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41.
Eiichiro Kan Yohei Katsuyama Jun-ichi Maruyama Koichi Tamano Yasuji Koyama 《Bioscience, biotechnology, and biochemistry》2019,83(7):1372-1381
The filamentous fungus Aspergillus oryzae was recently used as a heterologous host for fungal secondary metabolite production. Here, we aimed to produce the plant polyketide curcumin in A. oryzae. Curcumin is synthesized from feruloyl-coenzyme A (CoA) and malonyl-CoA by curcuminoid synthase (CUS). A. oryzae expressing CUS produced curcumin (64 μg/plate) on an agar medium containing feruloyl-N-acetylcysteamine (a feruloyl-CoA analog). To increase curcumin yield, we attempted to strengthen the supply of malonyl-CoA using two approaches: enhancement of the reaction catalyzed by acetyl-CoA carboxylase (ACC), which produces malonyl-CoA from acetyl-CoA, and inactivation of the acetyl-CoA-consuming sterol biosynthesis pathway. Finally, we succeeded in increasing curcumin yield sixfold by the double disruption of snfA and SCAP; SnfA is a homolog of SNF1, which inhibits ACC activity by phosphorylation in Saccharomyces cerevisiae and SCAP is positively related to sterol biosynthesis in Aspergillus terreus. This study provided useful information for heterologous polyketide production in A. oryzae. 相似文献
42.
43.
Yohei Takahashi Haruaki Ishiyama Takaaki Kubota Jun’ichi Kobayashi 《Bioorganic & medicinal chemistry letters》2010,20(14):4100-4103
A new β-carboline alkaloid, eudistomidin G (1), has been isolated from the Okinawan marine tunicate Eudistoma glaucus, and the structure was elucidated from spectroscopic data. Furthermore, the structure of eudistomidin B (2), which has been isolated from the same tunicate, was revised from 2a to 2b by detailed analyses of spectroscopic data. Asymmetric synthesis of the revised structure (2b) of eudistomidin B (2) and its (1S,10S)-diastereomer (2c) has been accomplished with the Noyori catalytic asymmetric hydrogen-transfer reaction. The absolute configuration of eudistomidin B (2) was confirmed to be 2b possessing (1R,10S)-configuration, from comparison of the 1H NMR data, CD spectra, [α]D values, and HPLC analysis of 2b, 2c, and natural eudistomidin B. 相似文献
44.
MOTIVATION: A comprehensive gene expression database is essential for computer modeling and simulation of biological phenomena, including development. Development is a four-dimensional (4D; 3D structure and time course) phenomenon. We are constructing a 4D database of gene expression for the early embryogenesis of the nematode Caenorhabditis elegans. As a framework of the 4D database, we have constructed computer graphics (CG), into which we will incorporate the expression data of a number of genes at the subcellular level. However, the assignment of 3D distribution of gene products (protein, mRNA), of embryos at various developmental stages, is both difficult and tedious. We need to automate this process. For this purpose, we developed a new system, named SPI after superimposing fluorescent confocal microscopic data onto a CG framework. RESULTS: The scheme of this system comprises the following: (1) acquirement of serial sections (40 slices) of fluorescent confocal images of three colors (4',6'-diamino-2-phenylindole (DAPI) for nuclei, indodicarbocyanine (Cy-3) for the internal marker, which is a germline-specific protein POS-1 and indocarbocyanine (Cy-5) for the gene product to be examined); (2) identification of several features of the stained embryos, such as contour, developmental stage and position of the internal marker; (3) selection of CG images of the corresponding stage for template matching; (4) superimposition of serial sections onto the CG; (5) assignment of the position of superimposed gene products. The Snakes algorithm identified the embryo contour. The detection accuracy of embryo contours was 92.1% when applied to 2- to 28-cell-stage embryos. The accuracy of the developmental stage prediction method was 81.2% for 2- to 8-cell-stage embryos. We manually judged only the later stage embryos because the accuracy for embryos at the later stages was unsatisfactory due to experimental noise effects. Finally, our system chose the optimal CG and performed the superposition and assignment of gene product distribution. We established an initial 4D gene expression database with 56 maternal gene products. AVAILABILITY: This system is available at http://anti.lab.nig.ac.jp/spi/ and http://anti.lab.nig.ac.jp/4ddb/ 相似文献
45.
Inoue Y Miyawaki K Terasawa T Matsushima K Shinmyo Y Niwa N Mito T Ohuchi H Noji S 《Gene expression patterns : GEP》2004,4(6):725-731
We report that Gryllus bimaculatus dachshund (Gbdac), a cricket homologue of Drosophila dachshund (Dmdac), is expressed in the developing eye and brain. During brain development, Gbdac was first expressed in the medial head region, corresponding to a part of developing protocephalic region, and expressed in the primordial and adult Kenyon cells. During eye development, Gbdac was first expressed in the lateral head region, becoming to the eye primordium and a part of the deutocerebrum. Then, Gbdac was expressed in the posterior region of the eye primordium, prior to the formation of compound eyes. The expression domain shifted to the anterior domain concomitantly with the movement of morphogenetic furrows. Gbdac was also expressed in the developing optic lobes during differentiation of the retina. These expression patterns were compared with those of Dmdac. We found that although developmental processes of the Gryllus eye and brain differ from those of the Drosophila ones, the expression patterns of Gbdac are essentially similar to those of the Dmdac. 相似文献
46.
Expression of Fibroblast growth factor 19 (Fgf19) during chicken embryogenesis and eye development, compared with Fgf15 expression in the mouse 总被引:2,自引:0,他引:2
Kurose H Bito T Adachi T Shimizu M Noji S Ohuchi H 《Gene expression patterns : GEP》2004,4(6):687-693
The normal development of eyes relies on proper signaling through Fibroblast growth factor (FGF) receptors, but the source and identity of cognate ligands have remained largely unknown. We have found that Fgf19 is expressed in the developing chicken retina. In situ hybridization discloses dynamic expression patterns for Fgf19 in the optic vesicle, lens primordia and retinal horizontal cells. Overall expression pattern of Fgf19 during chicken embryogenesis was also examined: Fgf19 is expressed in the regions associated with cranial placodes induction, boundary regions of rhombomeres, somites, specific groups of neural cells in midbrain, hindbrain, and those derived from epibranchial placodes, and the apical ectodermal ridge of limb buds. Expression pattern of the Fgf19-orthologous gene Fgf15 was further examined in the mouse developing eye. Fgf15 is expressed in the optic vesicle, a subset of progenitor cells of neural retina, and emerging ganglion and amacrine cells during retinogenesis. 相似文献
47.
Seto Y Nakajima H Suto A Shimoda K Saito Y Nakayama KI Iwamoto I 《Journal of immunology (Baltimore, Md. : 1950)》2003,170(2):1077-1083
Allergic inflammation is mediated by Th2 cell-derived cytokines, including IL-4, IL-5, and IL-13, and down-regulated by IFN-gamma and IL-12. Tyk2 is a member of the Janus family of protein tyrosine kinases and is activated by a variety of cytokines: IFN-alphabeta, IL-6, IL-10, IL-12, and IL-13. In this study, we investigated the role of Tyk2 in the regulation of Ag-induced Th cell differentiation and Ag-induced allergic inflammation in the airways using Tyk2-deficient (Tyk2(-/-)) mice. When splenocytes were stimulated with antigenic peptide, IL-12-mediated Th1 cell differentiation was decreased, but IL-4-mediated Th2 cell differentiation was increased in Tyk2(-/-) mice. In vivo, Ag-specific IgE and IgG1 production was increased, but Ag-specific IgG2a production was decreased in Tyk2(-/-) mice as compared with those in control mice. In addition, Ag-induced eosinophil and CD4(+) T cell recruitment, as well as the production of Th2 cytokines in the airways, was increased in Tyk2(-/-) mice. Adoptive transfer experiments revealed that CD4(+) T cells were responsible for the enhanced Ag-induced eosinophil recruitment in Tyk2(-/-) mice. In contrast, although the level of IL-13 was increased in the airways of Tyk2(-/-) mice after Ag inhalation, the number of goblet cells, as well as Muc5ac mRNA expression, was decreased in Tyk2(-/-) mice. Together, these results indicate that Tyk2 plays a bilateral role in the regulation of allergic inflammation in the airways: Tyk2 plays a role in the down-regulation of Th2 cell-mediated Ab production and eosinophil recruitment in the airways by regulating Th1/Th2 balance toward Th1-type, while Tyk2 is necessary for the induction of IL-13-mediated goblet cell hyperplasia in the airways. 相似文献
48.
Hirano S Tominaga Y Ichinoe A Ushijima Y Tsuchimoto D Honda-Ohnishi Y Ohtsubo T Sakumi K Nakabeppu Y 《The Journal of biological chemistry》2003,278(40):38121-38124
To evaluate the antimutagenic role of a mammalian mutY homolog, namely the Mutyh gene, which encodes adenine DNA glycosylase excising adenine misincorporated opposite 8-oxoguanine in the template DNA, we generated MUTYH-null mouse embryonic stem (ES) cells. In the MUTYH-null cells carrying no adenine DNA glycosylase activity, the spontaneous mutation rate increased 2-fold in comparison with wild type cells. The expression of wild type mMUTYH or mutant mMUTYH protein with amino acid substitutions at the proliferating cell nuclear antigen binding motif restored the increased spontaneous mutation rates of the MUTYH-null ES cells to the wild type level. The expression of a mutant mMUTYH protein with an amino acid substitution (G365D) that corresponds to a germ-line mutation (G382D) found in patients with multiple colorectal adenomas could not suppress the elevated spontaneous mutation rate of the MUTYH-null ES cells. Although the recombinant mMUTYH(G365D) purified from Escherichia coli cells had a substantial level of adenine DNA glycosylase activity as did wild type MUTYH, no adenine DNA glycosylase activity was detected in the MUTYH-null ES cells expressing the mMUTYH(G365D) mutant protein. The germ-line mutation (G382D) of the human MUTYH gene is therefore likely to be responsible for the occurrence of a mutator phenotype in these patients. 相似文献
49.
Watanabe M Miyake K Yanae K Kataoka Y Koizumi S Endo T Ozaki A Iijima S 《Journal of biochemistry》2002,131(2):183-191
A group B streptococcus, Streptococcus agalactiae type Ib, produces a high-molecular-weight polysaccharide consisting of the following pentasaccharide repeating unit: -->4)-[alpha-D-NeupNAc-(2-->3)-beta-D-Galp-(1-->3)-beta-D-GlcpNAc-(1-->3)]-beta-D-Galp-(1-->4)-beta-D-Glcp-(1-->. The type-specific capsular polysaccharide (CP) synthesis (cps) genes of this strain were cloned and analyzed. A cloned 10-kb DNA fragment contained cpsIbE to L and neu (neuraminic acid synthesis gene) B. Comparison of the gene products with those of S. agalactiae type Ia, which has a similar but distinct CP, showed that the translation products of cpsIa and cpsIb genes exhibited very high homology except for those of cpsJ and K. In the type Ia strain, cpsIaJ encodes beta1,4-galactosyltransferase, which catalyzes the transfer of galactose as the fourth monosaccharide of the sugar repeating unit. In the type Ib CP, this galactose forms a beta1,3-linkage to GlcNAc. The low homology between the type Ia and Ib CpsJs seems to reflect this difference. By enzymatic activity measurement, the cpsIbJ product was found to display beta1,3-galactosyltransferase activity. Furthermore, hydrophobic cluster analysis clarified the similarities and differences of the structures in N-terminal regions, including the DXD motif, between the galactosyltransferases. 相似文献
50.
A case of acute gastric mucosal lesions associated with Helicobacter heilmannii infection 总被引:3,自引:0,他引:3
Yoshimura M Isomoto H Shikuwa S Osabe M Matsunaga K Omagari K Mizuta Y Murase K Murata I Kohno S 《Helicobacter》2002,7(5):322-326
A 69-year-old-woman presented with acute epigastric pain, nausea, vomiting and heartburn. Endoscopy disclosed acute gastric mucosal lesions including mucosal edema, erosions, and ulcers with blood crusts in the antrum. Touch cytology and histological assessment obtained from the affected mucosa revealed acute neutrophilic gastritis and single longer and more coiled organisms than Helicobacter pylori, suggesting Helicobacter heilmannii. Electron micropragh confirmed the characteristic morphology. Despite a positive rapid urease test, H. pylori was not isolated by culture or detected by histology and Gram smears. Based on these findings, a diagnosis of acute gastric mucosal lesions associated with H. heilmannii infection was established. This was successfully treated with a 2-week triple therapy consisting of lansoprazole, clarithromycin and metronidazole with persistent endoscopic and histological remission. This is a rare case of H. heilmannii-associated acute gastric mucosal lesions, diagnosed by morphology using touch cytology and histology. The patient might benefit from antimicrobial treatment employing the regimen effective for H. pylori. 相似文献