• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1430-1435
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• 2020

Bacterial cellulose (BC) has outstanding physical and chemical properties, including high crystallinity, moisture retention, and tensile strength. Currently, the major producer of BC is Komagataeibacter xylinus. However, due to limited tools of expression, this host is difficult to engineer metabolically to improve BC productivity. In this study, a regulated expression system for K. xylinus with synthetic ribosome binding site (RBS) was developed and used to engineer a BC biosynthesis pathway. A synthetic RBS library was constructed using green fluorescent protein (GFP) as a reporter, and three synthetic RBSs (R4, R15, and R6) with different strengths were successfully isolated by fluorescence-activated cell sorting (FACS). Using synthetic RBS, we optimized the expression of three homologous genes responsible for BC production, pgm, galU, and ndp, and thereby greatly increased it under both static and shaking culture conditions. The final titer of BC under static and shaking conditions was 5.28 and 3.67 g/l, respectively. Our findings demonstrate that reinforced metabolic flux towards BC through quantitative gene expression represents a practical strategy for the improvement of BC productivity.

• Journal of the Korean Society for information Management
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• v.28 no.1
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• pp.237-262
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• 2011

The purpose of this study is to understand the acceptance of the electronic journals among undergraduate students. Using a survey questionnaire, this study collected the data collected from 813 students taking 11 courses offered in five different universities. The levels of electronic jounal and its service awareness appeared to be low as 63.7% and 59.9% respectively. Only 43.8% of the respondents report their experience of using Korean e-journals. There is a statistically significant difference in use among college groups and students' major of study. E-journals are mostly used off-campus and within the library, using simple search techniques. In spite of difficulties in search and gathering information, the satisfaction level marked above average. Reasons of nonuse are lack of opportunity and knowledge. However, 93.8% of nonusers report a willingness to use the e-journals in the future. LIS students show higher e-journal awareness and use experience compared to non-LIS students. Yet, the levels of using simple search techniques and satisfaction show little difference from those of the non-LIS students. The findings of the study suggest implications to promote the acceptance of e-journals among college students.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.2
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• pp.121-126
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• 2001

A cDNA encoding a cathepsin D homologue was cloned from a cDNA library of the mulberry longicorn beetle, Apriona germari. Sequence analysis of the cDNA encoding the cathepsin D homologue of A. germari revealed that the 1,158 bp cDNA has an open reading frame of 386 amino acid residues. The deduced protein sequence of the A. germari cathepsin D homologue shows high homology with cathepsin D in insects, Aedes aegypti (68.2% amino acid similarity) and Drosophila melanogaster (67.2% amino acid similarity). Two aspartic residues and six cystein residues in the A. germari cathepsin D homologue are present at identical locations in all of the other catepsins D. Unlike cathepsins D in two insect species, A. gemari cathepsin D homologue appears to have two putative glycosylation sites, rather than one. Phylogenetic analysis revealed the A. germari cathepsin D homologue is more closely related to insect cathepsins D than to the other animal cathepsins D. Northern blot analysis suggests that A. germari cathepsin D homologue gene is expressed in most if not all, body tissues.

• Korean Journal of Plant Tissue Culture
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• v.28 no.4
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• pp.201-204
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• 2001

Acyl-CoA binding proteins (ACBP) are small highly-conserved cytosolic proteins that bind long-chain acyl-CoAs. A cDNA encoding ACBP was identified from cDNA library constructed from hairy root poly $A^{＋}$ RNA in expressed sequence tags (EST) analysis. The cDNA clone was 453 bp long and carried an open reading frame of 264 bp (10 kDa). The ginseng ACBP amino acid sequence was compared with other reported plant ACBPs using the CLUSTALW. Ginseng ACBP is 89%, 81%, 80%, and 73% identical with ACBP from castor bean, lilly, Digitalis and Arabidopsis, respectively. However, ginseng ACBP is 5 amino acids smaller than Arabidopsis and rape seed ACBPs. Also there is no any known signal peptide sequence in ginseng ACBP.

• Molecules and Cells
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• v.23 no.3
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• pp.316-322
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• 2007

Zinc finger transcription factor genes are a significant fraction of the genes in the vertebrate genome. Here we report the isolation and characterization of a human zinc finger-containing gene, ZNF435, from a fetal brain cDNA library. ZNF435 cDNA is 1290 base pairs in length and contains an open reading frame encoding 349 amino acids with four C2H2-type zinc fingers at its carboxyl terminus and a SCAN motif at its amino terminus. RT-PCR results showed that ZNF435 was expressed in all tested tissues. A ZNF435-GFP fusion protein was located in the nucleus and the four zinc fingers acted as nuclear localization signals (NLSs). ZNF435 was found to be capable of homo-association, and this effect was independent of its zinc fingers. Furthermore, ZNF435 proved to be a transcription repressor as its overexpression in AD293 cells inhibited the transcriptional activities of AP-1.

• Journal of fish pathology
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• v.23 no.3
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• pp.323-334
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• 2010

Bactericidal/permeability-increasing protein (BPI) and lipopolysaccharide-binding protein (LBP) are important components of the mammalian innate defence system against Gram-negative infections. The BPI/LBP cDNA was identified from the black rockfish ConA/PMA or LPS stimulated leukocyte cDNA library. The full-length BR-BPI/LBP cDNA was 2118 bp long and contained an open reading frame (ORF) of 1422 bp that encoded 473 amino-acid residues. The 5' UTR had a length of 57 bp, and the 3' UTR 639 bp. The molecular weight and theoretical isoelectric point (pI) values were calculated 51.4 kDa and 9.72, respectively. Compared with other known BPI or BPI/LBP peptide sequences, the most conserved regions of the black rockfish BPI/LBP peptide were found to be the BPI1 N-terminal, BPI2 C-terminal domains and a LPS binding domain. Phylogenetic analysis based on the deduced amino acid sequence revealed a homologous relationship between the BPI/LBP sequence of black rockfish and that of other teleosts. The black rockfish BPI/LBP gene was predominantly expressed in the PBLs, head kidney, trunk kidney and spleen. The expression of the black rockfish BPI/LBP molecule was induced in the peripheral blood leukocytes (PBLs) from 1 to 24 h following LPS stimulation, with a peak at 12 h post-stimulation.

• Journal of Periodontal and Implant Science
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• v.51 no.6
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• pp.386-397
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• 2021

Purpose: MicroRNAs (miRNAs) are epigenetic post-transcriptional regulators that modulate gene expression and have been identified as biomarkers for several diseases, including cancer. This study aimed to systematically review the relationship between miRNAs and periodontal disease in humans, and to evaluate the potential of miRNAs as diagnostic and prognostic biomarkers of disease. Methods: The review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines (reference number CRD42020180683). The MEDLINE, Scopus, Cochrane Library, Embase, Web of Science, and SciELO databases were searched for clinical studies conducted in humans investigating periodontal diseases and miRNAs. Expression levels of miRNAs across the different groups were analysed using the collected data. Results: A total of 1,299 references were identified in the initial literature search, and 23 articles were finally included in the review. The study designs were heterogeneous, which prevented a meta-analysis of the data. Most of the studies compared miRNA expression levels between patients with periodontitis and healthy controls. The most widely researched miRNA in periodontal diseases was miR-146a. Most studies reported higher expression levels of miR-146a in patients with periodontitis than in healthy controls. In addition, many studies also focused on identifying target genes of the differentially expressed miRNAs that were significantly related to periodontal inflammation. Conclusions: The results of the studies that we analysed are promising, but diagnostic tests are needed to confirm the use of miRNAs as biomarkers to monitor and aid in the early diagnosis of periodontitis in clinical practice.

• Mycobiology
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• v.47 no.2
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• pp.242-249
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• 2019

Betaine derivatives are considered major ingredients of shampoos and are commonly used as antistatic and viscosity-increasing agents. Several studies have also suggested that betaine derivatives can be used as antimicrobial agents. However, the antifungal activity and mechanism of action of betaine derivatives have not yet been fully understood. In this study, we investigated the antifungal activity of six betaine derivatives against Malassezia restricta, which is the most frequently isolated fungus from the human skin and is implicated in the development of dandruff. We found that, among the six betaine derivatives, lauryl betaine showed the most potent antifungal activity. The mechanism of action of lauryl betaine was studied mainly using another phylogenetically close model fungal organism, Cryptococcus neoformans, because of a lack of available genetic manipulation and functional genomics tools for M. restricta. Our genome-wide reverse genetic screening method using the C. neoformans gene deletion mutant library showed that the mutants with mutations in genes for cell membrane synthesis and integrity, particularly ergosterol synthesis, are highly sensitive to lauryl betaine. Furthermore, transcriptome changes in both C. neoformans and M. restricta cells grown in the presence of lauryl betaine were analyzed and the results indicated that the compound mainly affected cell membrane synthesis, particularly ergosterol synthesis. Overall, our data demonstrated that lauryl betaine influences ergosterol synthesis in C. neoformans and that the compound exerts a similar mechanism of action on M. restricta.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.8-8
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• 2019

The stringent response (SR) is characterized as a bacterial defense mechanism in response to various growth-inhibiting stresses. It is activated by accumulation of a small nucleotide regulator, (p)ppGpp, and induces global changes in bacterial transcription and translation. Recent work from our group has shown that (p)ppGpp plays a critical role in virulence and survival in Vibrio cholerae. The genes, relA and relV, are involved in the production of (p)ppGpp, while the spoT gene encodes an enzyme that hydrolyzes it in V. cholerae. A mutant strain defective in (p)ppGpp production (i.e. ${\Delta}relA{\Delta}relV{\Delta}spoT$ mutant) lost the ability to produce cholera toxin (CT) and lost their viability due to uncontrolled production of organic acids, when grown with extra glucose. In contrast, the ${\Delta}relA{\Delta}spoT$ mutant, a (p)ppGpp overproducer strain, produced enhanced level of CT and exhibited better growth in glucose supplemented media via glucose metabolic switch from organic fermentation to acetoin, a neutral fermentation end product, fermentation. These findings indicates that (p)ppGpp, in addition to its well-known role as a SR mediator, positively regulates CT production and maintenance of growth fitness in V. cholerae. This implicates SR as a promising drug target, inhibition of which may possibly downregulate V. cholerae virulence and survival fitness. Therefore, we screened a chemical library and identified a compound that induces medium acidification (termed iMAC) and thereby loss of wild type V. cholerae viability under glucose-rich conditions. Further, we present a potential mechanism by which the compound inhibits (p)ppGpp accumulation. Together, these results indicate that iMAC treatment causes V. cholerae cells to produce significantly less (p)ppGpp, an important regulator of the bacterial virulence and survival response, and further suggesting that it has a therapeutic potential to be developed as a novel antibacterial agent against cholera.

• Animal Bioscience
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• v.35 no.7
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• pp.975-988
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• 2022

Objective: In this study, we aimed to identify long non-coding RNAs (lncRNAs) that play important roles in starvation stress, analyze their functions, and discover potential molecular targets to alleviate starvation stress to provide a theoretical reference for subsequent in-depth research. Methods: We generated a piglet starvation stress animal model. Nine Yorkshire weaned piglets were randomly divided into a long-term starvation stress group (starved for 72 h), short-term starvation stress group (starved for 48 h), and the control group. LncRNA libraries were constructed using high-throughput sequencing of piglet ileums. Results: We obtained 11,792 lncRNAs, among which, 2,500 lncRNAs were novel. In total, 509 differentially expressed (DE)lncRNAs were identified in this study. Target genes of DElncRNAs were predicted via cis and trans interactions, and functional and pathway analyses were performed. Gene ontology functions and Kyoto encyclopedia of genes and genomes analysis revealed that lncRNA-targeted genes mainly participated in metabolic pathways, cellular processes, immune system processes, digestive systems, and transport activities. To reveal the mechanism underlying starvation stress, the interaction network between lncRNAs and their targets was constructed based on 26 DElncRNAs and 72 DEmRNAs. We performed an interaction network analysis of 121 DElncRNA-DEmRNA pairs with a Pearson correlation coefficient greater than 0.99. Conclusion: We found that MSTRG.19894.13, MSTRG.16726.3, and MSTRG.12176.1 might play important roles in starvation stress. This study not only generated a library of enriched lncRNAs in piglets, but its outcomes also provide a strong foundation to screen key lncRNAs involved in starvation stress and a reference for subsequent in-depth research.