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921.
Identification of thermoacidophilic bacteria and a new Alicyclobacillus genomic species isolated from acidic environments in Japan 总被引:1,自引:0,他引:1
Goto K Tanimoto Y Tamura T Mochida K Arai D Asahara M Suzuki M Tanaka H Inagaki K 《Extremophiles : life under extreme conditions》2002,6(4):333-340
Sixty strains of thermoacidophilic bacteria have been isolated from soil and water samples obtained from various acidic environments in Japan. An initial comparative sequence analysis of the hypervariable regions of the 16S rDNA revealed that all strains could be assigned to the Alicyclobacillus acidocaldarius- Alicyclobacillus genomic species 1 group, which could be further subdivided into three clusters (Clusters I-III). On the basis of phenotypic characteristics, chemotaxonomic profiles, and phylogenetic data of six selected strains, five strains were identified as either A. acidocaldarius or Alicyclobacillus genomic species 1; however, one strain (MIH 332) could not be determined to belong to either of these species. 16S rDNA sequence homology values between strain MIH 332 and the reference strains of A. acidocaldarius (ATCC 27009(T)) and Alicyclobacillus genomic species 1 (DSM 11984) were 98.8% and 99.1%, respectively, which were higher than the corresponding similarity between the reference strains (98.4%). On the other hand, DNA-DNA hybridization levels between strain MIH 332 and the reference strains were 39% and 44%, respectively, which were lower than the value between the reference strains (59% or 65%). However, the phenotype of strain MIH 332 was also similar to those of the reference strains, and a typical phenotype could not be found for the strain, thus indicating that the strain may be a new genomic species of A. acidocaldarius, for which the name Alicyclobacillus genomic species 2 is tentatively proposed. The results of this study suggest that A. acidocaldarius and its related species are widely distributed in acidic environments in Japan, with slight regional variations in morphological and genotypic characteristics. 相似文献
922.
Hisashi Koga Shigeki Yuasa Takahiro Nagase Kiyo Shimada Mihoko Nagano Kazuhide Imai Reiko Ohara Daisuke Nakajima Masatoshi Murakami Makoto Kawai Futaba Miki Junji Magae Susumu Inamoto Noriko Okazaki Osamu Ohara 《DNA research》2004,11(4):293-304
The inaugural version of the InGaP database (Integrative Gene and Protein expression database; http://www.kazusa.or.jp/ingap/index.html) is a comprehensive database of gene/protein expression profiles of 127 mKIAA genes/proteins related to hypothetical ones obtained in our ongoing cDNA project. Information about each gene/protein consists of cDNA microarray analysis, subcellular localization of the ectopically expressed gene, and experimental data using anti-mKIAA antibody such as Western blotting and immunohistochemical analyses. KIAA cDNAs and their mouse counterparts, mKIAA cDNAs, were mainly isolated from cDNA libraries derived from brain tissues, thus we expect our database to contribute to the field of neuroscience. In fact, cDNA microarray analysis revealed that nearly half of our gene collection is predominantly expressed in brain tissues. Immunohistochemical analysis of the mouse brain provides functional insight into the specific area and/or cell type of the brain. This database will be a resource for the neuroscience community by seamlessly integrating the genomic and proteomic information about the mouse KIAA genes/proteins. 相似文献
923.
Ikuko Kakizaki Keiichi Takagaki Yasufumi Endo Daisuke Kudo Hitoshi Ikeya Teruzo Miyoshi Bruce A Baggenstoss Valarie L Tlapak-Simmons Kshama Kumari Akio Nakane Paul H Weigel Masahiko Endo 《European journal of biochemistry》2002,269(20):5066-5075
As observed previously in cultured human skin fibroblasts, a decrease of hyaluronan production was also observed in group C Streptococcus equi FM100 cells treated with 4-methylumbelliferone (MU), although there was no effect on their growth. In this study, the inhibition mechanism of hyaluronan synthesis by MU was examined using Streptococcus equi FM100, as a model. When MU was added to a reaction mixture containing the two sugar nucleotide donors and a membrane-rich fraction as an enzyme source in a cell-free hyaluronan synthesis experiment, there was no change in the production of hyaluronan. On the contrary, when MU was added to the culture medium of FM100 cells, hyaluronan production in the isolated membranes was decreased in a dose-dependent manner. However, when the effect of MU on the expression level of hyaluronan synthase was examined, MU did not decrease either the mRNA level of the has operon containing the hyaluronan synthase gene or the protein level of hyaluronan synthase. Solubilization of the enzyme from membranes of MU-treated cells and addition of the exogenous phospholipid, cardiolipin, rescued hyaluronan synthase activity. In the mass spectrometric analysis of the membrane phospholipids from FM100 cells treated with MU, changes were observed in the distribution of only cardiolipin species but not of the other major phospholipid, PtdGro. These results suggest that MU treatment may cause a decrease in hyaluronan synthase activity by altering the lipid environment of membranes, especially the distribution of different cardiolipin species, surrounding hyaluronan synthase. 相似文献
924.
925.
Phosphate Transporter Gene Family of Arabidopsis thaliana 总被引:6,自引:0,他引:6
926.
Daisuke Kyogoku Shigeto Dobata Rui Takashima Teiji Sota 《Journal of evolutionary biology》2023,36(1):309-314
Mating rate optima often differ between the sexes: males may increase their fitness by multiple mating, but for females multiple mating confers little benefit and can often be costly (especially in taxa without nuptial gifts or mala parental care). Sexually antagonistic evolution is thus expected in traits related to mating rates under sexual selection. This prediction has been tested by multiple studies that applied experimental evolution technique, which is a powerful tool to directly examine the evolutionary consequences of selection. Yet, the results so far only partly support the prediction. Here, we provide another example of experimental evolution of sexual selection, by applying it for the first time to the mating behaviour of a seed beetle Callsorobruchus chinensis. We found a lower remating rate in polygamy-line females than in monogamy-line (i.e. no sexual selection) females after 21 generations of selection. Polygamy-line females also showed a longer duration of first mating than monogamy-line females. We found no effect of male evolutionary lines on the remating rate or first mating duration. Though not consistent with the original prediction, the current and previous studies collectively suggest that the observed female-limited responses may be a norm, which is also consistent with the conceptual advances in the last two decades of the advantages and limitations of experimental evolution technique. 相似文献
927.
Hugo Schweke Qifang Xu Gerardo Tauriello Lorenzo Pantolini Torsten Schwede Frédéric Cazals Alix Lhéritier Juan Fernandez-Recio Luis Angel Rodríguez-Lumbreras Ora Schueler-Furman Julia K. Varga Brian Jiménez-García Manon F. Réau Alexandre M. J. J. Bonvin Castrense Savojardo Pier-Luigi Martelli Rita Casadio Jérôme Tubiana Haim J. Wolfson Romina Oliva Didier Barradas-Bautista Tiziana Ricciardelli Luigi Cavallo Česlovas Venclovas Kliment Olechnovič Raphael Guerois Jessica Andreani Juliette Martin Xiao Wang Genki Terashi Daipayan Sarkar Charles Christoffer Tunde Aderinwale Jacob Verburgt Daisuke Kihara Anthony Marchand Bruno E. Correia Rui Duan Liming Qiu Xianjin Xu Shuang Zhang Xiaoqin Zou Sucharita Dey Roland L. Dunbrack Emmanuel D. Levy Shoshana J. Wodak 《Proteomics》2023,23(17):2200323
Reliably scoring and ranking candidate models of protein complexes and assigning their oligomeric state from the structure of the crystal lattice represent outstanding challenges. A community-wide effort was launched to tackle these challenges. The latest resources on protein complexes and interfaces were exploited to derive a benchmark dataset consisting of 1677 homodimer protein crystal structures, including a balanced mix of physiological and non-physiological complexes. The non-physiological complexes in the benchmark were selected to bury a similar or larger interface area than their physiological counterparts, making it more difficult for scoring functions to differentiate between them. Next, 252 functions for scoring protein-protein interfaces previously developed by 13 groups were collected and evaluated for their ability to discriminate between physiological and non-physiological complexes. A simple consensus score generated using the best performing score of each of the 13 groups, and a cross-validated Random Forest (RF) classifier were created. Both approaches showed excellent performance, with an area under the Receiver Operating Characteristic (ROC) curve of 0.93 and 0.94, respectively, outperforming individual scores developed by different groups. Additionally, AlphaFold2 engines recalled the physiological dimers with significantly higher accuracy than the non-physiological set, lending support to the reliability of our benchmark dataset annotations. Optimizing the combined power of interface scoring functions and evaluating it on challenging benchmark datasets appears to be a promising strategy. 相似文献
928.
929.
The action of chlordimeform on the nerve-muscle preparation of the larvae of the waxmoth Galleria mellonella has been studied by means of microelectrodes. Exitatory junction potential evoked by nerve stimulation is reversibly suppressed by 2 × 10?3 M chlordimeform, and spike-like component is abolished. The resting membrane potential of the muscle fibre and the action potential from the nerve terminal are not affected at 5 × 10?3 M chlordimeform. The depolarizing membrane response caused by outward current and the effective membrane resistance are not appreciably affected. It appears that chlordimeform exerts its blocking action on the neuromuscular junction rather than the conductance mechanism of muscle fibre membrane. 相似文献
930.
Hiroshi Inoue Masashi Adachi Nobuya Karimine Shinya Arinaga Hiroaki Ueo Daisuke Korenaga Tsuyoshi Akiyoshi 《Cancer immunology, immunotherapy : CII》1992,35(5):297-301
Summary The intensity of lymphoid cell infiltration and distribution of lymphocyte subsets in tumors were investigated immunohistochemically on tumor tissues obtained from 11 patients with gastric carcinoma, who had been treated with mitomycin C (MMC), 12 mg/m2, i.v. 5 days before operation. The results were compared with those obtained from 24 untreated patients as controls. In the tumor tissues from pretreated patients, the intensity of lymphoid infiltration was not significantly different from that of untreated patients. However, high-grade infiltration of CD4+ cells was observed in 55% of pretreated patients, whereas only 8% of control patients exhibited the high-grade infiltration (P <0.02). Since the CD8+ cell infiltration was not significantly altered, the ratio of CD4+ to CD8+ cells was more frequently estimated to be more than 1 in patients pretreated with MMC, as compared to untreated controls (P <0.02). Further, CD25+ cells in pretreated tumor tissues were more predominant than those in control tumor tissues (P <0.05). These results suggest that MMC administration induces these alterations in lymphocyte subsets in tumor tissue in patients with gastric carcinoma. 相似文献