The Bacterial Surface Expression of SARS Viral Epitope using Salmonella typhi Cytolysin A

Piao, Hong-Hua,Seong, Ji-Hyoun,Song, Man-Ki,Kim, Youn-Uck,Shin, Dong-Jun,Choy, Hyon-E,Hong, Yeong-Jin The Korean Society for Microbiology 2009 Journal of Bacteriology and Virology Vol.39 No.2

The cytolysin A (ClyA) is a 34 kDa pore-forming cytotoxic protein and expressed by some enteric bacteria including Salmonella typhi. This toxin is transported on the bacterial surface and secreted without posttranslational modification. Using the surface display of ClyA, the expression vectors for 193-aa immunogenic antigen of spike protein (termed S1E) from severe acute respiratory syndrome coronavirus (SARS-CoV) were constructed. The vectors carried a gene encoding S. typhi ClyA conjugated to S1E at the C terminus (termed ClyA-S1E) and asd gene in pGEM-T and pBR322, named pGApLCS1E and pBApLCS1E, respectively. An asd-mutated E. coli transformed with these vectors could grow without diaminopimelic acid (DAP), indicating that they were stably maintained in such mutants. ClyA-S1E recombinant proteins from these vectors were expressed on the surface of the attenuated S. typhimurium deficient of global virulence gene regulator, ppGpp. However, they did not show the hemolytic activity on the blood agar plate and cytotoxicity against HeLa cells. To examine whether bacteria expressing ClyA-S1E induced the immune response against S1E, S. typhimurium deficient of ppGpp and Asd was transformed with these vectors and orally immunized in mice. In the western blotting against GST-conjugated S1E using the immunized mouse sera, it was shown that the significant band was detected in the mouse serum by the bacteria transformed with pGApLCS1E but not with pBApLCS1E. It indicates that the immune response producing antibody was dependent on the expression level of ClyA-S1E. Therefore, ClyA delivery system can be used for SARS vaccine development.

Amino acid residues in the Ler protein critical for derepression of the LEE5 promoter in enteropathogenic E. coli

Su-Mi Choi,Jae-Ho Jeong,Hyon E. Choy,Minsang Shin 한국미생물학회 2016 The journal of microbiology Vol.54 No.8

Enteropathogenic E. coli causes attaching and effacing (A/E) intestinal lesions. The genes involved in the formation of A/E lesions are encoded within a chromosomal island comprising of five major operons, LEE1-5. The global regulator H-NS represses the expression of these operons. Ler, a H-NS homologue, counteracts the H-NS–mediated repression. Using a novel genetic approach, we identified the amino acid residues in Ler that are involved in the interaction with H-NS: I20 and L23 in the C-terminal portion of α-helix 3, and I42 in the following unstructured linker region.

장기적인 hGH 처치와 사다리 오르기가 노화된 암컷 흰쥐 FHL의 형태학적, 효소학적 특성에 미치는 영향

권율이 ( Yul E Kwon ),정대모 ( Dae Mo Chung ),박현 ( Hyon Park ) 한국운동영양학회 2004 Physical Activity and Nutrition (Phys Act Nutr) Vol.8 No.1

The effects of hGH, resistance exercise, and the combination of them on morphological and enzymological properties especially of FHL in old female SD rats were investigated in this study. Thirsty one rats were divided into 4 groups including control; C (n=7), hGH administration; (n=8), resistance exercise; (n=8) and hGH plus resistance exercise; X (n=8). An hGH solution (somatropin, Saizen) was injected with 2.5 mg/kg/day dose to group G and X, and the same volume of saline was injected to group C and E. Resistance training was loaded by climbing 100 cm and 85 degrees ladder with certain weight at rat`s tail. And the load was gradually increased daily and periods based to the max. During eight weeks of treatment, through Muscle fiber type distribution, capillary density, citrate synthase enzyme activity and β-HAD, we can analyze morphological and enzymological properties especially in FHL.In the ability of the exercise their ability to climb ladder with some loads suspended their tails was improved continuously. In enzyme activities, but GH has basically lipid metabolism effect, E group has higher values than G and X group in β-HAD. Through these, resistance training has more effects than GH administration. Meanwhile, C group has lower value than E group in citrate synthase because our training was a high intensity resistance training, it would affect anaerobic metabolism.

Initial Characterization of yliH in Salmonella typhimurium

Park, Kyung-Hwa,Song, Mi-Ryung,Choy, Hyon-E. The Microbiological Society of Korea 2007 The journal of microbiology Vol.45 No.6

Using microarray analysis, we determined those Salmonella genes induced at the entry of stationary phase, and subsequently discovered that uncharacterized yliH was induced most dramatically. We set out to establish the molecular mechanism underlying the stationary phase induction of yliH under the standard culture condition, LB with vigorous aeration, by analyzing its promoter activity in various mutant backgrounds, lacking stationary phase ${\sigma}$, $RpoS^-$, or stringent signal molecules ppGpp, ${\Delta}relA$ ${\Delta}spoT$. It was found that the stationary phase induction of yliHp was partially dependent on rpoS but entirely dependent on ppGpp. DNA sequence analysis revealed that the Salmonella yliH gene is composed of 381 base-pair nucleotides, with overall amino acid sequence revealing 76.38% amino acid identity and 88.98% similarity with Escherichia coli yliH, although no motif from data base was noted for its possible role. Recently however, it has been reported that yliH in E. coli was implicated in biofilm formation and motility by repressing these activities (Domka et al., 2006). We have constructed a mutant Salmonella deleting yliH gene by allele replacement and examined its phenotype, and found that the yliH in Salmonella more or less affects motility and adherence by enhancing these activities. The effect on biofilm formation in Salmonella was uncertain. Moreover, addition of cloned yliH of E. coli into Salmonella did not reduce motility or adherence. Taken together, it appears that the pathways implicating yliH for biofilm formation and motility in E. coli and in Salmonella are somewhat different.

RE-09 : High mobility group box-1 and Toll like receptor 4 in Endometriosis: Mediating NF-kB pathway

( Bo Hyon1 ),( Yun Ji Jung ),( Seung Joo Chon ),( Yoo Jin Lee ),( E Jung Han ),( Sihyun Cho ),( Young Sik Choi ),( Byung Seok Lee ),( Seok Kyo Seo ) 대한산부인과학회 2014 대한산부인과학회 학술대회 Vol.100 No.-

목적: The aim of the study was to examine the sterile, chronic inflammatory status in endometriosis by detecting High mobility group box-1 (HMGB-1), and HMGB-1 signaling through toll like receptor (TLR) 4 in endometrial stromal cell, which activates NF-kB pathway that might play a pathogenic role in endometriosis. 방법: Total 69 patients who had undergone hysterectomy from March, 2012 to March, 2014 were included: 39 patients who had endometriosis as case group, 30 participants without endometriosis as the control. Expression of HMGB-1 in endometrium was examined by immunohistochemistry. From endometriosis patient, eutopic endometrium was obtained and used to culture in vitro. To confirm the association of HMGB-1 and TLR4 in NF-kB pathway, the cultured human endometrial stromal cells (HESCs) were treated with recombinant HMGB-1 (15 ng/mL) for 0, 12, 24, 48 hrs. TLR4 antagonist (LPS-RS) was added after rHMGB-1 treatment to HESCs to see the change of proliferation after inhibiting TLR4. CCK8 proliferation assay kit. Real-time PCR and western blotting were used to examine the proliferation, quantification of the mRNA and protein. Specific inhibitor of NF-κB signaling pathway (TPCA-1) was used to explore the role of NF-κB signaling pathway in HESCs proliferation. 결과: HMGB-1 expression was significantly higher in glandular epithelial and stromal cells of endometriosis group compared to the controls. rHMGB-1 significantly enhanced cell proliferation in HESCs and increased TLR4 expression by dose dependent fashion. Inhibiting TLR4 by LPS-RS, cell proliferation in HESCs and expression of TLR4 were significantly decreased comparing to the controls. After blocking NF-kB pathway with TPCA-1, cell proliferation in HESCs was significantly decreased by dose dependent fashion. 결론: This study showed that HMGB-1 may play an important role through TLR4 and NF-kB pathway, in inflammatory cascade of pathogenesis in endometriosis.

Salmonella 병원성의 분자생물학적 기전

최현일,송미령 全南大醫大 2004 전남의대학술지 Vol.40 No.1

자발형성 양자점의 선택성장 기술

김은규,이창효,김채옥,홍진표,현찬경,박용주 漢陽大學校 自然科學硏究所 2003 自然科學論文集 Vol.22 No.-

본 연구에서는 단전자 소자를 제조하는데 활용될 수 있도록 자발형성된 InGaAs/GaAs, InAs/GaAs 양자점의 선택성장기법에 대해 조사하였다. 먼저 분자선 에피탁시를 이용하여 GaAs 기판위에 InAs/GaAs 변형된 초격자 버퍼층을 성장시킨 후 InGaAs 양자점을 형성시켰으며, 형성된 양자점의 성장이 규칙적으로 나열 되는 메카니즘을 연구하였다. InAs/GaAs초격자는 InGaAs버퍼층에 비해 성장된 결정의 균일성이 좋음에도 In비율 조절이 용이하기 때문에 양자점을 제어하는데 좋은 버퍼층이라 하겠다. 또한 원자력간 현미경의 탐침을 이용한 직접 기록방식을 이용하여 기판 상에 패턴을 형성한 후 자발형성 양자점을 성장하여 위치의 배열화가 가능하도록 하였다. AFM 피에조 스캐너에 인가되는 전압 및 속도 조절을 통해 패턴의 폭과 깊이조절이 가능하였고 후 성장을 통하여 양자점이 패턴에 우선적으로 성장되는 것을 확인하였다. 이 같은 자발형성 양자점의 선택성장 기술은 신기능 나노소자제조를 위하여 응용될 수 있다. 이러한 정렬된 양자점은 단일전자소자등에 응용이 가능할 것이다. We have investigated selective growth method of InGaAs/GaAs, InAs/GaAs self assembled quantum dots for the application on single electron tunneling transistor. The first method uses molecular beam epitaxy to grow modified InAs/GaAs superlattice buffer layer on GaAs substrate. InAs/GaAs superlattice has a better crystalline uniformity than InGaAs buffer layer and has a better controllability of In Content which is suitable for the control of quantum dot growth. In another approach, we used the probe of the atomic force microscopy to directly pattern semiconductor surface allowing the position control in the subsequent quantum dot growth. The modulation voltage applied to the piezo scanner and the patterning speed was changed to obtain the controllability of the width and depth of the fabricated pattern. After quantum dot regrowth, we observed that the quantum dots were selectively grown on the pattern. These novel methods for self-assembled quantum dot selective growth can be applied to new functional nano-scaled devices. These well-aligned quantum dots could be applied for applications such as single electron tunneling devices.

Bioinformatics and Systems Biology : The effect of serine hydroxamate on protein expression in E. coli

( Won Tae Jung ),( Hyon E Choy ),( Che Hun Jung ) 한국생화학분자생물학회 (구 한국생화학회) 2008 생화학분자생물학회 춘계학술발표논문집 Vol.2008 No.-

DNA looping-dependent autorepression of <i>LEE1</i> P1 promoters by Ler in enteropathogenic <i>Escherichia coli</i> (EPEC)

Bhat, Abhayprasad,Shin, Minsang,Jeong, Jae-Ho,Kim, Hyun-Ju,Lim, Hyung-Ju,Rhee, Joon Haeng,Paik, Soon-Young,Takeyasu, Kunio,Tobe, Toru,Yen, Hilo,Lee, Gwangrog,Choy, Hyon E. National Academy of Sciences 2014 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.111 No.25

<P>Ler, a homolog of H-NS in enteropathogenic <I>Escherichia coli</I> (EPEC), plays a critical role in the expression of virulence genes encoded by the pathogenic island, locus of <I>e</I>nterocyte <I>e</I>ffacement (LEE). Although Ler acts as an antisilencer of multiple <I>LEE</I> operons by alleviating H-NS–mediated silencing, it represses its own expression from two <I>LEE1</I> P1 promoters, P1A and P1B, that are separated by 10 bp. Various in vitro biochemical methods were used in this study to elucidate the mechanism underlying transcription repression by Ler. Ler acts through two AATT motifs, centered at position −111.5 on the coding strand and at +65.5 on the noncoding strand, by simultaneously repressing P1A and P1B through DNA-looping. DNA-looping was visualized using atomic force microscopy. It is intriguing that an antisilencing protein represses transcription, not by steric exclusion of RNA polymerase, but by DNA-looping. We propose that the DNA-looping prevents further processing of open promoter complex (<I>RP</I><SUB><I>O</I></SUB>) at these promoters during transcription initiation.</P>

RE-17 : The relationship between serum ferritin levels and the obesity in Korean women

( E Jung Han ),( Bo Hyon Yun ),( Seung Joo Chon ),( Yoo Jin Lee ),( Young Sik Choi ),( Byung Seok Lee ),( Seok Kyo Seo ) 대한산부인과학회 2014 대한산부인과학회 학술대회 Vol.100 No.-

목적: Elevated serum ferritin levels are associated with insulin resistance, type 2 diabetes, cardiovascular disease, and metabolic syndrome. To date, however, no cohort studies have examined whether serum ferritin levels are an independent risk factor for the obesity. Therefore, we conducted a retrospective study to evaluate the relationship between serum ferritin levels and obesity development in Korean women. 방법: Total 23,055 healthy Korean women who participated in Korean National Health and Nutrition Examination Survey in 2007-2011. Obesity was defined as a body mass index ≥25 kg/m2. Multiple regression analyses were performed taking into account ferritin as the dependent variable. 결과: Among 23,055 healthy Korean women, 5183 patients was diagnosed obesity. After adjusting for multiple covariates, obesity was more prevalent in the highest quartile compared with the lowest quartile of serum ferritin (odds ratio=1.52; p<0.001 vs odds ratio=1.16; p=0.031). Abdominal obesity based on waist circumference (≥ 85 cm) was more common in the highest compared with the lowest quartile of serum ferritin (odd ratio=1.20; p=0.009 vs odds ratio=1.60; p<0.001). Insulin, glucose and HOMA-IR showed consistent longitudinal associations (p for trend <0.001). 결론: The present study demonstrates that elevated serum ferritin levels may have been a predictive factor for obesity in a representative sample of South Korean women.