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91.
M. Nakai Kiyotaka Toshimori Kazuya Yoshinaga Tetsuo Nasu Rex A. Hess 《Cell and tissue research》1998,294(1):145-152
Effects of a single, high dose of orally administered carbendazim (100 mg/kg) on acrosome formation in the early phases of
spermiogenesis were examined by electron microscopy and immunocytochemistry up to day 7.5 post-treatment. No obvious abnormality
of acrosome development was noted in the Golgi phase spermatids on day 1.5 post-treatment. On day 3, step 1 spermatids were
seen in stage III seminiferous tubules. In stage V tubules at this post-treatment interval, direct connections between the
trans-side saccules of the Golgi stacks and the outer acrosomic membranes were observed in step 5 spermatids. Similar direct
connections between these two organelles were also observed in the advanced round spermatids in later stages at days 4.5 and
7.5. On day 4.5, step 1 and 3 spermatids were seen in stage V tubules. On day 7.5, round spermatids with various abnormalities
of acrosome development were observed in stage VII tubules, in addition to the discontinuous and granular acrosomes reported
previously. These features were not observed in testes of control animals. In the immunocytochemical analysis using an antibody
mMN7 that recognizes a protein delivered from the Golgi apparatus to the acrosome, spermatids exposed to carbendazim showed
various abnormal immunostaining patterns in the acrosomes. On the other hand, strong immunoreactivity was observed in the
Golgi saccules connecting to the acrosomes. These results suggest that in testis treated with carbendazim acrosome development
is impaired during the early phases of spermiogenesis, and material supply from the Golgi apparatus to the acrosome is perturbed,
which is a possible cause of the abnormal development.
Received: 31 March 1998 / Accepted: 28 May 1998 相似文献
92.
Kono H Imanishi M Negi S Tatsutani K Sakaeda Y Hashimoto A Nakayama C Futaki S Sugiura Y 《FEBS letters》2012,586(6):918-923
We developed a rational scheme for designing DNA binding proteins. The scheme was applied for a zinc finger protein and the designed sequences were experimentally characterized with high DNA sequence specificity. Starting with the backbone of a known finger structure, we initially calculated amino acid sequences compatible with the expected structure and the secondary structures of the designed fingers were then experimentally confirmed. The DNA-binding function was added to the designed finger by reconsidering a section of the amino acid sequence and computationally selecting amino acids to have the lowest protein-DNA interaction energy for the target DNA sequences. Among the designed proteins, one had a gap between the lowest and second lowest protein-DNA interaction energies that was sufficient to give DNA sequence-specificity. 相似文献
93.
94.
Taichi Oguchi Yuko Kashimura Makiko Mimura Xiang Yu Etsuko Matsunaga Kazuya Nanto Teruhisa Shimada Akira Kikuchi Kazuo N. Watanabe 《Transgenic research》2014,23(5):767-777
A 4-year field trial for the salt tolerant Eucalyptus globulus Labill. harboring the choline oxidase (codA) gene derived from the halobacterium Arthrobacter globiformis was conducted to assess the impact of transgenic versus non-transgenic trees on biomass production, the adjacent soil microbial communities and vegetation by monitoring growth parameters, seasonal changes in soil microbes and the allelopathic activity of leaves. Three independently-derived lines of transgenic E. globulus were compared with three independent non-transgenic lines including two elite clones. No significant differences in biomass production were detected between transgenic lines and non-transgenic controls derived from same seed bulk, while differences were seen compared to two elite clones. Significant differences in the number of soil microbes present were also detected at different sampling times but not between transgenic and non-transgenic lines. The allelopathic activity of leaves from both transgenic and non-transgenic lines also varied significantly with sampling time, but the allelopathic activity of leaves from transgenic lines did not differ significantly from those from non-transgenic lines. These results indicate that, for the observed variables, the impact on the environment of codA-transgenic E. globulus did not differ significantly from that of the non-transformed controls on this field trial. 相似文献
95.
96.
Kazuya Hayashi Danji Fukushima Koya Mogi 《Bioscience, biotechnology, and biochemistry》2013,77(8):988-994
The molecular conformation of the alkaline proteinase of Aspergillus sojae in aqueous solution was investigated by the optical rotatory dispersion, Cotton effects, infra-red absorption spectra (amide I and V bands), ultraviolet difference spectra, etc. It is concluded that; (1) there are about 10 to 15% of the α-helix and a small amount of the β-structure in the enzyme molecule, but most parts of the peptide chain are present as the disordered structure; (2) the enzyme molecule is compactly folded even in the disordered parts; and (3) the two tryptophan residues involved in the peptide chain are burried in the interior of the molecule. 相似文献
97.
Hiroyuki Nishimura Akio Asahi Kazuya Fujiwara Junya Mizutani Yataro Obata 《Bioscience, biotechnology, and biochemistry》2013,77(12):1831-1835
The effect of γ-irradiation on the flavor of Onions (Senshu Yellow) associated with sprout-inhibition has been investigated. The relative amounts of propionaldehyde, n-propyl mercaptan and di-n-propyl disulfide in onions stored for 0, 5, 10, 20 and 30 days, respectively, after irradiation were estimated by measurement of peak areas of gas chromatograms. It was observed that the lachrymatory character and the pungent flavor had been decreased by γ-irradiation (remarkably at 70 and 700 Krads). In this connection, the amounts of propionaldehyde and di-n-propyl disulfide were decreased with increasing radiation dose and storage period at room temperature (20 to 25°C) and at low temperature (4°C). Moreover, it was observed that the sweetness had been decreased by γ-irradiation, but the amount of n-propyl mercaptan was increased with radiation dose and storage period. Therefore it seems that there is no correlation between the sweetness of onion and the amount of n-propyl mercaptan. 相似文献
98.
M-phase and S-phase protoplasts were prepared from tobacco cells in suspension culture after a high degree of synchronization using aphidicolin, a specific inhibitor for eukaryotic DNA polymerase. When TMV-RNA was introduced into these protoplasts mediated by REV liposomes, 37% of M-phase and 26% of S-phase protoplasts were infected as determined by the fluorescent antibody technique. After the 24 hr interval between the introduction of TMV-RNA into protoplasts and the determination of infection, half of the infected mitotic protoplasts formed dumbell-shaped daughter cells. The significance of synchronized protoplasts in genetic engineering of plant cells is discussed in reference to the delivery of DNA into the nucleus.Abbreviation LS
medium, Linsmaier and Skoog medium
- PEG
polyethylene glycol
- REV
reversephase evaporation vesicles
- TMV
tobacco mosaic virus 相似文献
99.
The effect of photosynthetically active radiation and temperature on the photosynthesis of two Vietnamese species of Sargassum,S. mcclurei and S. oligocystum,based on the field and laboratory measurements 下载免费PDF全文
Ryuta Terada Triet D. Vo Gregory N. Nishihara Kazuya Matsumoto Shogo Kokubu Yuki Watanabe Shigeo Kawaguchi 《Phycological Research》2016,64(4):230-240
SUMMARY The effects of photosynthetically active radiation (PAR) and temperature on the photosynthesis of two Vietnamese brown algae, Sargassum mcclurei and S. oligocystum (Fucales), were determined by field and laboratory measurements. Dissolved oxygen sensors and pulse‐amplitude modulated (PAM) fluorometry were used for the measurements of photosynthetic efficiency. A Diving‐PAM revealed that underwater measurements of the effective quantum yield (Φ PSII ) of both species declined with increasing incident PAR, with minimum Φ PSII occurring during noon to early afternoon. Φ PSII recovered in the evening, indicating photo‐adaptation to excessive PAR. In laboratory experiments, Φ PSII also decreased under continuous exposure to 1000 μmol photons m?2 s?1; and full recovery occurred after 12 h of dark acclimatization. The net photosynthesis – PAR experiments of S. mcclurei and S. oligocystum conducted at 28°C revealed that the net photosynthetic rate quickly increased at PAR below the saturation irradiance of 361 and 301 μmol photons m?2 s?1 and nearly saturated to maximum net photosynthetic rates of 385 and 292 μg O2 gww ? 1 min?1 without photoinhibition, respectively. Gross photosynthesis and dark respiration experiments determined over a range of temperatures (12–40°C), revealed that the maximum gross photosynthetic rates of 201 and 147 μg O2 gww ? 1 min?1 occurred at 32.9 and 30.7°C for S. mcclurei and S. oligocystum, respectively. The dark respiration rates increased exponentially over the temperature ranges examined. The estimated maximum value of the maximum quantum yield occurred at 19.3 and 20.0°C and was 0.76 and 0.74, respectively. Similar to the natural habitat of the study site, these two species tolerated the relatively high temperatures and broad range of PAR. The ability of these species to recover from exposure to high PAR is one of the mechanisms that allow them to flourish in the shallow water environment. 相似文献
100.
A bacterial consortium which rapidly mineralizes benzo[a]pyrene when it is grown on a high-boiling-point diesel fuel distillate (HBD) was recovered from soil and maintained for approximately 3 years. Previous studies have shown that mobilization of benzo[a]pyrene into the supernatant liquid precedes mineralization of this compound (R. Kanaly, R. Bartha, K. Watanabe, and S. Harayama, Appl. Environ. Microbiol. 66:4205-4211, 2000). In the present study, we found that sterilized supernatant liquid filtrate (SSLF) obtained from the growing consortium stimulated mineralization of benzo[a]pyrene when it was readministered to a consortium inoculum without HBD. Following this observation, eight bacterial strains were isolated from the consortium, and SSLF of each of them was assayed for the ability to stimulate benzo[a]pyrene mineralization by the original consortium. The SSLF obtained from one strain, designated BPC1, most vigorously stimulated benzo[a]pyrene mineralization by the original consortium; its effect was more than twofold greater than the effect of the SSLF obtained from the original consortium. A 16S rRNA gene sequence analysis and biochemical tests identified strain BPC1 as a member of the genus Rhodanobacter, whose type strain, Rhodanobacter lindaniclasticus RP5557, which was isolated for its ability to grow on the pesticide lindane, is not extant. Strain BPC1 could not grow on lindane, benzo[a]pyrene, simple hydrocarbons, and HBD in pure culture. In contrast, a competitive PCR assay indicated that strain BPC1 grew in the consortium fed only HBD and benzo[a]pyrene. This growth of BPC1 was concomitant with growth of the total bacterial consortium and preceded the initiation of benzo[a]pyrene mineralization. These results suggest that strain BPC1 has a specialized niche in the benzo[a]pyrene-mineralizing consortium; namely, it grows on metabolites produced by fellow members and contributes to benzo[a]pyrene mineralization by increasing the bioavailability of this compound. 相似文献