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981.
Hee-Sung Bae Wan-Taek Im Yuichi Suwa James M. Lee Sung-Taik Lee Young-Keun Chang 《Archives of microbiology》2009,191(4):329-340
Although, there have been many published bacterial strains aerobically degrading the heterocyclic amine compounds, only one
strain to date has been reported to degrade pyrrolidine under denitrifying conditions. In this study, denitrifying bacteria
degrading pyrrolidine and piperidine were isolated from diverse geological and ecological origins through selective enrichment
procedures. Based on the comparative sequence results of 16S rRNA genes, 30 heterocyclic amine-degrading isolates were grouped
into ten distinct phylotypes belonging to the genera Thauera, Castellaniella, Rhizobium, or Paracoccus of the phylum Proteobacteria. The representative isolates of individual phylotypes were characterized by phylogenetic, phenotypic and chemotaxonomical
traits, and dissimilatory nitrite reductase gene (nirK and nirS). All isolates completely degraded pyrrolidine and piperidine under both aerobic and anaerobic conditions. The anaerobic
degradations were coupled to nitrate reduction. A metabolic pathway for the anaerobic degradation of pyrrolidine was proposed
on the basis of enzyme activities implicated in pyrrolidine metabolism from three isolates. The three key pyrrolidine-metabolizing
enzymes pyrrolidine dehydrogenase, γ-aminobutyrate/α-ketoglutarate aminotransferase, and succinic semialdehyde dehydrogenase,
were induced by heterocyclic amines under denitrifying conditions. They were also induced in cells grown aerobically on heterocyclic
amines, suggesting that the anaerobic degradation of pyrrolidine shares the pathway with aerobic degradation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
982.
Cytotechnology - We found that strawberry extract suppressed immunoglobulin (Ig) E production in vitro and in vivo, and identified glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as one of the IgE... 相似文献
983.
Bone-marrow-derived mesenchymal stem cells (MSCs) can differentiate into a variety of cell types including smooth muscle cells (SMCs). We have attempted to demonstrate that, following treatment with transforming growth factor-beta 1 (TGF-beta1) and ascorbic acid (AA), human bone-marrow-derived MSCs differentiate into the SMC lineage for use in tissue engineering. Quantitative polymerase chain reaction for SMC-specific gene (alpha smooth muscle actin, h1-calponin, and SM22alpha) expression was performed on MSCs, which were cultured with various concentrations of TGF-beta1 or AA. TGF-beta1 had a tendency to up-regulate the expression of SMC-specific genes in a dose-dependent manner. The expression of SM22alpha was significantly up-regulated by 30 muM AA. We also investigated the additive effect of TGF-beta1 and AA for differentiation into SMCs and compared this effect with that of other factors including platelet-derived growth factor BB (PDGF-BB). In addition to SMC-specific gene expression, SMC-specific proteins increased by two to four times when TGF-beta1 and AA were used together compared with their administration alone. PDGF did not increase the expression of SMC-specific markers. MSCs cultured with TGF-beta1 and AA did not differentiate into osteoblasts and adipocytes. These results suggest that a combination of TGF-beta1 and AA is useful for the differentiation of MSCs into SMCs for use in tissue engineering. 相似文献
984.
Conversion of a Signal into Forces for Axon Outgrowth through Pak1-Mediated Shootin1 Phosphorylation
Michinori Toriyama Satoshi Kozawa Yuichi Sakumura Naoyuki Inagaki 《Current biology : CB》2013,23(6):529-534
Highlights? An attractive guidance cue, netrin-1, induces Pak1-mediated shootin1 phosphorylation ? Pak1-mediated shootin1 phosphorylation enhances clutch engagement at growth cones ? Pak1-mediated shootin1 phosphorylation promotes formation of traction forces ? Pak1-mediated shootin1 phosphorylation promotes axon outgrowth 相似文献
985.
Akasaka-Manya K Manya H Endo T 《Biochemical and biophysical research communications》2004,325(1):75-79
Walker-Warburg syndrome (WWS) is an autosomal recessive developmental disorder characterized by congenital muscular dystrophy, brain malformation, and structural eye abnormalities. WWS is due to defects in protein O-mannosyltransferase 1 (POMT1), which catalyzes the transfer of mannose to protein to form O-mannosyl glycans. POMT1 has been shown to require co-expression of another homologue, POMT2, to have activity. In the present study, mutations in POMT1 genes observed in patients with WWS were duplicated by site-directed mutagenesis. The mutant genes were co-expressed with POMT2 in Sf9 cells and assayed for protein O-mannosyltransferase activity. Expression of all mutant proteins was confirmed by Western blot, but the recombinant proteins did not show any protein O-mannosyltransferase activity. The results indicate that mutations in the POMT1 gene result in a defect of protein O-mannosylation in WWS patients. This may cause failure of binding between alpha-dystroglycan and laminin or other molecules in the extracellular matrix and interrupt normal muscular function and migration of neurons in developing brain. 相似文献
986.
1.5 kb mRNA abundantly expressed in rat tumors encodes a 37 kilodalton protein in vitro 总被引:2,自引:0,他引:2
Y Maehara T Fujiyoshi K Takahashi M Yamamoto H Endo 《Biochemical and biophysical research communications》1985,131(2):800-805
A cDNA clone, pAH34, corresponding to a 1.5 kb mRNA present abundantly in various rat tumors was examined for its protein coding capacity. Hybridization-selected RNAs from both poly(A)+ RNAs of a rat ascites hepatoma cell line, AH60C and of normal liver produced a polypeptide of 37 kilo daltons in vitro, but at much higher levels in the AH60C than in the normal rat liver. Two dimensional electrophoresis of the translation product revealed that the pI of this protein was 7.1. Nucleotide sequence analysis of pAH34 showed that the insert of the clone consisted of 462bp and contained the 3' portion of mRNA, including poly(A) stretch with AATAAA signal sequence centered 16 nucleotides upstream, a short untranslated region and an open reading frame corresponding to possibly 67 amino acids of the C-terminal portion. 相似文献
987.
988.
989.
A large-scale production system of N-acetyllactosamine, a core structure of various oligosaccharides, was established by a whole-cell reaction through the combination of recombinant Escherichia coli strains and Corynebacterium ammoniagenes. Two recombinant E. coli strains over-expressed the UDP-Gal biosynthetic genes and the beta-(1-->4)-galactosyltransferase gene of Neisseria gonorrhoeae, respectively. C. ammoniagenes contributed the production of UTP from orotic acid. N-Acetyllactosamine was accumulated at 279 mM (107 g L-1) after a 38 h reaction (2.5 L in volume) starting from orotic acid, D-galactose, and 2-acetamido-2-deoxy-D-glucose. 相似文献
990.
Yoshikuni Goto Yuko Ogawa Hiroki Tsumoto Yuri Miura Takahiro J. Nakamura Kenji Ogawa Yoshihiro Akimoto Hayato Kawakami Tamao Endo Ryohei Yanoshita Masafumi Tsujimoto 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2018,1865(6):874-888
Macrophages secrete endoplasmic reticulum aminopeptidase 1 (ERAP1) in response to lipopolysaccharide (LPS) and interferon (IFN)-γ to enhance their phagocytic and nitric oxide (NO) synthetic activities. In this study, we found that a subset of secreted ERAP1 bound to exosomes released from LPS/IFN-γ-treated murine RAW264.7 macrophages compared to untreated cells. ERAP1-bound exosomes enhanced phagocytic and NO synthetic activities of macrophages more efficiently than free ERAP1 and exosomes derived from untreated cells. Deletion of the exon 10 coding sequence in ERAP1 gene resulted in loss of binding to exosomes. By comparing the activities of exosomes derived from wild-type and ERAP1 gene-deficient RAW264.7 cells, we observed that ERAP1 contributed to the exosome-dependent phagocytosis and NO synthesis of the cells. Upon stimulation of RAW264.7 cells with LPS/IFN-γ, TNF-α, IFN-γ, and CCL3 were also associated with the released exosomes. Analyses of cytokine function revealed that while CCL3 in the exosomes was crucial to the phagocytic activity of RAW264.7 cells, TNF-α and IFN-γ primarily contributed to the enhancement of NO synthesis. These results suggest that treatment with LPS/IFN-γ alters the physicochemical properties of exosomes released from macrophages in order to facilitate association with ERAP1 and several cytokines/chemokines. This leads to exosome-mediated enhancement of macrophage functions. It is possible that packaging effector molecules into exosomes upon inflammatory stimuli, facilitates the exertion of effective pathophysiological functions on macrophages. Our data provide the first evidence that ERAP1 associated with exosomes plays important roles in inflammatory processes via activation of macrophages. 相似文献