• Journal of Microbiology and Biotechnology
• /
• v.26 no.3
• /
• pp.603-609
• /
• 2016

Brucellosis affects a wide range of host species, including humans and many livestock animals. Chronic infections of the disease make antibiotic treatment costly, and the current vaccine used in livestock has not been approved for human use. This study investigated the possible use of the Brucella abortus outer membrane protein A (OmpA) as a candidate subunit vaccine in an infected mouse model. The ompA gene was cloned and overexpressed, and the recombinant OmpA (rOmpA) protein fused to maltose binding protein (MBP) was purified in Escherichia coli. Immunogenicity was verified through western blotting, and mice were immunized and challenged to evaluate its protective effect. Mice treated with rOmpA exhibited induced humoral and host cell-mediated responses, with a significant increase in immunoglobulin G (IgG1 and IgG2a) and cytokine levels, especially TNF-α and IL-12, compared with the control groups treated with either MBP or PBS. In conclusion, rOmpA should be highly considered as a future subunit vaccine for brucellosis, and further studies regarding rOmpA and its protective ability are suggested.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.9
• /
• pp.873-880
• /
• 2009

A novel xylanase gene, Kxyn, was cloned from Kocuria sp. Mn22, a bacteria isolated from the deep sea of the east Pacific. Kxyn consists of 1,170 bp and encodes a protein of 390 amino acids that shows the highest identity (63%) with a xylanase from Thermohifida fusca YX. The mature protein with a molecular mass of approximately 40 kDa was expressed in Escherichia coli BL21 (DE3). The recombinant Kxyn displayed its maximum activity at $55^{\circ}C$ and at pH 8.5. The $K_m,\;V_{max}$, and $k_{cat}$ values of Kxyn for birchwood xylan were 5.4 mg/ml, $272{\mu}mol/min{\cdot}mg$, and 185.1/s, respectively. Kxyn hydrolyzed birchwood xylan to produce xylobiose and xylotriose as the predominant products. The activity of Kxyn was not affected by $Ca^{2+},\;Mg^{2+},\;Na^+,\;K^+$, ${\beta}$-mercaptoethanol, DTT, or SDS, but was strongly inhibited by $Hg^{2+},\;Cu^{2+},Zn^{2+}$, and $Pb^{2+}$. It was stable over a wide pH range, retaining more than 80% activity after overnight incubation at pH 7.5-12. Kxyn is a cellulase-free xylanase. Therefore, these properties make it a candidate for various industrial applications.

• Journal of Microbiology and Biotechnology
• /
• v.28 no.11
• /
• pp.1846-1849
• /
• 2018

Recent human gut microbiome studies have supported that the genus Bifidobacterium is one of the most beneficial bacteria for human intestinal health. To develop a new probiotic strain for functional food applications, fourteen fecal samples were collected from healthy Koreans and the strain BCBR-583 was newly selected and isolated from a 25-year-old Korean woman's fecal sample using the selective medium for Bifidobacterium. Subsequent fructose-6-phosphate phosphoketolase (F6PPK) test and 16S rRNA gene sequencing analysis of the strain BCBR-583 confirmed that it belongs to B. longum subsp. longum. The stress resistance tests showed that it has oxygen and heat tolerance activities (5- and 3.9-fold increase for 24 h at 60 and 120 rpm, respectively; $78.61{\pm}6.67%$ survival rate at $45^{\circ}C$ for 24 h). In addition, gut environment adaptation tests revealed that this strain may be well-adapted in the gut habitat, with gastric acid/bile salt resistance ($85.79{\pm}1.53%$, survival rate under 6 h treatments of gastric acid and bile salt) and mucin adhesion ($73.72{\pm}7.36%$). Furthermore, additional tests including cholesterol lowering assay showed that it can reduce $86.31{\pm}1.85%$ of cholesterol. Based on these results, B. longum BCBR-583 has various stress resistance for survival during food processing and environmental adaptation activities for dominant survival in the gut, suggesting that it could be a good candidate for fermented food applications as a new probiotic strain.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.9
• /
• pp.1351-1358
• /
• 2010

The demand for ${\beta}$-glucosidases insensitive to product inhibition is increasing in modern biotechnology, for these enzymes would improve the process of saccharification of lignocellulosic materials. In this study, a ${\beta}$-glucosidase gene that encodes a 442-amino-acid protein was isolated from a marine microbial metagenomic library by functional screening and named as bgl1A. The protein was identified to be a member of the glycoside hydrolases 1 family, and was recombinantly expressed, purified, and biochemically characterized. The recombinant ${\beta}$-glucosidase, Bgl1A, exhibited a high level of stability in the presence of various cations and high concentrations of NaCl. Interestingly, it was activated by glucose at concentrations lower than 400 mM. With glucose further increasing, the enzyme activity of Bgl1A was gradually inhibited, but remained 50% of the original value in even as high as 1,000 mM glucose. These findings indicate that Bgl1A might be a potent candidate for industrial applications.

• Molecules and Cells
• /
• v.28 no.6
• /
• pp.553-558
• /
• 2009

In the periphery, a galectin-1 receptor, CD7, plays crucial roles in galectin-1-mediated apoptosis of activated T-cells as well as progression of T-lymphoma. Previously, we demonstrated that $NF-{\kappa}B$ downregulated CD7 gene expression through the p38 MAPK pathway in developing immature thymocytes. However, its regulatory pathway is not well understood in functional mature T-cells. Here, we show that CD7 expression was downregulated by Twist2 in Jurkat cells, a human acute T-cell lymphoma cell line, and in EL4 cells, a mature murine T-cell lymphoma cell line. Furthermore, ectopic expression of Twist2 in Jurkat cells reduced galectin-1-induced apoptosis. While full-length Twist2 decreased CD7 promoter activity, a C-terminal deletion form of Twist2 reversed its inhibition, suggesting an important role of the C-terminus in CD7 regulation. In addition, CD7 expression was enhanced by histone deacetylase inhibitors such as trichostatin A and sodium butyrate, which indicates that Twist2 might be one of candidate factors involved in histone deacetylation. Based on these results, we conclude that upregulation of Twist2 increases the resistance to galectin-1-mediated-apoptosis, which may have significant implications for the progression of some T-cells into tumors such as Sezary cells.

• Food Science of Animal Resources
• /
• v.40 no.3
• /
• pp.362-376
• /
• 2020

Rabbit meat bekasam is a traditional fermentation product from Indonesia. This study aimed to determine the chemical and microbiological characteristics of rabbit meat bekasam during the fermentation process in order to isolate, characterize (in vitro and in vivo), and identify lactic acid bacteria (LAB) as the probiotic candidate. The chemical contents of bekasam on 7-day fermentation were investigated in explorative and experimental methods in a completely randomized design. A proximate analysis reported a decrease in the moisture content, fat and carbohydrate content, and an increase in protein content. Also, lactic acid content was increased from 0.48% to 1.12%, and pH was decreased from 5.3 to 4.3. Other properties indicated different values, such as bacteria (2.75×10⁶ to 4.45×10⁷ CFU/g), total LAB (3.82×10⁶ to 4.67×10⁸ CFU/g), total yeast (9.89×10⁶ to 3.82×10⁸ CFU/g) and total mould (4.34×10¹ to 4.86×10³ CFU/g). The experiment produced nine LAB isolates, including two probiotics subjected to further 16S rRNA gene analysis, which indicated that Lactobacillus buchneri was the potential probiotic isolate. After being tested on BALB/c mice, L. buchneri could improve the immune system by inhibiting the growth of Coliform and Salmonella.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.17
• /
• pp.7443-7447
• /
• 2014

Aim: Little is known about the genetic associations with Basal cell carcinoma (BCC) risk in non-Caucasian populations, in which BCC is rare, as in Korea. We here conducted a pilot genome-wide association study (GWAS) in 12 patients and 48 standard controls. Method: A total of 263,511 SNPs were analyzed with the Illumina HumanOmni1 Quad v1.0 DNA Analysis BeadChip for cases and Korean HapMap 570K for controls. Results: SNP-based analyses, based on the allele genetic model with adjustment for sex and age showed suggestive associations with BCC risk for 6 SNPs with a P-value (P < 0.0005). However, these associations were not statistically significant after Bonferroni correction: rs1040503, rs2216491, rs13407683, rs4751072, rs9891263, and rs1368474. In addition, results from gene-based analyses showed suggestive associations with BCC risk for 33 candidate genes with a P-value (P <0.0005). Consistent with previous GWAS and replication studies in Caucasian populations, PADI6, RHOU and SLC45A2 were identified as having null associations with BCC (P > 0.05), likely due to the smaller sample size. Conclusions: Although this was a small-scale negative study, to our knowledge, we have conducted the first GWAS for BCC risk in an Asian population. Further large studies in non-Caucasian populations are required to achieve statistical significance and confirm these findings.

• The Plant Pathology Journal
• /
• v.28 no.1
• /
• pp.40-48
• /
• 2012

$Potato$ $virus$ $X$ (PVX) replication is precisely regulated by regulatory viral sequences and by viral and/or host proteins. In a previous study, we identified a 54-kDa cellular tobacco protein that bound to a region within the first 46 nucleotides (nt) of the 5' non-translated region (NTR) of the viral genome. Optimal binding was dependent upon the presence of an ACCA sequence at nt 10-13. To identify host factors that bind to 5' NTR elements including AC-rich sequences as well as stemloop 1 (SL1), we used northwestern blotting and matrixassisted laser desorption/ionization time-of-flight mass spectrometry for peptide mass fingerprinting. We screened several host factors that might affect PVX replication and selected a candidate protein, $Nicotiana$ $tabacum$ WRKY transcription factor 1 (NtWRKY1). We used a $Tobacco$ $rattle$ $virus$ (TRV)-based virus-induced gene silencing (VIGS) system to investigate the role of NtWRKY1 in PVX replication. Silencing of $WRKY1$ in $Nicotiana$ $benthamiana$ caused lethal apical necrosis and allowed an increase in PVX RNA accumulation. This result could reflect the balancing of PVX accumulation in a systemic $N.$ $benthamiana$ host to maintain PVX survival and still produce a suitable appearance of mosaic and mottle symptoms. Our results suggest that PVX may recruit the WRKY transcription factor, which binds to the 5' NTR of viral genomic RNA and acts as a key regulator of viral infection.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.1
• /
• pp.387-393
• /
• 2016

Background: CYP1A1 is a candidate gene for low-penetrance breast cancer susceptibility, as it plays an important role in the metabolism of carcinogens and estrogens. Purpose: The objective of this study was to assess the association between M2 (A2455G, Ile462Val) and M4 (C2453A, Thr461Asn) polymorphisms in CYP1A1 and breast cancer risk among Jordanian women and in subgroups stratified by menopausal status and smoking history. Materials and Methods: Blood samples were collected from 112 breast cancer female patients and 115 age-matched controls who underwent breast cancer screening with imaging and showed negative results (BI-RADS I or BI-RADS II). Genotyping was performed using the PCR-RFLP technique. Results: No statistically significant overall association was found between breast cancer risk and CYP1A1 M2 genotypes (p= 0.55; OR = 0.77; 95% CI= 0.32 - 1.83) nor with the M4 polymorphism (p= 0.95; OR= 0.95; 95% CI= 0.51 - 1.88). Analysis of subgroups defined by menopausal status or smoking history also revealed no association with these polymorphisms. Furthermore, the four identified haplotypes (AC; AA; GC and GA) were equally distributed among cases and controls, and haplotype analysis showed a strong linkage disequilibrium of both studied loci in either cases or controls (D'=1). Conclusions: Based on the study results, CYP1A1 M2 and M4 polymorphisms do not seem to play a major role in breast cancer risk among Jordanian females.

• BMB Reports
• /
• v.41 no.6
• /
• pp.466-471
• /
• 2008

Three isoforms of pig PDE4B were cloned and classified as two forms: PDE4B1 and PDE4B3, which contain UCR1 and UCR2; and PDE4B2, which contains only UCR2. The amino acid sequences of each isoform showed good conservation in human and rat. PDE4B2 is expressed in a wide range of tissues, but PDE4B1 and PDE4B3 are not. Using an informative SNP for the Iberian x Landrace intercross detected from intron 12, a linkage map was constructed. The location of PDE4B was estimated at 123.6 cM outside of the QTL-CI (124-128 cM) for IMF. However, the QTL-CI for IMF was reconfirmed with high significance, and its position was narrowed down to an interval of 4 cM (the region defined by markers PDE4B and SW1881). Using radiation hybrid mapping, LEPR, LEPROT, DNAJC6, AK3L1 and AK3L2 were selected as positional and/or functional candidates related to the QTL.