• 생명과학회지
• /
• 제15권6호
• /
• pp.928-934
• /
• 2005

ATF2는 c-Fos와 c-Jun과 같은 전사인자이며 이들은 루신지퍼 단백질이다. 루신지퍼 단백질은 동형이합체 혹은 이형이합체를 형성하며 promoter 영역에 결합하여 전사조절에 중요한 역할을 한다. 세포의 전사인자 ATF2는 ATF/CRE site에 결합하며 특히 선택적인 interfamily 이형이량체를 형성함으로써 전사 조절에 있어서 다양한 메카니즘을 제공할 수 있다. 본 연구에서는 ATF2 cDNA를 6xHis를 가진 expression vector에 subcloning하여 E.cnli BL2l에서 발현시켰다. 6xHis tag은 nickel-chelating chromatography를 가능하게 하였다 발현된 ATF2는 In vitro binding pull-down assay에서 동형이합체를 이를 뿐만 아니라 AP-1 그룹의 인자들과 선택적인 이형이합체를 형성함을 보여 주었다. BATF와는 강하게 결합하였으며 c-Jun과도 안정된 이합체를 형성하였다. 그러나 c-Fos와는 이합체를 형성하지 않으므로서 AP-1그룹 내에서도 이합체 형성이 선택적으로 이루어짐을 알 수 있다.

• Journal of Korean Neurosurgical Society
• /
• 제64권2호
• /
• pp.189-197
• /
• 2021

Objective : This study aims to investigate the relationship between aneurysm wall enhancement and clinical rupture risks based on the magnetic resonance vessel wall imaging (MR-VWI) quantitative methods. Methods : One hundred and eight patients with 127 unruptured aneurysms were prospectively enrolled from Feburary 2016 to October 2017. Aneurysms were divided into high risk (≥10) and intermediate-low risk group (<10) according to the PHASES (Population, Hypertension, Age, Size of aneurysm, Earlier SAH history from another aneurysm, Site of aneurysm) scores. Clinical risk factors, aneurysm morphology, and wall enhancement index (WEI) calculated using 3D MR-VWI were analyzed and compared. Results : In comparison of high-risk and intermediated-low risk groups, univariate analysis showed that neck width (4.5±3.3 mm vs. 3.4±1.7 mm, p=0.002), the presence of wall enhancement (100.0% vs. 62.9%, p<0.001), and WEI (1.6±0.6 vs. 0.8±0.8, p<0.001) were significantly associated with high rupture risk. Multivariate regression analysis revealed that WEI was the most important factor in predicting high rupture risk (odds ratio, 2.6; 95% confidence interval, 1.4-4.9; p=0.002). The receiver operating characteristic (ROC) curve analysis can efficiently differentiate higher risk aneurysms (area under the curve, 0.780; p<0.001) which have a reliable WEI cutoff value (1.04; sensitivity, 0.833; specificity, 0.67) predictive of high rupture risk. Conclusion : Aneurysms with higher rupture risk based on PHASES score demonstrate increased neck width, wall enhancement, and the enhancement intensity. Higher WEI in unruptured aneurysms has a predictive value for increased rupture risk.

• 한국미생물·생명공학회지
• /
• 제50권4호
• /
• pp.563-573
• /
• 2022

Xanthomonas arboricola pv. juglandis (Xaj) is a globally important bacterial pathogen of walnut trees that causes substantial economic losses in commercial walnut production. Although prophages are common in bacterial plant pathogens and play important roles in bacterial diversity and pathogenicity, there has been limited investigation into the distribution and function of prophages in Xaj. In this study, we identified and characterized 13 predicted prophages from the genomes of 12 Xaj isolates from around the globe. These prophages ranged in length from 11.8 kb to 51.9 kb, with between 11-75 genes and 57.82-64.15% GC content. The closest relatives of these prophages belong to the Myoviridae and Siphoviridae families of the Caudovirales order. The phylogenetic analysis allowed the classification of the prophages into five groups. The gene constitution of these predicted prophages was revealed via Roary analysis. Amongst 126 total protein groups, the most prevalent group was only present in nine prophages, and 22 protein groups were present in only one prophage (singletons). Also, bioinformatic analysis of the 13 identified prophages revealed the presence of 431 genes with an average length of 389.7 bp. Prokka annotation of these prophages identified 466 hypothetical proteins, 24 proteins with known function, and six tRNA genes. The proteins with known function mainly comprised prophage integrase IntA, replicative DNA helicase, tyrosine recombinase XerC, and IS3 family transposase. There was no detectable insertion site specificity for these prophages in the Xaj genomes. The identified Xaj prophage genes, particularly those of unknown function, merit future investigation.

• Journal of Microbiology and Biotechnology
• /
• 제33권3호
• /
• pp.387-397
• /
• 2023

Cytochrome P450 (CYP) is a heme-containing enzyme that catalyzes hydroxylation reactions with various substrate molecules. Steroid hydroxylases are particularly useful for effectively introducing hydroxyl groups into a wide range of steroids in the pharmaceutical industry. This study reports a newly identified CYP steroid hydroxylase (BaCYP106A6) from the bacterium Bacillus sp. and characterizes it using an in vitro enzyme assay and structural investigation. Bioconversion assays indicated that BaCYP106A1 catalyzes the hydroxylation of progesterone and androstenedione, whereas no or low conversion was observed with 11β-hydroxysteroids such as cortisol, corticosterone, dexamethasone, and prednisolone. In addition, the crystal structure of BaCYP106A6 was determined at a resolution of 2.8 Å to investigate the configuration of the substrate-binding site and understand substrate preference. This structural characterization and comparison with other bacterial steroid hydroxylase CYPs allowed us to identify a unique Arg295 residue that may serve as the key residue for substrate specificity and regioselectivity in BaCYP106A6. This observation provides valuable background for further protein engineering to design commercially useful CYP steroid hydroxylases with different substrate specificities.

• Investigative Magnetic Resonance Imaging
• /
• 제3권2호
• /
• pp.159-166
• /
• 1999

Purpose : To evaluate the effect of rotational correlation time (${\tau}_R$) and the possible related changes of other parameters, ${\tau}_M,{\;}{\tau}_S,{\;}and{\;}(\tau}_V$ of gadolinium (Gd) chelate on T1 relaxation enhancement in two pool model. Materials and Methods : The NMRD (Nuclear Magnetic Relaxation Dispersion) profiles were simulated from 0.02 MHz to 800 MHz proton Larmor frequency for different values of rotational correlation times based on Solomon-Bloembergen equation for inner-sphere relaxation enhancement. To include both unbound pool (pool A) and bound pool (pool B), the relaxivity was divided by contribution from unbound pool and bound pool. The rotational correlation time for pool A was fixed at the value of 0.1 ns, which is a typical value for low molecular weight complexes such as Gd-DTPA in solution and ${\tau}_R$ for pool B was changed from 0.1 ns to 20 ns to allow the slower rotation by binding to macromolecule. The fractional factor of was also adjusted from 0 to 1.0 to simulate different binding ratios to macromolecule. Since the binding of Gd-chelate to macromolecule cab alter the electronic environment of Gd ion and also the degree of bulk water access to hydration site of Gd-chelate, the effects of these parameters were also included. Results : The result shows that low field profiles, ranged from 0.02 to 40 MHz, and dominated by contribution from bound pool, which is bound to macromolecule regardless of binding ratios. In addition, as more Gd-chelate bound to macromolecule, sharp increase of relaxivity at higher field occurs. The NMRD profiles for different values of ${\tau}_S$ show the enormous increase of low field profile whereas relaxivity at high field is not affected by ${\tau}_S$. On the other hand, the change in ${\tau}$V does not affect low field profile but strongly in fluences on both inflection fie이 and the maximum relaxivity value. The results shows a fluences on both inflection field and the maximum relaxivity value. The results shows a parabolic dependence of relaxivity on ${\tau}_M$. Conclusion : Binding of Gd-chelate to a macromolecule causes slower rotational tumbling of Gd-chelate and would result in relaxation enhancement, especially in clinical imaging field. However, binding to macromolecule can change water enchange rate (${\tau}_M$) and electronic relaxation ($T_le$) vis structural deformation of electron environment and the access of bulk water to hydration site of metal-chelate. The clinical utilities of Gd-chelate bound to macromolecule are the less dose requirement, the tissue specificity, and the better perfusion and intravascular agents.

• 한국식품과학회지
• /
• 제23권1호
• /
• pp.31-36
• /
• 1991

고온, 알칼리성 Bacillus sp. F204의 CMCase 유전자를 pUC19의 HindIII부위에 연결하여 전이된 E.coli 형질전환체 중 2개의 재조합 플라스미드 즉, pBC191과 pBC192를 선발하였는데, 이들은4.6 Kb와 5.8 Kb HindIII 절편을 각각 함유하고 있었다. pBC191의 4.6 Kb HindIII 절편을 BamHI, EcoRI, KpnI, PvuII 부위가 각각 1개씩 존재하였다. Dioxigenin-labeled deoxyuridin-triphosphate에 4.6 Kb 절편을 표식한 것을 probe로 하여 상동성을 검정한 결과 모균주와 강한상동성이 없었고, 면역학적 실험에서도 Bacillus sp. F204 유래임이 인정되었다. pBC191의 4.6 Kb 절편을 E.coli의 발현 벡타인 pKK223-3과 Bacillus vector인 pGR71에 연결시켜 구축한 pKC231과 pGC711은 각각 pBC191에 비하여 효소활성이 3.2배와 2.8배정도 증가되었으며, 그리고 E.coli에서는 대부분 세포내와 periplasmic 분획에서 검출되었다. 기질 특이성을 조사한 결과에 의하면 pBC191과 pBC192는 CMCase gene을 코딩하고 있는 것으로 나타났다.

• Radiation Oncology Journal
• /
• 제29권3호
• /
• pp.191-198
• /
• 2011

Purpose: Although the role of squamous cell carcinoma antigen (SCC-Ag) as a predictive and prognostic factor for uterine cervical cancer has been identified in previous studies, 1) the effective patient group of screening for recurrence with SCC-Ag, 2) the relationship between SCC-Ag and recurrence site, and 3) the relationship between the change of SCC-Ag and treatment outcome or recurrence have not been described. Materials and Methods: The study included 506 patients with histologically proven uterine cervical cancer between January 1994 and December 2010. We determining the serum SCC-Ag level before treatment and after treatment, and conducted a retrospective review of the patients' records. We evaluated the sensitivity and specificity of SCC-Ag for the detection of tumor recurrence by comparing biochemical recurrence with clinical recurrence. Results: The pretreatment SCC-Ag level and the proportion of patients over 1.5 ng/mL were higher in poor prognostic patient group. In the univariate and multivariate analysis, pretreatment SCC-Ag showed a statistically significant correlation with tumor size, International Federation of Gynecology and Obstetrics (FIGO) stage, pathology. In patients with biochemical recurrence vs. those without, 5-year DFS and OS were 27.6 vs. 92.7% (p ${\leq}$ 0.001) and 53.7 vs. 92.5% (p ${\leq}$ 0.001), respectively. Conclusion: Our study reconfirmed the known function of pretreatment SCC-Ag, but could not confirm the function of biochemical response as a predictive factor for treatment and as a prognostic factor. There was no statistically significant relationship between SCC-Ag level and recurrence site. We confirmed the role of SCC-Ag as a follow-up tool for recurrence of disease and which patient groups SCC-Ag was more useful for.

• 미생물학회지
• /
• 제32권1호
• /
• pp.84-90
• /
• 1994

Adenosine deaminase (ADA)의 여러 기질과 억제물질의 반응 속도론적 상수가 Aspergillusoryzae의 세포내 효소인 ADA의 활성자리에 어떻게 부착하고 어떤 요인을 필요로 하는지를 알기위해 측적되어졌다. kcat/$K_m$값에 의하면 조사된 기질로 작용하는 화합물 중에 3'-deoxyadenosine이 가장 좋은 기질로 작용하는 것으로 밝혀졌다. 몇 개의 유사체가 억제물질로 조사되었는데 purine riboside가 $3.7{\times}10^{-5}$M의 값 $K_i$값을 가지고 가장 강한 억베물질로 나타났다. Adenine은 기질로도 억제물질로도 작용을 못하므로 adenine의 N-9 위치의 ribose가 효소에 부착하는데 중요하다는 것을 시사하고 있다. 또 ADA는 6-chloropurine riboside(6-CPR)의 dechlorination을 촉매화하여 inosine과 Cl이온을 생성한다. 6-CPR의 ADA에 대한 기질 특이성은 정상 기질인 adenine의 0.86%로 측정되었다. ADA의 경쟁적 억제물질인 purine riboside는 비슷한 $K_i$값을 가지고 dechlorination도 억제하므로 deamination과 dechlorination 반응은 효소의 부착자리를 공유하고 있다고 생각되어진다. SH기에 작용하는 화합물중 수은제인 p-chloromercuribenzoate(PCMB), mersalyl acid, $HgCl_2$는 효소의 deamination 반응을 억제했다. Mersalyl acid에 의해 활성이 억제된 ADA는 thiol reagent인 dithiothreitol이나 2-mercaptoethanol에 의해 활성이 회복되지만 PCMB에 의해 억제된 효소는 회복되지 않았다. 각 수은제들이 억제물질로 작용할 때 $K_i$값과 억제양상이 측정되었는데 모두 경쟁적 방해를 보였다. $K_i$값은 10mM 인산완충용액에서 측정한 것이 100 mM 인산완충용액에서 측정한 것보다 훨씬 낮아 인산기가 기질이 아니어도 효소의 부착에 큰 영향을 미치는 것을 보여주고 있다.

• Parasites, Hosts and Diseases
• /
• 제37권3호
• /
• pp.163-169
• /
• 1999

House dust mite allergens have been well established as sensitizing agents that are important in the induction of allergic diseases. In order to analyze epitopes of the allergen and to develop a quantitative method of the allergen exposure, monoclonal antibodies against a recombinant Der p 2 (rDer p 2), one of the major allergens of Dermatophogoides pteronyssinus, were produce. Four monoclonal antibodies produced wee species-specific and did not cross-react to the D. farinae crude extract. Two of the monoclonal antibodies were found to be IgG1 and the others were IgM. For the analysis of epitopes, a Der p 2 cDNA encoding 126 amino acids (aa) was dissected into three fragments with several overlapping peptides, A (aa residues 1-49), B (44-93), and C fragment (84-126). Three monoclonal antibodies showed reactivities to the recombinant B fragment and to the full-length rDer p 2, but one monoclonal antibody reacted only with the full-length rDer p 2. Two-site capture ELISA was developed using two different monoclonal antibodies for quantitating Der p2 in house dust. The sensitivity limit was 4ng/ml with rDer p2 and $8{\;}\mu\textrm{g}/ml$ with the d. pteronyssinus crude extract. The result suggested that the assay using monoclonal antibodies against rDer p2 could be useful for the environmental studies and for the standardization of mite allergen extracts.

• 헤리티지:역사와 과학
• /
• 제47권4호
• /
• pp.92-105
• /
• 2014

인골과 인골 주변 토양에 분포하는 세균의 군집구조를 비교하기 위해 부여 오수리 큰독골 유적에서 발굴된 조선시대 회곽묘 인골 중 상대적으로 시료 상태가 좋지 않은 4호 인골과 상태가 양호한 5호 인골 및 주변 토양에서 DNA를 추출하였다. 추출한 DNA의 16S rDNA 염기서열 분석을 수행한 결과, 4호 인골에서 구축된 319개 클론은 ${\alpha}$, ${\beta}$, ${\gamma}$-Proteobacteria, Acidobacteria, Actinobacteria, Planctomycetes, Chloroflexi, Chlorobi, Bacteroidetes, Firmicutes 그리고 novel gene group 등 총 11개의 계통군이 확인되었다. 인골 주변 토양에서 구축된 462개 콜론은 ${\alpha}$, ${\beta}$, ${\gamma}$, ${\delta}$-Proteobacteria, Acidobacteria, Actinobacteria, Bacteroidetes, Verrucomicrobia, Planctomycetes, Chloroflexi, Chlorobi, Firmicutes, Thermodesulfobacteria, Fibrobacteres, Gemmatimonadetes, Verrucomicrobia 그리고 novel gene group 등 총 16개 계통군이 확인되었다. 5호 인골에서 구축된 271개 클론은 ${\alpha}$, ${\gamma}$-Proteobacteria, Acidobacteria, Actinobacteria, Planctomycetes, Chloroflexi, Bacteroidetes, Firmicutes 그리고 novel gene group 등 총 10개의 계통군이 확인되었으며, 인골 주변 토양에서 구축된 497개 클론은 ${\alpha}$, ${\beta}$, ${\gamma}$-Proteobacteria, Actinobacteria, Acidobacteria, Chloroflexi, Firmicutes, Gemmatimonadetes, Planctomycetes, Bacteroidetes 그리고 Verrucomicrobia 등 총 11개 계통군으로 확인되었다. 4호, 5호의 모든 시료에서 Actinobacteria 계통군이 가장 높은 비율을 차지하고 있으며, ${\alpha}$-Proteobacteria 계통군 또한 높은 비율을 차지하는 것으로 분석되었다. 인골은 주변 토양 세균의 군집에 의해 광범위하게 오염되어 있다는 것이 확인되었으며, 본 결과는 인골의 보존과 관리를 위한 중요 자료로 활용될 것이다.