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11.
The major glycoproteins of horse and swine erythrocyte membranes were isolated and examined chemically and immunologically. The major glycoprotein of horse erythrocyte membranes had a molecular weight of 33 000 and consisted of 46.2% protein and 53.8% carbohydrate, of which 9.4% was hexose, 10.1% hexosamine and 33.7% sialic acid. This glycoprotein was associated with activity for the infectious mononucleosis heterophile antigen.There were two different major glycoproteins in swine erythrocyte membranes. One major glycoprotein had a molecular weight of 46 200 and consisted of 34.2% protein and 65.8% carbohydrate, of which 18% was hexose, 19% hexosamine and 27.2% sialic acid. This glycoprotein had phytohemagglutinin (Phaseolus vulgaris) binding activity. The other glycoprotein had a molecular weight of 29 000 and consisted of 50.4% protein and 49.6% carbohydrate, of which 6.4% was hexose, 7.0% hexosamine and 36.3% sialic acid. This glycoprotein had weak or absent phytohemagglutinin binding activity. 相似文献
12.
Electron microscopic examination showed microtubular structures in FL cells infected with all 18 strains of HSV-2 examined, but not in cells infected with 9 strains of HSV-1. These structures were also detected in other cultured cells (Vero and Earle's L cells) infected with HSV-2, and also in vivo in cells, such as neuronal cells of the spinal ganglia and liver cells, of one-day-old suckling mice (DDD strain) infected with this type of virus. Thus the microtubules were consistently detected in cells productively infected with HSV-2. No other herpesviruses so far examined produced microtubular structures such as those observed in HSV-2 infected cells. 相似文献
13.
Xiaoling Tong Hiroshi Aoyama Swathy Sudhakar Honghong Chen Brian H. Shilton Donglin Bai 《PloS one》2015,10(12)
Gap junction (GJ) channels provide direct passage for ions and small molecules to be exchanged between neighbouring cells and are crucial for many physiological processes. GJ channels can be gated by transjunctional voltage (known as Vj-gating) and display a wide range of unitary channel conductance (γj), yet the domains responsible for Vj-gating and γj are not fully clear. The first extracellular domain (E1) of several connexins has been shown to line part of their GJ channel pore and play important roles in Vj-gating properties and/or ion permeation selectivity. To test roles of the E1 of Cx50 GJ channels, we generated a chimera, Cx50Cx36E1, where the E1 domain of Cx50 was replaced with that of Cx36, a connexin showing quite distinct Vj-gating and γj from those of Cx50. Detailed characterizations of the chimera and three point mutants in E1 revealed that, although the E1 domain is important in determining γj, the E1 domain of Cx36 is able to effectively function within the context of the Cx50 channel with minor changes in Vj-gating properties, indicating that sequence differences between the E1 domains in Cx36 and Cx50 cannot account for their drastic differences in Vj-gating and γj. Our homology models of the chimera and the E1 mutants revealed that electrostatic properties of the pore-lining residues and their contribution to the electric field in the pore are important factors for the rate of ion permeation of Cx50 and possibly other GJ channels. 相似文献
14.
Takaki Hiwasa Jun Ma Yoshimasa Ike Nobuhiko Katunuma Shigeru Sakiyama 《Cell biochemistry and function》1995,13(4):293-296
Degradation of cyclin B was effectively suppressed when cells were treated with ALLN (N-acetylleucylleucylnorleucinal) which inhibits proteasome, calpain and cysteine proteinase cathepsins. In order to examine which protease degrades cyclin B, the effect of a cathepsin inhibitor, cystatin α, was investigated. The cystatin α gene was inserted into an inducible expression vector, pMSG, and transfected into NIH3T3 mouse fibroblasts. The expression of cystatin α was induced effectively in the transfected cells after treatment with dexamethasone. Overexpression of cystatin α resulted in an increase of the amount of cyclin B, suggesting that cysteine proteinase cathepsins might be involved in the degradation of cyclin B. 相似文献
15.
Abstract Eighteen strains of Rhizobium including four species, R. leguminosarum, R. meliloti, R. loti and R. fredii , nine strains of Bradyrhizobium japonicum and three strains of Azorhizobium caulinodans contained putrescine and honospermidine as major polyamines. All these nodulating N2 -fixing rhizobia lack spermidine. Spermidine and cadaverine were present only in a limited number of R. meliloti and B. japonicum . Polymanine-synthetic activity was not affected by the differences in ability to produce phytoxine (rhizobitoxine and dihydrorhizobitoxine) H2 -uptake-hydrogenation in the organisms. Putrescine and homospermidine were major polyamined in a strain of Agrobacterium rhizogenes . All the eight strains of Agrobacterium tumefaciens as well as A. rubi, A. radiobacter and two other strains of A. rhizogenes contained putrescine and spermidine as major polyamines and homospermidine and spermine (and thermospermine) as minor polyamines. 相似文献
16.
Akitoshi Nakashima Mikiko Yamanaka-Tatematsu Naonobu Fujita Keiichi Koizumi Tomoko Shima Toshiko Yoshida Toshio Nikaido Aikou Okamoto Tamotsu Yoshimori Shigeru Saito 《Autophagy》2013,9(3):303-316
In early pregnancy, trophoblasts and the fetus experience hypoxic and low-nutrient conditions; nevertheless, trophoblasts invade the uterine myometrium up to one third of its depth and migrate along the lumina of spiral arterioles, replacing the maternal endothelial lining. Here, we showed that autophagy, an intracellular bulk degradation system, occurred in extravillous trophoblast (EVT) cells under hypoxia in vitro and in vivo. An enhancement of autophagy was observed in EVTs in early placental tissues, which suffer from physiological hypoxia. The invasion and vascular remodeling under hypoxia were significantly reduced in autophagy-deficient EVT cells compared with wild-type EVT cells. Interestingly, soluble endoglin (sENG), which increased in sera in preeclamptic cases, suppressed EVT invasion by inhibiting autophagy. The sENG-inhibited EVT invasion was recovered by TGFB1 treatment in a dose-dependent manner. A high dose of sENG inhibited the vascular construction by EVT cells and human umbilical vein endothelial cells (HUVECs), meanwhile a low dose of sENG inhibited the replacement of HUVECs by EVT cells. A protein selectively degraded by autophagy, SQSTM1, accumulated in EVT cells in preeclamptic placental biopsy samples showing impaired autophagy. This is the first report showing that impaired autophagy in EVT contributes to the pathophysiology of preeclampsia. 相似文献
17.
Takashi Saitoh Jon Olav Vik Nils Chr. Stenseth Toshikazu Takanishi Shintaro Hayakashi Nobuo Ishida Masaaki Ohmori Toshio Morita Shigeru Uemura Masahiko Kadomatsu Jun Osawa Koji Maekawa 《Population Ecology》2008,50(2):159-167
We analysed the effects of Quercus crispula acorn abundance on the density dependence of the large Japanese wood mouse Apodemus speciosus using time series data (1992–2007). The data were obtained in a forest in northern Hokkaido, Japan, by live-trapping rodents
and directly counting acorns on the ground. Acorn abundance in one year clearly influenced the abundance of wood mice in the
following year in all models examined based on the Gompertz and Ricker model; in addition, the abundance of wood mice had
effects on the population. Acorn abundance influenced the strength of density dependence (intraspecific competition) of the
wood mouse population. When the abundance of acorns was high, density dependence was relaxed, and as a result the equilibrium
density at which the population growth rate decreased to zero became higher. Those effects of acorn abundance were regarded
as a nonlinear perturbation effect (sensu Royama 1992). The nonlinearity of density dependence was also detected; higher densities had stronger effects on population growth rates.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
18.
Noriharu Umetsu Jun Kaji Keiko Aoyama Kinjiro Tamari 《Bioscience, biotechnology, and biochemistry》2013,77(10):1867-1874
The occurence of tenuazonic acid (T.A.), which had been isolated from the culture broth of blast fungus, in blast-diseased rice plants was surveyed to ascertain whether or not this substance is one of the vivotoxins. T.A. was detected in four of six samples of blast-diseased rice plants, two of which had relatively high T.A. contents; 379 and 91 mg per kg of the samples (dry weight).Besides T.A., coumarin, o-coumaric acid and piricularin were also isolated from blast-diseased rice plants. The molecular formula of the last substance, which was tentatively presented in a previous paper, was corrected to C18H30N2O5 from the results of high resolution mass spectrometry. 相似文献
19.
Takuro Nunoura Yoshihiro Takaki Hiromi Kazama Jungo Kakuta Shigeru Shimamura Hiroko Makita Miho Hirai Masayuki Miyazaki Ken Takai 《PloS one》2014,9(8)
Strain Hiromi 1, a sulfur-oxidizing gammaproteobacterium was isolated from a hydrothermal vent chimney in the Okinawa Trough and represents a novel genus that may include a phylogenetic group found as endosymbionts of deep-sea gastropods. The SSU rRNA gene sequence similarity between strain Hiromi 1 and the gastropod endosymbionts was approximately 97%. The strain was shown to grow both chemolithoautotrophically and chemolithoheterotrophically with an energy metabolism of sulfur oxidation and O2 or nitrate reduction. Under chemolithoheterotrophic growth conditions, the strain utilized organic acids and proteinaceous compounds as the carbon and/or nitrogen sources but not the energy source. Various sugars did not support growth as a sole carbon source. The observation of chemolithoheterotrophy in this strain is in line with metagenomic analyses of endosymbionts suggesting the occurrence of chemolithoheterotrophy in gammaproteobacterial symbionts. Chemolithoheterotrophy and the presence of homologous genes for virulence- and quorum sensing-related functions suggest that the sulfur-oxidizing chomolithotrophic microbes seek animal bodies and microbial biofilm formation to obtain supplemental organic carbons in hydrothermal ecosystems. 相似文献
20.