2
• /
• pp.191-199
• /
• 2020

The purpose of this study was to isolate novel lactic acid bacteria to ferment mulberry leaf extract (MLE) and to investigate its anti-diabetic effect. Lactobacillus plantarum SG-053 isolated from gatkimchi was selected to ferment MLE because it exhibited high α-glucosidase inhibitory activity (96.8%) and enhanced the content of 1-deoxynojirimycin (DNJ), an anti-diabetic substance, in fermented MLE up-to 2.2 times. MLE fermented with L. plantarum SG-053 (FMLE) showed growth promoting activity against L6 myotubes and increased the gene expressions of IRS-1, PI3K p85α, and GLUT-4 up-to 1.4, 2.2, and 1.4 times, respectively, and 2-deoxyglucose uptake up-to 40.7%. In rat skeletal muscle tissue, the expressions of PI3K p85α and GLUT-4 increased by 6.4 and 2.1 times, respectively. These results suggest that L. plantarum SG-053 could enhance the DNJ content of MLE by fermentation and that FMLE is effective in ameliorating insulin resistance via activation of the insulin signaling pathway.

• Tuberculosis and Respiratory Diseases
• /
• v.82 no.2
• /
• pp.133-142
• /
• 2019

Background: Idiopathic pulmonary fibrosis involves irreversible alveolar destruction. Although alveolar epithelial type II cells are key functional participants within the lung parenchyma, how epithelial cells are affected upon bleomycin (BLM) exposure remains unknown. In this study, we determined whether BLM could induce cell cycle arrest via regulation of Schlafen (SLFN) family genes, a group of cell cycle regulators known to mediate growth-inhibitory responses and apoptosis in alveolar epithelial type II cells. Methods: Mouse AE II cell line MLE-12 were exposed to $1-10{\mu}g/mL$ BLM and $0.01-100{\mu}M$ baicalein (Bai), a G1/G2 cell cycle inhibitor, for 24 hours. Cell viability and levels of pro-inflammatory cytokines were analyzed by MTT and enzyme-linked immunosorbent assay, respectively. Apoptosis-related gene expression was evaluated by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). Cellular morphology was determined after DAPI and Hoechst 33258 staining. To verify cell cycle arrest, propidium iodide (PI) staining was performed for MLE-12 after exposure to BLM. Results: BLM decreased the proliferation of MLE-12 cells. However, it significantly increased expression levels of interleukin 6, tumor necrosis factor ${\alpha}$, and transforming growth factor ${\beta}1$. Based on Hoechst 33258 staining, BLM induced condensation of nuclear and fragmentation. Based on DAPI and PI staining, BLM significantly increased the size of nuclei and induced G2/M phase cell cycle arrest. Results of qRT-PCR analysis revealed that BLM increased mRNA levels of BAX but decreased those of Bcl2. In addition, BLM/Bai increased mRNA levels of p53, p21, SLFN1, 2, 4 of Schlafen family. Conclusion: BLM exposure affects pulmonary epithelial type II cells, resulting in decreased proliferation possibly through apoptotic and cell cycle arrest associated signaling.