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991.
Iwata K Ogata S Okumura K Taguchi H 《Bioscience, biotechnology, and biochemistry》2003,67(5):1132-1135
Water-soluble vitamin, niacin, and its related compounds were examined for their differentiation-inducing activity in human promyelocytic leukemia cells (HL-60). Among the compounds, which inhibited cell proliferation measured by MTT assay, isonicotinic acid, nicotinamide N-oxide, and nicotinamide induced NBT reducing activity. HL-60 cells were differentiated into granulocyte-like cells by these compounds, judging from morphological changes and loss of nonspecific esterase activity. The differentiation-inducing activity of water-soluble vitamin and its related compounds suggest that these compounds may be applicable for medical use. 相似文献
992.
Aoki H Uda I Tagami K Furuya Y Endo Y Fujimoto K 《Bioscience, biotechnology, and biochemistry》2003,67(5):1018-1023
A cultivation procedure for the preparation of a new tempeh-like fermented soybean containing a high level of gamma-aminobutyric acid was developed. Steamed soybeans were incubated aerobically with Rhizopus microsporus var. oligosporus IFO 8631 for 20 h, and then anaerobically incubated for 5 h by replacement of the atmosphere with nitrogen. The GABA content in the aerobically fermented soybeans was about 30 mg per 100 g dry fermented soybeans, while the anaerobically cultivation was about 370 mg/100 g dry fermented soybeans. The incubation with several strains of Rhizopus species showed that all of R. microsporus var. oligosporus and R. oryzae examined accumulated GABA in the anaerobically fermented soybeans. In particular, R. microsporus var. oligosporus IFO 32002 and IFO 32003 showed the highest content of GABA (1,740 mg/100 g dry fermented soybeans and 1,500 mg/100 g dry fermented soybeans, respectively). Moreover, the free protein amino acids increased greatly in the fermented soybeans during the anaerobic cultivation. 相似文献
993.
ERECTA, an LRR receptor-like kinase protein controlling development pleiotropically affects resistance to bacterial wilt 总被引:13,自引:0,他引:13
Godiard L Sauviac L Torii KU Grenon O Mangin B Grimsley NH Marco Y 《The Plant journal : for cell and molecular biology》2003,36(3):353-365
Bacterial wilt, one of the most devastating bacterial diseases of plants worldwide, is caused by Ralstonia solanacearum and affects many important crop species. We show that several strains isolated from solanaceous crops in Europe are pathogenic in different accessions of Arabidopsis thaliana. One of these strains, 14.25, causes wilting symptoms in A. thaliana accession Landsberg erecta (Ler) and no apparent symptoms in accession Columbia (Col-0). Disease development and bacterial multiplication in the susceptible Ler accession depend on functional hypersensitive response and pathogenicity (hrp) genes, key elements for bacterial pathogenicity. Genetic analysis using Ler x Col-0 recombinant inbred lines showed that resistance is governed by at least three loci: QRS1 (Quantitative Resistance to R. solanacearum) and QRS2 on chromosome 2, and QRS3 on chromosome 5. These loci explain about 90% of the resistance carried by the Col-0 accession. The ERECTA gene, which encodes a leucine-rich repeat receptor-like kinase (LRR-RLK) and affects development of aerial organs, is dimorphic in our population and lies close to QRS1. Susceptible Ler plants transformed with a wild-type ERECTA gene, and the LER line showed increased disease resistance to R. solanacearum as indicated by reduced wilt symptoms and impaired bacterial growth, suggesting unexpected cross-talk between resistance and developmental pathways. 相似文献
994.
Adachi R Shulman AI Yamamoto K Shimomura I Yamada S Mangelsdorf DJ Makishima M 《Molecular endocrinology (Baltimore, Md.)》2004,18(1):43-52
The vitamin D receptor (VDR), initially identified as a nuclear receptor for 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3], regulates calcium metabolism, cellular proliferation and differentiation, immune responses, and other physiological processes. Recently, secondary bile acids such as lithocholic acid (LCA) were identified as endogenous VDR agonists. To identify structural determinants required for VDR activation by 1alpha,25(OH)2D3 and LCA, we generated VDR mutants predicted to modulate ligand response based on sequence homology to pregnane X receptor, another bile acid-responsive nuclear receptor. In both vitamin D response element activation and mammalian two-hybrid assays, we found that VDR-S278V is activated by 1alpha,25(OH)2D3 but not by LCA, whereas VDR-S237M can respond to LCA but not to 1alpha,25(OH)2D3. Competitive ligand binding analysis reveals that LCA, but not 1alpha,25(OH)2D3, effectively binds to VDR-S237M and both 1alpha,25(OH)2D3 and LCA bind to VDR-S278V. We propose a docking model for LCA binding to VDR that is supported by mutagenesis data. Comparative analysis of the VDR-LCA and VDR-1alpha,25(OH)2D3 structure-activity relationships should be useful in the development of bile acid-derived synthetic VDR ligands that selectively target VDR function in cancer and immune disorders without inducing adverse hypercalcemic effects. 相似文献
995.
Growth promotion of mycelia of the Matsutake mushroom Tricholoma matsutake by D-isoleucine 总被引:5,自引:0,他引:5
Kawagishi H Hamajima K Takanami R Nakamura T Sato Y Akiyama Y Sano M Tanaka O 《Bioscience, biotechnology, and biochemistry》2004,68(11):2405-2407
Mycelial growth of the Matsutake mushroom (Tricholama matsutake) was much slower than that of the other mushroom species. We found that the addition of D-isoleucine to the culture medium strikingly promoted mycelia growth. The other amino acids tested had no effect on this growth promotion. 相似文献
996.
Takikawa H Hosoe S Ueda K Sasaki M 《Bioscience, biotechnology, and biochemistry》2004,68(9):1961-1965
The first synthesis of (+/-)-robinlin (1), a novel homo-monoterpene with strong bioactivity in the brine shrimp lethality test, was achieved by starting from 3-isobutyloxy-2,6,6-trimethyl-2-cyclohexen-1-one (2). 相似文献
997.
Phospholipase C-beta 2 (PLC-beta 2) is a key enzyme in mammalian taste signal transduction. To analyze the taste system in fishes at molecular level, we cloned mfplc-beta 2 as a medaka fish homologue of PLC-beta 2. In situ hybridization analysis revealed that mfplc-beta 2 is expressed in the lip and branchial region where chemosensory tissues are distributed. Immunohistochemical detection of nerve fibers near the mfplc-beta 2 positive cells suggests the characteristic of peripheral sensory cells. These results suggest that mfplc-beta 2 is expressed in the gustatory sensory cells of medaka. This may provide a molecular basis for the taste reception at multiple tissues in fish species. 相似文献
998.
Erdenebaatar J Bayarsaikhan B Yondondorj A Watarai M Shirahata T Jargalsaikhan E Kawamoto K Makino S 《Microbiology and immunology》2004,48(8):571-577
Brucellosis is an important zoonosis, and serological surveillance is essential to its control. However, cross-reactions of attenuated live cells of Brucella abortus strain S-19 and B. melitensis strain Rev-1 with Yersinia enterocolitica O9 or vaccinated animal sera interfere with accurate serological diagnosis by the Rose Bengal test (RBT). Therefore, we used ELISA with sarcosine extracts from the virulent B. abortus strain 544 to eliminate false-positives among RBT positive-sera. A total of 697 serum samples were collected in Mongolia from humans and animals in 23 nomadic herds. The herds were classified into three groups as brucellosis-endemic (BE), brucellosis-suspected (BS), or Brucella-vaccinated (BV). The number of 295 animals (43.0%) was positive by RBT, but 206 (69.8%) of these were positive according to ELISA; therefore, 30.2% of the RBT-positive sera were found to be false positives. The false positive samples for RTB represent 4.1%, 27.4%, and 68.2% of the animals from the BE, BS, and BV herds, respectively. In addition, 32% of RBT-positive human sera were also false positives. Thus, our ELISA would be more specific than RTB and useful for epidemiological surveillance for brucellosis. 相似文献
999.
Proteins induced in rice by auxin and zinc were determined by proteome analysis. Cultured suspension cells of rice were treated with 2,4-dichlorophenoxyacetic acid and ZnSO4 and then proteins were separated by two-dimensional polyacrylamide gel electrophoresis; seven proteins were found to be induced by auxin and zinc. Of these seven, methylmalonate-semialdehyde dehydrogenase (MMSDH) was elevated by treatment with auxin alone. MMSDH was detected in cultured suspension cells, root and leaf sheath, but not in leaf blades. MMSDH responded to auxin and gibberellin, but did not respond to brassinolide and cytokinin. Furthermore, the amount of MMSDH in slr1, a constitutive gibberellin response mutant, was 2-fold that of wild type. MMSDH mRNA and protein were stimulated in root formation induced by auxin and/or zinc over a 4-week period. These results suggest that MMSDH may be necessary for root formation in rice induced by auxin and/or zinc.Abbreviations BA
6-Benzylaminopurine
- BL
Brassinolide
- CBB
Coomassie Brilliant Blue
- 2,4-D
2,4-Dichlorophenoxyacetic acid
- GA
Gibberellic acid
- IAA
Indole-3-acetic acid
- MALDI-TOF MS
Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry
- MMSDH
Methylmalonate-semialdehyde dehydrogenase
- 2D-PAGE
Two-dimensional polyacrylamide gel electrophoresis
- PVDF
Polyvinylidene difluoride 相似文献
1000.
Ashiuchi M Shimanouchi K Nakamura H Kamei T Soda K Park C Sung MH Misono H 《Applied and environmental microbiology》2004,70(7):4249-4255
For the first time, we succeeded in synthesizing in vitro poly-gamma-glutamate (PGA) with high molecular masses (>1,000 kDa) by the use of enzyme-associated cell membranes from Bacillus subtilis subsp. chungkookjang. The activity for PGA synthesis, however, was readily lost in the presence of critical concentrations of detergents tested in micelles. The optimum pH for the reaction was found to be approximately 7.0. We examined the effects of some divalent cations on PGA synthesis and found that Mg(2+) was essential in catalysis and that Zn(2+) additionally boosted the activity. In contrast, Fe(2+) and Ca(2+) acted as inhibitors. Mn(2+) did not apparently influence the in vitro formation of PGA. DL-Glutamate (D isomer content, 60 to 80%) apparently served as the best substrate; d-Glutamate was preferable to the L isomer as a substrate. When D- and L-glutamate were used for the reaction, the elongated chains of PGAs were composed of the D- and L-isomers, respectively. Our results suggest that the stereochemical properties of enzymatically synthesized PGAs substantially depend on the stereochemistry (DL ratio) of glutamate as the substrate. Furthermore, genetic analysis indicated that all the pgsB, -C, and -A gene products, which are responsible for PGA production by B. subtilis cells, were also indispensable for enzymatic PGA synthesis. 相似文献