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11.
Anabaena sensory rhodopsin (ASR) is an archaeal-type rhodopsin found in eubacteria. The gene encoding ASR forms a single operon with ASRT (ASR transducer) that is a 14 kDa soluble protein, suggesting that ASR functions as a photochromic sensor by activating the soluble transducer. One of the characteristics of ASR is that the formation of the M intermediate accompanies a proton transfer from the Schiff base to Asp217 in the cytoplasmic side [Shi, L., Yoon, S. R., Bezerra, A. G., Jr., Jung, K. H., and Brown, L. S. (2006) J. Mol. Biol. 358, 686-700], in remarkable contrast to other archaeal-type rhodopsins such as a light-driven proton-pump, bacteriorhodopsin (BR). In this study, we applied low-temperature Fourier transform infrared (FTIR) spectroscopy to the all- trans form of ASR at 170 K, and compared the structural changes in the L intermediate with those of BR. The ASR L minus ASR difference spectra were essentially similar to those for BR, suggesting common structures for the L state in ASR and BR. On the other hand, unique CO stretching bands of a protonated carboxylic acid were observed at 1722 (+) and 1703 (-) cm (-1) at pH 5 and 7, and assigned to Glu36 by use of mutants. Glu36 is located at the cytoplasmic side, and the distance from the Schiff base is about 20 A. This result shows the structural changes at the cytoplasmic surface in ASR L. pH-dependent frequency change was also observed for a water stretching vibration, suggesting that the water molecule is involved in a hydrogen-bonding network with Glu36 and Asp217. Unique hydrogen-bonding network in the cytoplasmic domain of ASR will be discussed. 相似文献
12.
Suyoung Yoon Sung-Eun Kim Jong Hyun Kim Ina Yoon Phuong-Thao Tran Jihyae Ann Changhoon Kim Woong Sub Byun Sangkook Lee Sunghoon Kim Jiyoun Lee Jeewoo Lee 《Bioorganic & medicinal chemistry》2019,27(6):1099-1109
Leucyl-tRNA synthetase (LRS) plays an important role in amino acid-dependent mTORC1 signaling, which is known to be associated with cellular metabolism and proliferation. Therefore, LRS-targeting small molecules that can suppress mTORC1 activation may provide an alternative strategy to current anticancer therapy. In this work, we developed a library of leucyladenylate sulfate analogues by extensively modifying three different pharmacophoric regions comprising adenine, ribose and leucine. Several effective compounds were identified by cell-based mTORC1 activation assays and further tested for anticancer activity. The selected compounds mostly exhibited selective cytotoxicity toward five different cancer cell lines, supporting the hypothesis that the LRS-mediated mTORC1 pathway is a promising alternative target to current therapeutic approaches. 相似文献
13.
WEHI-231 and Bal 17 B cell lines are representative models for immature and mature B cells, respectively. Their regulation of cytosolic Ca(2+) concentration ([Ca(2+)](c)) was compared using fura-2 fluorescence ratiometry. The ligation of B cell antigen receptor (BCR) by anti-IgM antibody induced a slow but large increase of [Ca(2+)](c) in WEHI-231 cells while not in Bal 17 cells. The thapsigargin-induced store-operated Ca(2+) entry (SOCE) of Bal 17 cells reached a steady state which was blocked by 2-aminoethoxydiphenyl borate (2-APB). On the contrary, the thapsigargin-induced SOCE of WEHI-231 cells increased continuously, which was accelerated by 2-APB. The increase of [Ca(2+)](c) by BCR ligation was also enhanced by 2-APB in WEHI-231 cells while blocked in Bal 17 cells. The Mn(2+) quenching study showed that the thapsigargin-, or the BCR ligation-induced Ca(2+) influx pathway of WEHI-231 was hardly permeable to Mn(2+). The intractable increase of [Ca(2+)](c) may explain the mechanism of BCR-driven apoptosis of WEHI-231 cells, a well-known model of clonal deletion of autoreactive immature B cells. 相似文献
14.
15.
Koung Jin Suh June-Won Cheong Inho Kim Hyeoung-Joon Kim Dong-Yeop Shin Youngil Koh Sung-Soo Yoon Yoo Hong Min Jae-Sook Ahn Yeo-Kyeoung Kim Yun-Gyoo Lee Jeong-Ok Lee Soo-Mee Bang Yeung-Chul Mun Chu-Myoung Seong Yong Park Byung-Soo Kim Junshik Hong Jinny Park Jae Hoon Lee Sung-Yong Kim Hong Ghi Lee 《PloS one》2016,11(11)
Chromosomal translocations are rare in myelodysplastic syndrome (MDS) and their impact on overall survival (OS) and response to hypomethylating agents (HMA) is unknown. The prognostic impact of the revised International Prognostic Scoring System (IPSS-R) and for chromosomal translocations was assessed in 751 patients from the Korea MDS Registry. IPSS-R effectively discriminated patients according to leukaemia evolution risk and OS. We identified 40 patients (5.3%) carrying translocations, 30 (75%) of whom also fulfilled complex karyotype criteria. Translocation presence was associated with a shorter OS (median, 12.0 versus 79.7 months, P < 0.01). Multivariate analysis demonstrated that translocations (hazard ratio [HR] 1.64 [1.06–2.63]; P = 0.03) as well as age, sex, IPSS-R, and CK were independent predictors of OS. In the IPSS-R high and very high risk subgroup (n = 260), translocations remained independently associated with OS (HR 1.68 [1.06–2.69], P = 0.03) whereas HMA treatment was not associated with improved survival (median OS, 20.9 versus 21.2 months, P = 0.43). However, translocation carriers exhibited enhanced survival following HMA treatment (median 2.1 versus 12.4 months, P = 0.03). Our data suggest that chromosomal translocation is an independent predictor of adverse outcome and has an additional prognostic value in discriminating patients with MDS having higher risk IPSS-R who could benefit from HMA treatment. 相似文献
16.
Jae-Seong Lee Ryeo-Ok Kim Jae-Sung Rhee Jeonghoon Han Dae-Sik Hwang Beom-Soon Choi Chang Joo Lee Yong-Dal Yoon Jong-Sung Lim Young-Mi Lee Gyung Soo Park Atsushi Hagiwara Ik-Young Choi 《Hydrobiologia》2011,662(1):65-75
The monogonont rotifer, Brachionus ibericus (S type), is considered to be a promising model species for developmental biology, evolution, and environmental genomics. In an attempt to accelerate the molecular understanding of B. ibericus, we sequenced 680.5 Mb of genomic DNA using the genome sequencer GS-FLX-Titanium. We obtained 2,062,621 reads (average read length 329.9 bp) and 145,418 contigs (total contigs length 125.7 Mb) after excluding small reads (less than 200 bp) from the assembly, and finally obtained 10,133 unigenes (E value ?? 9.00E?04) after non-redundant (NR) BLAST search. In this article, we summarize the genomic DNA sequences of B. ibericus and discuss their potential use in the study of reproductive biology, endocrinology, environmental genomics, and ecotoxicological studies, and for providing insight into the genetic basis of mechanisms such as egg formation, antioxidant stress defense, and xenobiotic metabolism. 相似文献
17.
A Gram-negative, motile and rod-shaped bacterial strain, G-M8T, which was isolated from seashore sand around a seaweed farm at Geoje island in South Korea, was characterized taxonomically. It grew optimally at 30–37 °C, at pH 7.0–8.0 and in presence of 2 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain G-M8T joined the cluster comprising the type strains of Ruegeria atlantica and Ruegeria lacuscaerulensis, showing 97.5 % sequence similarity, by a bootstrap resampling value of 85.8 %. It exhibited 16S rRNA gene sequence similarity values of 95.4–96.7 % to the type strains of the other Ruegeria species. Strain G-M8T exhibited the highest gyrB sequence similarity value (88.5 %) to the type strain of R. lacuscaerulensis. Strain G-M8T contained Q-10 as the predominant ubiquinone and C18:1 ω7c as the predominant fatty acid. The polar lipid profile of strain G-M8T was similar to that of R. atlantica KCTC 12424T. The DNA G+C content of strain G-M8T was 64.6 mol% and its mean DNA–DNA relatedness values with R. atlantica KCTC 12424T and R. lacuscaerulensis KCTC 2953T were 18 ± 5.3 and 10 ± 3.6 %, respectively. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, demonstrated that strain G-M8T is distinguished from other Ruegeria species. On the basis of the data presented, strain G-M8T (=KCTC 23960T = CCUG 62412T) represents a novel species of the genus Ruegeria, for which the name Ruegeria arenilitoris sp. nov. is proposed. 相似文献
18.
Hye Jin Yoo Soon Young Hwang Ho Cheol Hong Hae Yoon Choi Sae Jeong Yang Dong Seop Choi Sei Hyun Baik Matthias Blüher Byung-Soo Youn Kyung Mook Choi 《PloS one》2013,8(2)
Objective
Progranulin and C1q/TNF-related protein-3 (CTRP3) were recently discovered as novel adipokines which may link obesity with altered regulation of glucose metabolism, chronic inflammation and insulin resistance.Research Design and Methods
We examined circulating progranulin and CTRP3 concentrations in 127 subjects with (n = 44) or without metabolic syndrome (n = 83). Furthermore, we evaluated the relationship of progranulin and CTRP3 levels with inflammatory markers and cardiometabolic risk factors, including high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), estimated glomerular filtration rate (eGFR), and adiponectin serum concentrations, as well as carotid intima-media thickness (CIMT).Results
Circulating progranulin levels are significantly related with inflammatory markers, hsCRP (r = 0.30, P = 0.001) and IL-6 (r = 0.30, P = 0.001), whereas CTRP3 concentrations exhibit a significant association with cardiometabolic risk factors, including waist circumference (r = −0.21), diastolic blood pressure (r = −0.21), fasting glucose (r = −0.20), triglyceride (r = −0.34), total cholesterol (r = −0.25), eGFR (r = 0.39) and adiponectin (r = 0.26) levels. Serum progranulin concentrations were higher in patients with metabolic syndrome than those of the control group (199.55 [179.33, 215.53] vs. 185.10 [160.30, 204.90], P = 0.051) and the number of metabolic syndrome components had a significant positive correlation with progranulin levels (r = 0.227, P = 0.010). In multiple regression analysis, IL-6 and triglyceride levels were significant predictors of serum progranulin levels (R 2 = 0.251). Furthermore, serum progranulin level was an independent predictor for increased CIMT in subjects without metabolic syndrome after adjusting for other cardiovascular risk factors (R 2 = 0.365).Conclusions
Serum progranulin levels are significantly associated with systemic inflammatory markers and were an independent predictor for atherosclerosis in subjects without metabolic syndrome.Trial Registration
ClinicalTrials.gov NCT01668888相似文献19.
Thoracic ultrasound (TUS) is an easy-to-use imaging modality that aids physicians in the differential diagnosis of respiratory diseases. However, no data exist on the TUS findings of acute eosinophilic pneumonia (AEP) or their clinical utility in patients with AEP. Thus, we performed an observational study on TUS findings and their clinical utility for follow-up in patients with AEP. We prospectively screened patients who visited the emergency department for acute respiratory symptoms at the Armed Forces Capital Hospital in South Korea between February 2014 and July 2014. Of them, patients suspected to have AEP underwent an etiological investigation, including flexible bronchoscopy with bronchoalveolar lavage and TUS, and we evaluated TUS findings and serial changes on TUS during the treatment course compared with those from chest radiographs. In total, 22 patients with AEP were identified. The TUS examinations reveled that all patients exhibited multiple diffuse bilateral B-lines and lung sliding, with (n = 5) or without pleural effusion, which was consistent with alveolar-interstitial syndrome. B-line numbers fell during the course of treatment, as the lines became thinner and fainter. A-lines were evident in 19 patients on day 7 of hospitalization, when B-lines had disappeared in 13 patients, and all pleural effusion had resolved. All patients exhibited complete ultrasonic resolution by day 14, along with clinicoradiological improvement. Chest radiographs of five patients taken on day 7 seemed to show complete resolution, but several abnormal B-lines were evident on TUS performed the same day. As a result, our data show common TUS findings of AEP and suggest that AEP may be included as a differential diagnosis when multiple diffuse bilateral B-lines with preserved lung sliding are identified on a TUS examination in patients with acute symptoms, and that TUS is a useful modality for evaluating the treatment response in patients with AEP. 相似文献
20.
Song MS Moon HJ Kwon HI Pascua PN Lee JH Baek YH Woo KJ Choi J Lee S Yoo H Oh I Yoon Y Rho JB Sung MH Hong SP Kim CJ Choi YK 《Journal of microbiology (Seoul, Korea)》2012,50(3):478-488
The threat of a highly pathogenic avian influenza (HPAI) H5N1 virus causing the next pandemic remains a major concern. In this study, we evaluated the immunogenicity and efficacy of an inactivated whole-virus H5N1 pre-pandemic vaccine (MG1109) formulated by Green Cross Co., Ltd containing the hemagglutinin (HA) and neuraminidase (NA) genes of the clade 1 A/Vietnam/1194/04 virus in the backbone of A/Puerto Rico/8/34 (RgVietNam/04xPR8/34). Administration of the MG1109 vaccine (2-doses) in mice and ferrets elicited high HI and SN titers in a dose-dependent manner against the homologous (RgVietNam/04xPR8/34) and various heterologous H5N1 strains, (RgKor/W149/06xPR8/34, RgCambodia/04xPR8/34, RgGuangxi/05xPR8/34), including a heterosubtypic H5N2 (A/Aquatic bird/orea/W81/05) virus. However, efficient cross-reactivity was not observed against heterosubtypic H9N2 (A/Ck/Korea/H0802/08) and H1N1 (PR/8/34) viruses. Mice immunized with 1.9 μg HA/dose of MG1109 were completely protected from lethal challenge with heterologous wild-type HPAI H5N1 A/EM/Korea/W149/06 (clade 2.2) and mouse-adapted H5N2 viruses. Furthermore, ferrets administered at least 3.8 μg HA/dose efficiently suppressed virus growth in the upper respiratory tract and lungs. Vaccinated mice and ferrets also demonstrated attenuation of clinical disease signs and limited virus spread to other organs. Thus, this vaccine provided immunogenic responses in mouse and ferret models even against challenge with heterologous HPAI H5N1 and H5N2 viruses. Since the specific strain of HPAI H5N1 virus that would potentially cause the next outbreak is unknown, pre-pandemic vaccine preparation that could provide cross-protection against various H5 strains could be a useful approach in the selection of promising candidate vaccines in the future. 相似文献