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151.
Shinji Kondo Akira Shinagawa Tetsuya Saito Hidenori Kiyosawa Itaru Yamanaka Katsunori Aizawa Shiro Fukuda Ayako Hara Masayoshi Itoh Jun Kawai Kazuhiro Shibata Yoshihide Hayashizaki 《Mammalian genome》2001,12(9):673-677
Although the sequencing of the human genome is complete, identification of encoded genes and determination of their structures
remain a major challenge. In this report, we introduce a method that effectively uses full-length mouse cDNAs to complement
efforts in carrying out these difficult tasks. A total of 61,227 RIKEN mouse cDNAs (21,076 full-length and 40,151 EST sequences
containing certain redundancies) were aligned with the draft human sequences. We found 35,141 non-redundant genomic regions
that showed a significant alignment with the mouse cDNAs. We analyzed the structures and compositional properties of the regions
detected by the full-length cDNAs, including cross-species comparisons, and noted a systematic bias of GENSCAN against exons
of small size and/or low GC-content. Of the cDNAs locating the 35,141 genomic regions, 3,217 did not match any sequences of
the known human genes or ESTs. Among those 3,217 cDNAs, 1,141 did not show any significant similarity to any protein sequence
in the GenBank non-redundant protein database and thus are candidates for novel genes.
Received: 18 January 2001 / Accepted: 17 May 2001 相似文献
152.
153.
Transient absorption changes during reduction of quinone in liposomes by external dithionite, in the absence and presence of initially trapped ferricyanide, were matched with absorption spectra of semiquinone and quinone in the blue region. Plastoquinone, ubiquinone-9 and phylloquinone, each having an isoprenoid side chain were compared with trimethyl-p-benzoquinone, ubiquinone-9 and menadione, which lack a long side chain.Semiquinone transients could only be observed by our spectroscopic technique during reduction of quinones lacking the chain. If Triton X-100 was added to the liposomes preparation semiquinone transients were also observed with the isoprenoid quinones. This result is consistent with the view that isoprenoid quinones build domains in the membranes, in which the life time of the semiquinone might be decreased by fast disproportionation, and to which dithionite has limited access. 相似文献
154.
Zhenzhen Wang Miho Shibata Yen Thi Hoang Nguyen Yayoi Hayata Nariaki Nonaka Haruhiko Maruyama Ayako Yoshida 《Parasitology international》2018,67(5):622-626
Ascarid Larva Migrans Syndrome (ascarid LMS) is a clinical syndrome in humans, caused by the migration of animal roundworm larvae such as Toxocara canis, Toxocara cati and Ascaris suum. Humans may acquire infection by ingesting embryonated eggs, or infective larvae of these parasites in contaminated meat and organ meats. To detect these pathogenic contaminations, a novel nested multiplex PCR system was developed. Our novel nested multiplex PCR assay showed specific amplification of T. canis, T. cati and Ascaris spp. Detection limit of the nested multiplex PCR was tested with serial dilution of T. canis, T. cati or A. suum genomic DNA (gDNA) from 100?pg to 100 ag and found to be 10?fg, 1?fg and 100?fg, respectively. When larvae were spiked into chicken liver tissue, DNA of T. canis and A. suum was detected from the liver spiked with a single larva, while the assay required at least 2 larvae of T. cati. Moreover, the ascarid DNA was detected from the liver of mice infected with 100 and 300 eggs of T. canis, T. cati or A. suum. This nested multiplex PCR assay could be useful for the detection of contamination with ascarid larvae in meat and organ meats. 相似文献
155.
We overexpressed and purified 3α-hydroxysteroid dehydrogenase from Pseudomonas sp. B-0831 (Ps3αHSD) and its mutants where the active site residues known as the SYK triad, Ser114, Tyr153, and Lys157, were mutated. Ps3αHSD catalyzes the reaction by using a nucleotide cofactor. The NADH binding affinity of K157A mutant was much lower than that of the wild-type, mainly due to loss of a hydrogen bond. The decreased affinity would result in decreased kcat. Compared to the wild-type, the mutants S114A and Y153F showed higher Km and lower kcat values in both oxidation and reduction reactions. Simultaneous mutation of S114A and Y153F resulted in a significant decrease in kcat relative to the single mutant. These results are supported by the notion that Tyr153 is a catalytic base and Ser114 would be a substitute. Loss of hydrogen bonding with NADH upon the Y153F mutation resulted in increased enthalpy change, partially compensated by increased entropy change. 相似文献
156.
Ayako Sano Reiko Tanaka Kazuko Nishimura Cilmery S. Kurokawa Kunie labuki R. Coelho Marcello Franco Mario Rubens Montenegro Makoto Miyaji 《Mycoscience》1997,38(2):117-122
We have studied the physiological and morphological features of 17 isolates ofParacoccidioides brasiliensis in order to define their phenotypes. The isolates were cultured at room temperature on potato dextrose agar (PDA, Difco)
slants for mycelial growth and in 1% dextrose brain heart infusion agar (BHIA, Difco) at 37°C for the study of yeast forms.
Most mycelial and yeast forms grew well between pH 5.6–9.4. In their response to osmotic pressure the isolates were separated
in three groups: intolerant, intermediate and tolerant. They also varied in carbohydrate assimilation tests, which indicated
important metabolic variation. No clear differences were observed in phenol oxidase tests, KNO3, starch, casein and arbutin assimilation tests. Only 1 of the isolates, Bt-19, had gelatinase activity. No correlation was
observed between the above differences and virulence. Two patterns of growth were observed in the mycelial cultures, glabrous
and cottonous, the latter being correlated with increased virulence for ddY mice. Most yeast forms grew as cerebriform colonies,
but Pb-HC and Bt-19 colonies had a cobblestone-like surface. 相似文献
157.
The absorption and CD spectra of the complexes of poly(L -arginine) (PLA) and azo dyes have been measured in aqueous solution. On complexation, Blue-shifted additional absorption bands were observed. In the wide pH 4–11 range, induced CD was observed at the visible wavelengths corresponding to the blue-shifted absorption bands. The induced CD arose from the dimeric dye molecules bound to PLA in the α-helical structure. When a modified analysis of induced CE is made by the excition chirality method, the origin of the induced CD can be assigned to the dipole coupling. The PLA–dye complexes showed the counterlockwise (negative, S) chirality of the transition dipole moments of dyes. 相似文献
158.
Megumi Narukawa‐Nara Ayako Nakamura Ko Kikuzato Yusuke Kakei Akiko Sato Yuka Mitani Yumiko Yamasaki‐Kokudo Takahiro Ishii Ken‐ichiro Hayashi Tadao Asami Takehiko Ogura Shigeo Yoshida Shozo Fujioka Takashi Kamakura Tsutomu Kawatsu Masanori Tachikawa Kazuo Soeno Yukihisa Shimada 《The Plant journal : for cell and molecular biology》2016,87(3):245-257
We previously reported l ‐α‐aminooxy‐phenylpropionic acid (AOPP) to be an inhibitor of auxin biosynthesis, but its precise molecular target was not identified. In this study we found that AOPP targets TRYPTOPHAN AMINOTRANSFERASE of ARABIDOPSIS 1 (TAA1). We then synthesized 14 novel compounds derived from AOPP to study the structure–activity relationships of TAA1 inhibitors in vitro. The aminooxy and carboxy groups of the compounds were essential for inhibition of TAA1 in vitro. Docking simulation analysis revealed that the inhibitory activity of the compounds was correlated with their binding energy with TAA1. These active compounds reduced the endogenous indole‐3‐acetic acid (IAA) content upon application to Arabidopsis seedlings. Among the compounds, we selected 2‐(aminooxy)‐3‐(naphthalen‐2‐yl)propanoic acid (KOK1169/AONP) and analyzed its activities in vitro and in vivo. Arabidopsis seedlings treated with KOK1169 showed typical auxin‐deficient phenotypes, which were reversed by exogenous IAA. In vitro and in vivo experiments indicated that KOK1169 is more specific for TAA1 than other enzymes, such as phenylalanine ammonia‐lyase. We further tested 41 novel compounds with aminooxy and carboxy groups to which we added protection groups to increase their calculated hydrophobicity. Most of these compounds decreased the endogenous auxin level to a greater degree than the original compounds, and resulted in a maximum reduction of about 90% in the endogenous IAA level in Arabidopsis seedlings. We conclude that the newly developed compounds constitute a class of inhibitors of TAA1. We designated them ‘pyruvamine’. 相似文献
159.
SAD‐B kinase regulates pre‐synaptic vesicular dynamics at hippocampal Schaffer collateral synapses and affects contextual fear memory
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160.
Ogiwara H Ui A Lai MS Enomoto T Seki M 《Biochemical and biophysical research communications》2007,354(1):222-226
Deletion mutants of CHL1 or CTF4, which are required for sister chromatid cohesion, showed higher sensitivity to the DNA damaging agents methyl methanesulfonate (MMS), hydroxyurea (HU), phleomycin, and camptothecin, similar to the phenotype of mutants of RAD52, which is essential for recombination repair. The levels of Chl1 and Ctf4 associated with chromatin increased considerably after exposure of the cells to MMS and phleomycin. Although the activation of DNA damage checkpoint did not affected in chl1 and ctf4 mutants, the repair of damaged chromosome was inefficient, suggesting that Chl1 and Ctf4 act in DNA repair. In addition, MMS-induced sister chromatid recombination in haploid cells, and, more importantly, MMS-induced recombination between homologous chromosomes in diploid cells were impaired in these mutants. Our results suggest that Chl1 and Ctf4 are directly involved in homologous recombination repair rather than acting indirectly via the establishment of sister chromatid cohesion. 相似文献