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71.
Hyung Kwoun Kim Hwa Jung Choi Myung Hee Kim Cheon Bae Sohn Tae Kwang Oh 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2002,1583(2):205-212
A lipase-producing Bacillus pumilus strain (B26) was isolated from a soil sample collected in Korea. The cloned gene showed that the lipase B26 composed of a 34-amino-acid signal sequence and a 181-amino-acid mature part corresponding to a molecular mass (Mr) of 19,225. Based on the Mr and the protein sequence, the lipase B26 belongs to the lipase family I.4. The optimum temperature and pH of the purified enzyme were 35 °C and 8.5, respectively. The lipase B26 showed a ‘Ca2+-independent thermostability and catalytic activity’. These are novel properties observed for the first time in lipase B26 among all bacterial lipases and correspond with the suggestion that this enzyme had no Ca2+-binding motif around the catalytic His156 residue. This enzyme seems to be a true lipase based on the experimental results that it could hydrolyze various long-chain triglycerides (C14–C18) and triolein (C18:1) and that it showed a typical interfacial activation mechanism toward both tripropionin and p-nitrophenyl butyrate. 相似文献
72.
Doo Hyun Chung Kyeong Cheon Jung Weon Seo Park Im-Soon Lee Weon Jin Choi Chong-Jae Kim Seong Hoe Park Youngmee Bae 《Molecules and cells》2001,10(6):642-646
To induce proper immune responses, T lymphocytes require two types of stimuli, antigen-specific and costimulatory signals. Among costimulatory molecules, CD28-engagement promotes the survival and proliferation of both naive and memory T cells. In addition, it is now believed that Fas may play a role in T cell activation in the human system. It is, however, controversial whether Fas can act as a costimulatory signal in the murine system. Thus, we investigated fundamental differences in the capacity to induce proliferation of T cells between Fas and CD28 in mice. Fas-mediated T cell proliferation was observed only with a full mitogenic dose of anti-CD3 antibodies, whereas CD28 engagement was able to enhance T cell proliferation in the presence of a suboptimal level of anti-CD3 antibody. Furthermore, Fas-engaged T cells showed faster response in the upregulation of CD25 and CD69 expression than CD28-engaged ones. Here, we report that Fas might play a role in mature T cell activation in the mouse system through a different mechanism from that in CD28 costimulation. 相似文献
73.
Johan C. Sunryd Banyoon Cheon Jill B. Graham Kristina M. Giorda Rafael A. Fissore Daniel N. Hebert 《The Journal of biological chemistry》2014,289(23):16085-16099
The endoplasmic reticulum (ER) is organized in part by adapter proteins that nucleate the formation of large protein complexes. Tetratricopeptide repeats (TPR) are well studied protein structural motifs that support intermolecular protein-protein interactions. TMTC1 and TMTC2 were identified by an in silico search as TPR-containing proteins possessing N-terminal ER targeting signal sequences and multiple hydrophobic segments, suggestive of polytopic membrane proteins that are targeted to the secretory pathway. A variety of cell biological and biochemical assays was employed to demonstrate that TMTC1 and TMTC2 are both ER resident integral membrane proteins with multiple clusters of TPR domains oriented within the ER lumen. Proteomic analysis followed by co-immunoprecipitation verification found that both proteins associated with the ER calcium uptake pump SERCA2B, and TMTC2 also bound to the carbohydrate-binding chaperone calnexin. Live cell calcium measurements revealed that overexpression of either TMTC1 or TMTC2 caused a reduction of calcium released from the ER following stimulation, whereas the knockdown of TMTC1 or TMTC2 increased the stimulated calcium released. Together, these results implicate TMTC1 and TMTC2 as ER proteins involved in ER calcium homeostasis. 相似文献
74.
75.
Suresh Paudel Xiao Min Srijan Acharya Daulat Bikram Khadka Goon Yoon Kyeong-Man Kim Seung Hoon Cheon 《Bioorganic & medicinal chemistry》2018,26(20):5538-5546
Two series of 4-arylpiperazine- and 4-benzylpiperidine naphthyl ethers were designed based on structure-activity relationship (SAR) and docking model of reported monoamine neurotransmitters reuptake inhibitors. The compounds were synthesized in 3-simple steps and their biological activities were evaluated. Several compounds were proven to be potent inhibitors of serotonin and norepinephrine reuptake. Computer docking was performed to study the interaction of the most potent compound 35 with human serotonin transporter. The results of the analyses suggest that 4-arylpiperazine- and 4-benzylpiperidine naphthyl ethers might be promising antidepressants worthy of further studies. 相似文献
76.
Seung-Hoon Kang Hong-Yeol Choi Ji-Suk Cho Su-Hwan Cheon Ji-Yeon Kim Brian B. Kim Dong-Il Kim 《Biotechnology and Bioprocess Engineering》2018,23(2):218-227
A reproducible method for cryopreservation of transgenic rice cells (Oryza sativa L. cv. Dongjin) producing recombinant human cytotoxic T lymphocyte-associated antigen 4-immunoglobulin (hCTLA4Ig) has been established. Here, we assessed recovery media and investigated recombinant protein homogeneity after long-term preservation. For recovery of cryopreserved transgenic rice cells, AA medium was suitable in terms of both morphology and production of hCTLA4Ig. There were no differences in cell growth, sugar consumption, and hCTLA4Ig production between non-cryopreserved and cryopreserved cells for up to 1 month. hCTLA4Ig produced from cryopreserved cells was identical that of hCTLA4Ig from non-cryopreserved cells, as determined by analysis of its molecular weight and isoforms. For long-term preservation, cell viability was stably maintained at 61% for 26 months. In conclusion, these results demonstrate the possibility for reproducible cryocell-banking of transgenic rice cells without changes in the characteristics of cells and target proteins. 相似文献
77.
Eun-Jin Cheon Bon-Hoon Koo Joong-Hyun Choi 《Applied psychophysiology and biofeedback》2016,41(1):103-110
The purpose of this study was to evaluate the effect of neurofeedback on depressive symptoms and electrophysiological disturbances in patients with major depressive disorder. We recruited participants suffering from depression to evaluate efficacy of left prefrontal beta with alpha/theta training. An 8-week, prospective, open-label study was undertaken. Twenty participants were recruited. The treatment protocol was twice or three times a week training of beta at F3 with alpha/theta at Pz for 8 weeks. When every visit, patients were received beta training for 30 min, and then alpha/theta training for 30 min. Baseline, 4 and 8 week scores of; the Hamilton rating scale for Depression (HAM-D), the Hamilton rating scale for Anxiety (HAM-A), the Beck Depression Inventory (BDI)-II, the Beck Anxiety Inventory (BAI), Clinical global impression-severity (CGI-S), and pre- and post-treatment resting state EEGs were compared. Interhemispheric alpha power asymmetry (A score) was computed for homologous sites F3–F4. Pre- and post-training clinical assessments revealed significant improvements in HAM–D, HAM-A, BDI, and CGI-S scores. Cumulative response rates by HAM-D were 35.0 and 75.0 % at 4 and 8 weeks, respectively, corresponding cumulative remission rates by HAM-D were 15.0 and 55.0 %, respectively. No significant differences were found between pre- and post-treatment A score. Neurofeedback treatment could improve depressive symptoms significantly. In addition, anxiety symptoms and clinical illness severity decreased significantly after neurofeedback treatment. Despite its several limitations, such as, small sample size and lack of a control group, this study suggested neurofeedback has significant effects in patients with major depressive disorder. 相似文献
78.
Background
Non-biological signal (or noise) has been the bane of microarray analysis. Hybridization effects related to probe-sequence composition and DNA dye-probe interactions have been observed in differential methylation hybridization (DMH) microarray experiments as well as other effects inherent to the DMH protocol. 相似文献79.
Omar JM Hamza Mecky IN Matee Mainen J Moshi Elison NM Simon Ferdinand Mugusi Frans HM Mikx Wim H van Palenstein Helderman Antonius JMM Rijs André JAM van der Ven Paul E Verweij 《BMC microbiology》2008,8(1):135
Background
In Tanzania, little is known on the species distribution and antifungal susceptibility profiles of yeast isolates from HIV-infected patients with primary and recurrent oropharyngeal candidiasis. 相似文献80.
Jeanine A Verbunt Henk AM Seelen Feljandro P Ramos Bernard HM Michielsen Wim L Wetzelaer Martine Moennekens 《BMC neurology》2008,8(1):7