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101.
Tatsuji Sakamoto Yuya Tsujitani Keiko Fukamachi Yuya Taniguchi Hideshi Ihara 《Applied microbiology and biotechnology》2010,86(4):1115-1124
Two distinct extracellular bifunctional proteins with β-L-arabinopyranosidase/α-D-galactopyranosidase activities were purified
from the culture filtrate of Fusarium oxysporum 12S. The molecular masses of the enzymes were estimated to be 55 (Fo/AP1) and 73 kDa (Fo/AP2) by SDS-PAGE. They hydrolyzed
both p-nitrophenyl β-L-arabinopyranoside and p-nitrophenyl α-D-galactopyranoside with different specificities. Fo/AP1 also showed low activity towards α-D-galactopyranosyl
oligosaccharides such as raffinose. Interestingly, both enzymes hydrolyzed larch wood arabinogalactan (releasing arabinose)
but not carob galactomannan, which has α-D-galactopyranosyl side chains. When larch wood arabinogalactan was incubated with
excess Fo/AP1 or Fo/AP2, both enzymes released approximately 10% of the total arabinose in the substrate. cDNAs encoding Fo/AP1
and Fo/AP2 (Foap1 and Foap2) were isolated by in vitro cloning. The coding sequences of Foap1 and Foap2 genes were 1,647 and 1,620 bp in length and encode polypeptides of 549 and 540 amino acids, respectively. The N-terminal
halves of both proteins had high similarity to putative conserved domains of the melibiase superfamily (Pfam account number
02065). The deduced amino acid sequences of the two enzymes indicate that they belong to glycosyl hydrolase family 27. Moreover,
the C-terminal regions of both proteins contain a putative family 35 carbohydrate-binding module. 相似文献
102.
Tsuchiyama M Sakamoto T Fujita T Murata S Kawasaki H 《Biochimica et biophysica acta》2006,1760(7):1071-1079
Commercially available enzyme preparations were screened for enzymes that have a high ability to catalyze direct ester-synthesis of ferulic acid with glycerol. Only a preparation, Pectinase PL "Amano" produced by Aspergillus niger, feruloylated glycerol under the experimental conditions. The enzyme responsible for the esterification was purified and characterized. This enzyme, called FAE-PL, was found to be quite similar to an A. niger ferulic acid esterase (FAE-III) in terms of molecular mass, pH and temperature optima, substrate specificity on synthetic substrates, and the N-terminal amino acid sequence. FAE-PL highly catalyzed direct esterification of ferulic acid and sinapinic acid with glycerol. FAE-PL could feruloylate monomeric sugars including arabinose, fructose, galactose, glucose, and xylose. We determined the suitable conditions for direct esterification of ferulic acid with glycerol to be as follows: 1% ferulic acid in the presence of 85% glycerol and 5% dimethyl sulfoxide at pH 4.0 and 50 degrees C. Under these conditions, 81% of ferulic acid could be converted to 1-glyceryl ferulate, which was identified by (1)H-NMR. The ability of 1-glyceryl ferulate to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals was higher than that of the anti-oxidant butyl hydroxytoluene. 相似文献
103.
Fujiwara T Mori Y Chu DL Koyama Y Miyata S Tanaka H Yachi K Kubo T Yoshikawa H Tohyama M 《Molecular and cellular biology》2006,26(6):2273-2285
HuD is an RNA-binding protein that has been shown to induce neuronal differentiation by stabilizing labile mRNAs carrying AU-rich instability elements. Here, we show a novel mechanism of arginine methylation of HuD by coactivator-associated arginine methyltransferase 1 (CARM1) that affected mRNA turnover of p21cip1/waf1 mRNA in PC12 cells. CARM1 specifically methylated HuD in vitro and in vivo and colocalized with HuD in the cytoplasm. Inhibition of HuD methylation by CARM1 knockdown elongated the p21cip1/waf1 mRNA half-life and resulted in a slow growth rate and robust neuritogenesis in response to nerve growth factor (NGF). Methylation-resistant HuD bound more p21cip1/waf1 mRNA than did the wild type, and its overexpression upregulated p21cip1/waf1 protein expression. These results suggested that CARM1-methylated HuD maintains PC12 cells in the proliferative state by committing p21cip1/waf1 mRNA to its decay system. Since the methylated population of HuD was reduced in NGF-treated PC12 cells, downregulation of HuD methylation is a possible pathway through which NGF induces differentiation of PC12 cells. 相似文献
104.
105.
Tatsuji Chuman Masahiro Kohno Kunio Kato Masao Noguchi Hiroko Nomi Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(9):2019-2023
A stereoselective synthesis of erythro-serricornin [(4RS,6R,7S)-4,6-dimethyl-7-hydroxynonan-3-one] was completed starting from l-(+)-tartaric acid. The relative configuration of C(6)-methyl and C(7)-hydroxyl groups in naturally occurring serricornin was threo. 相似文献
106.
Shikibu Muranaka Tomoko Kanno Hirofumi Fujita Hirotsugu Kobuchi Jitsuo Akiyama Tatsuji Yasuda 《Free radical research》2013,47(6):613-621
Mitochondria reduce Cr(VI) to Cr(V) with concomitant generation of reactive oxygen species, thereby exhibiting cytotoxic effects leading to apoptosis in various types of cells. To clarify the mechanism by which Cr(VI) induces apoptosis, we examined the effect of Cr(VI) on Chinese hamster ovary (CHO) cells. Cr(VI) increased cellular levels of ceramide by activating acid sphingomyelinase (ASMase) and inhibiting the phosphorylation of pleckstrin homology domain-containing protein kinase B (Akt). Cr(VI) also induced cyclosporin A- and trifluoperazine-sensitive depolarization of mitochondria and activated caspase-3, 8 and 9, thereby causing fragmentation of cellular DNA. The presence of desipramine, an inhibitor of ASMase, and membrane permeable pCPT-cAMP suppressed the Cr(VI)-induced activation of caspases and DNA fragmentation. These results suggested that accumulation of ceramide play an important role in the Cr(VI)-induced apoptosis of CHO cells through activation of mitochondrial membrane permeability transition. 相似文献
107.
Sakamoto T Ogura A Inui M Tokuda S Hosokawa S Ihara H Kasai N 《Applied microbiology and biotechnology》2011,90(1):137-146
108.
Takeshi Ishikawa Satoshi Kokura Tatsuji Enoki Naoyuki Sakamoto Tetsuya Okayama Mitsuko Ideno Junichi Mineno Kazuko Uno Naohisa Yoshida Kazuhiro Kamada Kazuhiro Katada Kazuhiko Uchiyama Osamu Handa Tomohisa Takagi Hideyuki Konishi Nobuaki Yagi Yuji Naito Yoshito Itoh Toshikazu Yoshikawa 《PloS one》2014,9(1)
Background
Previous studies have demonstrated that less-differentiated T cells are ideal for adoptive T cell transfer therapy (ACT) and that fibronectin CH296 (FN-CH296) together with anti-CD3 resulted in cultured cells that contain higher amounts of less-differentiated T cells. In this phase I clinical trial, we build on these prior results by assessing the safety and efficacy of FN-CH296 stimulated T cell therapy in patients with advanced cancer.Methods
Patients underwent fibronectin CH296-stimulated T cell therapy up to six times every two weeks and the safety and antitumor activity of the ACT were assessed. In order to determine immune function, whole blood cytokine levels and the number of peripheral regulatory T cells were analyzed prior to ACT and during the follow up.Results
Transferred cells contained numerous less-differentiated T cells greatly represented by CD27+CD45RA+ or CD28+CD45RA+ cell, which accounted for approximately 65% and 70% of the total, respectively. No ACT related severe or unexpected toxicities were observed. The response rate among patients was 22.2% and the disease control rate was 66.7%.Conclusions
The results obtained in this phase I trial, indicate that FN-CH296 stimulated T cell therapy was very well tolerated with a level of efficacy that is quite promising. We also surmise that expanding T cell using CH296 is a method that can be applied to other T- cell-based therapies.Trial Registration
UMIN UMIN000001835 相似文献109.
Nakahara T Tominaga K Koseki T Yamamoto M Yamato K Fukuda J Nishihara T 《Cellular signalling》2003,15(2):181-187
Bone morphogenetic proteins, including growth/differentiation factor-5 (GDF-5), are multifunctional cytokines. Recent studies of intracellular signal transduction mechanisms for the transforming growth factor-beta superfamily have focused on Smad proteins. However, scant attention has been given to the mechanism by which GDF-5 exerts its negative growth effect on immunological competent cells. In the present study, we demonstrated that GDF-5 induced cell cycle arrest in the G1 phase before the appearance of apoptosis in mouse B cell hybridoma HS-72 cells, while the ectopic expression of Smad6 and Smad7 in HS-72 cells suppressed the GDF-5-induced G1 cell cycle arrest by abolishing the expression of p21(CIP-1/WAF-1) and hypophosphorylation of retinoblastoma protein. Moreover, we found that Smad6 and Smad7 suppressed GDF-5-induced apoptosis in HS-72 cells. These findings indicated that Smad6 and Smad7 exhibit inhibitory effects toward GDF-5-mediated signaling in B lineage cells. 相似文献
110.
Immunostimulatory activity of polysaccharides isolated from Caulerpa lentillifera on macrophage cells 总被引:3,自引:0,他引:3
Polysaccharides were extracted from Caulerpa lentillifera by treating with water and then purified by size-exclusion chromatography. The purified polysaccharides, termed SP1, were found to be sulfated xylogalactans with a molecular mass of more than 100 kDa. Adding SP1 to murine macrophage RAW 264.7 cells increased the production of nitric oxide (NO) in a dose-dependent manner. NO was found by immunoblotting and RT-PCR analyses to be synthesized by an inducible NO synthase. SP1 caused the degradation of IκB-α and the nuclear translocation of nuclear factor (NF)-κB subunit p65 in macrophage cells. SP1 also increased the phosphorylation of p38 mitogen-activated protein kinase (MAPK). These results demonstrate that SP1 activated macrophage cells via both the NF-κB and p38 MAPK signaling pathways. Moreover, SP1 increased the expression of various genes encoding cytokines, and the phagocytic activity of macrophage cells. These combined results show that SP1 immunostimulated the activity of macrophage cells. 相似文献