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1.
H Munakata K Satoh M Kosakai J Aikawa M Isemura Z Yosizawa N Hayashi M Motomiya 《The International journal of biochemistry》1987,19(6):503-507
A high molecular weight glycoprotein was isolated from the lavage fluid of a patient with alveolar proteinosis by gel chromatography with Sepharose CL-4B. The glycoprotein gave a single band stainable with alcian blue and with periodate-Schiff reagent on the cellulose acetate membrane electrophoresis. The glycoprotein did not penetrate 3.3% polyacrylamide gel but moved into 1% agarose gel as a periodate-Schiff positive single band, when electrophoresed in the presence of sodium dodecyl sulfate. The chemical analysis and the results of the beta-elimination reaction showed the presence of O-linked carbohydrate chains characteristic for a mucin-type glycoprotein. These data provide the first characterization of a mucin-type glycoprotein isolated from lung in pulmonary alveolar proteinosis. 相似文献
2.
Transport of an Mr approximately 300,000 Plasmodium falciparum protein (Pf EMP 2) from the intraerythrocytic asexual parasite to the cytoplasmic face of the host cell membrane 总被引:6,自引:3,他引:3 下载免费PDF全文
R J Howard J A Lyon S Uni A J Saul S B Aley F Klotz L J Panton J A Sherwood K Marsh M Aikawa 《The Journal of cell biology》1987,104(5):1269-1280
The profound changes in the morphology, antigenicity, and functional properties of the host erythrocyte membrane induced by intraerythrocytic parasites of the human malaria Plasmodium falciparum are poorly understood at the molecular level. We have used mouse mAbs to identify a very large malarial protein (Mr approximately 300,000) that is exported from the parasite and deposited on the cytoplasmic face of the erythrocyte membrane. This protein is denoted P. falciparum erythrocyte membrane protein 2 (Pf EMP 2). The mAbs did not react with the surface of intact infected erythrocytes, nor was Pf EMP 2 accessible to exogenous proteases or lactoperoxidase-catalyzed radioiodination of intact cells. The mAbs also had no effect on in vitro cytoadherence of infected cells to the C32 amelanotic melanoma cell line. These properties distinguish Pf EMP 2 from Pf EMP 1, the cell surface malarial protein of similar size that is associated with the cytoadherent property of P. falciparum-infected erythrocytes. The mAbs did not react with Pf EMP 1. In one strain of parasite there was a significant difference in relative mobility of the 125I-surface-labeled Pf EMP 1 and the biosynthetically labeled Pf EMP 2, further distinguishing these proteins. By cryo-thin-section immunoelectron microscopy we identified organelles involved in the transit of Pf EMP through the erythrocyte cytoplasm to the internal face of the erythrocyte membrane where the protein is associated with electron-dense material under knobs. These results show that the intraerythrocytic malaria parasite has evolved a novel system for transporting malarial proteins beyond its own plasma membrane, through a vacuolar membrane and the host erythrocyte cytoplasm to the erythrocyte membrane, where they become membrane bound and presumably alter the properties of this membrane to the parasite's advantage. 相似文献
3.
4.
Takashi Yutsudo Hisao Kurazono Chihiro Sasakawa Masanosuke Yoshikawa Makoto Iwaya Tae Takeda Yoshifumi Takeda 《FEMS microbiology letters》1987,48(1-2):273-276
Abstract A Vero toxin (VT2 or Shiga-like toxin II)-converting phage was isolated from Escherichia coli 0157: H7 strain J-2. Nontoxigenic E. coli C600 produced VT2 when lysogenized with the toxin-converting phage. Eco RI fragments of the phage DNA were ligated with Eco RI-digested pBR322 or pUC118 and were transformed into E. coli MC1061 or MV1184. Transformants exhibiting VT2 production commonly contained a 4.6 kb Eco RI fragment. It was found that a 2.3 kb Kpn I- Sph I fragment coded VT2 production and that this fragment hybridized weakly with the 2.1 kb fragment encoding VT1. 相似文献
5.
Junzou Hiratsuka Hiroaki Shimada Robert Whittier Takashi Ishibashi Masahiro Sakamoto Masao Mori Chihiro Kondo Yasuko Honji Chong-Rong Sun Bing-Yuan Meng Yu-Qing Li Akira Kanno Yoko Nishizawa Atsushi Hirai Kazuo Shinozaki Masahiro Sugiura 《Molecular & general genetics : MGG》1989,217(2-3):185-194
Summary The entire chloroplast genome of the monocot rice (Oryza sativa) has been sequenced and comprises 134525 bp. Predicted genes have been identified along with open reading frames (ORFs) conserved
between rice and the previously sequenced chloroplast genomes, a dicot, tobacco (Nicotiana tabacum), and a liverwort (Marchantia polymorpha). The same complement of 30 tRNA and 4 rRNA genes has been conserved between rice and tobacco. Most ORFs extensively conserved
betweenN. tabacum andM. polymorpha are also conserved intact in rice. However, several such ORFs are entirely absent in rice, or present only in severely truncated
form. Structural changes are also apparent in the genome relative to tobacco. The inverted repeats, characteristic of chloroplast
genome structure, have expanded outward to include several genes present only once per genome in tobacco and liverwort and
the large single copy region has undergone a series of inversions which predate the divergence of the cereals. A chimeric
tRNA pseudogene overlaps an apparent endpoint of the largest inversion, and a model invoking illegitimate recombination between
tRNA genes is proposed which accounts simultaneously for the origin of this pseudogene, the large inversion and the creation
of repeated sequences near the inversion endpoints. 相似文献
6.
Ultrastructure of malaria-infected erythrocytes 总被引:7,自引:0,他引:7
Knobs, caveolae, caveola-vesicle complexes, cytoplasmic clefts, and electron-dense material are five major ultrastructural changes found in the membrane skeleton and cytoplasm of erythrocytes infected with species of primate malaria. Knobs are electron-dense, conical evaginations of the erythrocyte surface, which are believed to mediate cytoadherence and sequestration of Plasmodium falciparum-infected erythrocytes. Caveolae and caveola-vesicle complexes are flask-shaped invaginations of the membrane skeleton, which may be involved in the uptake or export of host- or parasite-derived substances. Cytoplasmic clefts are flattened or circular membranous structures found in the erythrocyte cytoplasm between the intracellular parasite and the host cell surface. The clefts are variable in length and bounded by two or more membranes. Fine, granular electron-dense material is often found on the cytoplasmic face of clefts or in amorphous packets in the erythrocyte cytoplasm. Immunocytochemistry has demonstrated that all of these ultrastructural changes are associated with the trafficking and interaction of specific malarial antigens with the host erythrocyte. 相似文献
7.
Antimutagenic effect of volatile decomposition products from thermally oxidized linoleate 总被引:1,自引:0,他引:1
The antimutagenic effect of volatile decomposition products from thermally oxidized linoleate on mutagenesis by UV irradiation was investigated in Escherichia coli B/r WP2. When added to an agar medium, these products greatly reduced the number of Trp+ revertants. The same antimutagenic effect was observed by acrolein, 2-hexenal, 2-heptenal, 2-nonenal and 2,4-decadienal; these unsaturated aldehydes were components of volatile products. 相似文献
8.
Dr. Tomonobu Kusano Kazuyuki Sugawara Chihiro Inoue Nobuhiro Suzuki 《Current microbiology》1991,22(1):35-41
The genes coding ford-ribulose-1,5-bisphosphate carboxylase (RuBPCase) from an iron-oxidizing bacterium,Thiobacillus ferrooxidans, were cloned into anEscherichia coli plasmid, pUC18. The recombinant plasmid, termed pTR11, contained a 4.0-kb PstI fragment including the entire coding regions for both large and small subunits of RuBPCase.Escherichia coli carrying pTR11 did not show any CO2-fixing activity. However, a derivative plasmid with an appropriate deletion, which was placed under the control of atac promoter, conferred ribulose bisphosphate-dependent CO2-fixing activity on the host cell. Analysis of gel-filtration chromatography of the RuBPCase synthesized inE. coli revealed that it had a hexadecameric form like the native enzyme ofT. ferrooxidans. 相似文献
9.
Plasmodium gallinaceum: critical role for microtubules in the transformation of zygotes into Ookinetes 总被引:1,自引:0,他引:1
The role of microtubules and microfilaments in the transformation of spherical zygotes of Plasmodium gallinaceum (avian malaria parasite) into vermiform ookinetes has been studied by using specific drugs (taxol, colchicine, and cytochalasin-B). Both taxol and colchicine completely abolished the transformation of zygotes into ookinetes. The inhibitory effect was seen only if the drugs were added during the initial 6 hr of total time (20-24 hr) required for complete transformation; the addition of drugs after 6-8 hr of initiation of transformation had no effect. Electron microscopy revealed that microtubules were depolymerized by colchicine treatment, whereas in taxol-treated cells there was an extensive array of cytoplasmic and nuclear microtubules which appeared to be clumped in bundles. In contrast to the effects of taxol and colchicine, cytochalasin-B, which affects the microfilament system, had no effect on the transformation. Protein synthesis and expression of two ookinete-specific surface proteins were not affected in the drug-inhibited parasites. Zygotes treated with taxol for 4 hr at room temperature failed to develop into oocysts when they were subsequently fed to mosquitoes. These studies demonstrate a critical role for microtubules in the initial stages of transformation of zygotes into ookinetes. 相似文献
10.
Isolation and characterization of human placenta fibronectin 总被引:3,自引:0,他引:3
M Isemura Y Yamaguchi H Munakata J Aikawa M Kan I Yamane Z Yosizawa 《Journal of biochemistry》1984,96(1):163-169
Fibronectin was isolated from human placenta tissues and compared with human plasma fibronectin. Placenta and plasma fibronectins had similar amino acid compositions, immunological properties, and cell attachment-promoting activities, but differed in apparent molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which could be accounted for at least partly by the difference in carbohydrate composition. Unlike plasma fibronectin, placenta fibronectin failed to form a precipitin line with concanavalin A in a double diffusion system. The non- or low-reactivity of placenta fibronectin with this lectin was also demonstrated by affinity chromatography with concanavalin A-agarose, in which more than 90% of the radiolabeled glycopeptides derived from placenta fibronectin was not retained on the gel. The two fibronectins also differed in the reactivity with Lens culinaris agglutinin of their glycopeptide fractions. These data indicate that placenta and plasma fibronectins are different in their carbohydrate structures and, therefore, suggest the presence of a tissue- or cell-specific mechanism for processing the carbohydrates of this glycoprotein. 相似文献