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101.
H. Akita Taeko Miyagi Keiko Hata Manabu Kagayama 《Histochemistry and cell biology》1997,107(6):495-503
Histochemical evidence is required to demonstrate the presence of biochemically defined cytosolic sialidase. To meet this
requirement, we examined the immunohistochemical localization of the enzyme in rat skeletal muscles. Sections of chemically
fixed tissues were incubated with a polyclonal antibody raised against a synthetic peptide which corresponded to a part of
the enzyme protein. After incubation with the primary antibody, cryosections for fluorescence microscopy and resin sections
for electron microscopy were incubated with a fluorochrome- and colloidal gold-labeled secondary antibody, respectively. Immunofluorescence
was diffusely distributed in the muscle fibers and was also found in the perimysium and blood vessels. Many immunogold particles
were scattered over the sarcoplasm, myofibrils, nucleoplasm, and matrix of mitochondria. The immunogold particles were also
found in the equivalent compartments of axons, Schwann cells, and cells of endomysium and blood vessels. The specificity of
the primary antibody was elucidated by immunoblotting and an immunoprecipitation test. These findings clearly indicate that
this type of sialidase is essentially located in the cytosolic compartment. Consequently, the name, cytosolic sialidase, will
be appropriate for this enzyme. Additionally it is indicated that this enzyme is also present in cells other than skeletal
muscle fibers.
Accepted: 29 January 1997 相似文献
102.
A Nicotiana tabacum cell line, KS-1, which is tolerant to morethan 1% NaCl, was treated with buthiobate. The cells accumulated14a-methylsterols such as obtusifoliol, instead of campesteroland sitosterol. The buthiobate-treated cells lost their salttolerance. These results suggest that the buthiobate-inducedsalt sensitivity is closely associated with changes in the molecularspecies of sterols in the cell membranes. (Received October 16, 1986; Accepted April 13, 1987) 相似文献
103.
The polymeric cobalt(II) porphyrin complexes were prepared from cobalt(II) protoporphyrin IX dimethyl ester(Co(II)P) and copolymers of 4-vinylpyridine and styrene(PSP), and their binding ability of molecular oxygen was studied in toluene solution. The five- and six-coordinate structure of CoP-PSP complexes were confirmed by esr spectra. The esr parameters for the CoP-PSP complexes were not affected by the molecular weight and the vinylpyridine-unit content of PSP-ligand. The 1:1 dioxygen-Co complex was reversibly formed when the solution of CoP-PSP was exposed to oxygen atmosphere at low temperature. While the visible spectra and esr parameters for the dioxygen complexes of CoP-PSP were the same as those of the CoP-pyridine complex, the equilibrium constant for the oxygen binding increased with the vinylpyridine-unit content of the PSP-ligand. The larger entropy change was observed for the oxygenation in the CoP-PSP system especially, of which the vinylpyridine-unit content was large. 相似文献
104.
The d(G4) and d(C4) molecules in the single stranded state were synthesized by the phosphotriester method and purified. The full duplex of tetramer d(G4).d(C4) was prepared by expending about a month. The duplex-to-single strand transition was observed by UV-spectroscopy. A standard hypochromic effect was observed, which is different from some experimental results reported previously. 相似文献
105.
K Hata R Kono M Fujisawa R Kitahara Y O Kamatari K Akasaka Y Xu 《Cellular and molecular biology, including cyto-enzymology》2004,50(4):311-316
We have investigated the effect of pressure and temperature on the structural and thermodynamic stability of a protein dihydrofolate reductase from a deep-sea bacterium Moritella profunda in its folate-bound form in the pressure range between 3 and 375 MPa and the temperature range between -5 and 30 degrees C. The on-line cell variable pressure 1H NMR spectroscopy has been used to analyze the chemical shift and signal intensity in one-dimensional 1H NMR spectra. Thermodynamic analysis based on signal intensities from protons in the core part indicates that the thermodynamic stability of Moritella profunda DHFR is relatively low over the temperature range between -5 and 30 degrees C (deltaG0=15.8 +/- 4.1 kJ/mol at 15 degrees C), but is well adapted to the living environment of the bacterium (2 degrees C and 28 MPa), with the maximum stability around 5 degrees C (at 0.1 MPa) and a relatively small volume change upon unfolding (deltaV= 66 +/- 19 ml/mol). Despite the relatively low overall stability, the conformation in the core part of the folded protein remains intact up to approximately 200 MPa, showing marked stability of the core of this protein. 相似文献
106.
Prevalence and Characteristics of eae-Positive Escherichia coli from Healthy Cattle in Japan 下载免费PDF全文
Hideki Kobayashi Akihiko Miura Hiroko Hayashi Torata Ogawa Takayuki End Eiji Hata Masashi Eguchi Ksi Yamamoto 《Applied microbiology》2003,69(9):5690-5692
The prevalence of eae-positive Escherichia coli (eaeEC) in Japan was examined using rectal stool samples taken from 35 calves less than 1 month old, 107 calves more than 1 to 3 months old, 88 heifers more than 3 to 6 months old, 214 heifers over 6 months old, and cows from 95 farms. Screening with eae PCR revealed the prevalence to be, with increasing age, 31.4, 8.4, 26.1, and 14.5%, respectively. Of 51 selected eaeEC strains, more than 40% were serotyped as O26, O103, O111, O145, or O157, which are frequently detected as enterohemorrhagic E. coli types. Four strains were identified as recently reported intimin types η, ι, and κ. 相似文献
107.
Mori Toyoki Takeuchi Tadayoshi Ohura Makoto Miyakoda Goro Fujiki Hiroyuki Orito Kensuke Yoshida Kenji Hirano Takahiro Yamamura Yoshitaka Sumida Takumi Nakaya Yutaka Satake Hiromu Hata Fumiaki 《Molecular and cellular biochemistry》1998,178(1-2):335-343
Pranidipine, a new calcium channel modulator, prolonged endothelium-dependent relaxation induced by acetylcholine in a aortic ring preparation, contracted with prostaglandin F2. This action was not shared by amlodipine. The effect was not modified by indomethacin, suggesting that the action of pranidipine does not involve prostanoid metabolism. NG-nitro-L-arginine completely prevented the action of Pranidipine. The drug affected neither nitric oxide (NO) synthase activity nor the level of cyclic GMP in the vessel. Pranidipine did not affect the sensitivity of the contractile proteins to calcium. Pranidipine also did not alter cyclic GMP-induced relaxation in a-toxinskinned vascular preparations. Pranidipine also prolonged glyceryl trinitrate-induced relaxation in the endothelium denuded rat aorta. Furthermore, pranidipine enhanced relaxation of the aorta induced by glyceryl trinitrate even in the presence of methylene blue, a guanylyl cyclase inhibitor. This action was not modified by iberiotoxin or by charybdotoxin, two inhibitors of the calciumactivated potassium channel. The results strongly suggest that pranidipine enhances cyclic GMPindependent NO-induced relaxation of smooth muscle by a mechanism other than through NOinduced hyperpolarization. These effects were in direct contrast to amlodipine, another new 1,4dihydropyridine calcium antagonist. 相似文献
108.
109.
110.
Phylogenetics of family Enterobacteriaceae and proposal to reclassify Escherichia hermannii and Salmonella subterranea as Atlantibacter hermannii and Atlantibacter subterranea gen. nov., comb. nov. 下载免费PDF全文
Hiroyuki Hata Tatsuya Natori Takuya Mizuno Izumi Kanazawa Ibrahim Eldesouky Masahiro Hayashi Machiko Miyata Hajime Fukunaga Shoko Ohji Akira Hosoyama Eiji Aono Atsushi Yamazoe Keiko Tsuchikane Nobuyuki Fujita Takayuki Ezaki 《Microbiology and immunology》2016,60(5):303-311
Multilocus sequence analysis based on hypervariable housekeeping proteins was utilized to differentiate closely related species in the family Enterobacteriaceae. Of 150 housekeeping proteins, the top 10 hypervariable proteins were selected and concatenated to obtain distance data. Distances between concatenated proteins within the family were 0.9–41.2%, whereas the 16S rRNA and atpD‐gyrB‐infB‐rpoB concatenated sequence (4MLSA) distances were 0.8–6.0% and 0.9–22.1%, respectively. These data indicate that phylogenetic analysis by concatenation of hypervariable proteins is a powerful tool for discriminating species in the family Enterobacteriaceae. To confirm the discriminatory power of the 10 chosen concatenated hypervariable proteins (C10HKP), phylogenetic trees based on C10HKP, 4MLSA, and the 16S rRNA gene were constructed. Comparison of average bootstrap values among C10HKP, 4MLSA and 16S rRNA genes indicated that the C10HKP tree was the most reliable. Location via the C10HKP tree was consistent with existing assignments for almost all species in the family Enterobacteriaceae. However, the C10HKP tree suggested that several species (including Enterobacter massiliensis, Escherichia vulneris, Escherichia hermannii, and Salmonella subterranea) should be reassigned to different clusters than those defined in previous analyses. Furthermore, E. hermannii and S. subterranea appeared to fall onto a branch independent from those occupied by the other Enterobacteriaceae. Therefore, we propose Atlantibacter gen. nov., such that E. hermannii and S. subterranea would be transferred to genus Atlantibacter as Atlantibacter hermannii, comb. nov. and Atlantibacter subterranea. comb. nov., respectively. 相似文献