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21.
Hiide Yoshino Nobuyuki Miyatani Megumi Saito Toshio Ariga Alessandra Lugaresi Norman Latov Yasunori Kushi Takeshi Kasama Robert K. Yu 《Journal of neurochemistry》1992,59(5):1684-1691
The gangliosides GM1 and GD1b have recently been reported to be potential target antigens in human motor neuron disease (MND) or motor neuropathy. The mechanism for selective motoneuron and motor nerve impairment by the antibodies directed against these gangliosides, however, is not fully understood. We recently investigated the ganglioside composition of isolated bovine spinal motoneurons and found that the ganglioside pattern of the isolated motoneurons was extremely complex. GM1, GD1a, GD1b, and GT1b, which are major ganglioside components of CNS tissues, were only minor species in motoneurons. Among the various ganglioside species in motoneurons, several were immunoreactive to sera from patients with MND and motor neuropathy. One of these gangliosides was purified from bovine spinal cord and characterized as N-glycolylneuraminic acid-containing GM1 [GM1(NeuGc)] by compositional analysis, fast atom bombardment mass spectra, and the use of specific antibodies. Among seven sera with anti-GM1 antibody activities, five sera reacted with GM1(NeuGc) and two did not. Two other gangliosides, which were recognized by another patient's serum, appeared to be specific for motoneurons. We conclude that motoneurons contained, in addition to the known ganglioside antigens GM1 and GD1b, other specific ganglioside antigens that could be recognized by sera from patients with MND and motor neuropathy. 相似文献
22.
Y Nakahashi S Taketani M Okuda K Inoue R Tokunaga 《Biochemical and biophysical research communications》1990,173(2):748-755
The cDNA encoding human ferrochelatase [EC 4.99.1.1] was isolated from a human placenta cDNA library in bacteriophage lambda gt11 by screening with a radiolabeled fragment of mouse ferrochelatase cDNA. The cDNA had an open reading frame of 1269 base pairs (bp) encoding a protein of 423 amino acid residues (Mr. 47,833) with alternative putative polyadenylation signals in the 3' non-coding regions and poly (A) tails. Amino acid sequencing showed that the mature protein consists of 369 amino acid residues (Mr. 42,158) with a putative leader sequence of 54 amino acid residues. The human enzyme showed an 88% identity to mouse enzyme and 46% to yeast enzyme. Northern blot analysis showed two mRNAs of about 2500 and 1600 bp for ferrochelatase in K562 and HepG2 cells. As full-length cDNA for human ferrochelatase is now available, molecular lesions related to erythropoietic protoporphyria can be characterized. 相似文献
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A homgenate of Saccharomyces cerevisiae grown under semi-anaerobic as well as aerobic conditions was found to catalyze the hydrolysis of fatty acid esters of sterols in the presence of Triton X-100. The enzyme levels in cells grown under various conditions were similar and the enzyme had a broad substrate specificity for sterol esters. The enzyme was localized in the mitochondrial fraction for the aerobically grown cells and in the mitochondrial and cytosolic fractions for the semi-anaerobically grown cells. 相似文献
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Hyperimmune and high-titered polyclonal pneumococcal antisera, specific for cross-reactive types within groups, were produced in adult rabbits. Purified capsular polysaccharide was injected intravenously into adult rabbits. One week later, these rabbits were given multiple intravenous injections of formalin-inactivated pneumococci of the cross-reactive type by an established method. Each of the resultant antisera were specific for the cross-reactive type indicating that the previous injection of the polysaccharide had induced epitope-specific tolerance. This method was successful for production of antisera against pneumococcal types 6A, 6B, 9N, 9V, 19F and 19A. Polyclonal rabbit pneumococcal antisera have some advantages over murine monoclonal antibodies for serologic studies and this method should be applicable for producing type-specific antibodies to cross-reactive polysaccharides of clinical interest. Further, this method is simpler and generally produces higher titered monovalent (factor) reagents than absorbed antisera. 相似文献
25.
Natsuki Osaka Yu kanesaki Megumi Watanabe Satoru Watanabe Taku Chibazakura Hiraku Takada Hirofumi Yoshikawa Kei Asai 《Molecular microbiology》2020,113(6):1155-1169
In bacteria, guanosine (penta)tetra-phosphate ([p]ppGpp) is essential for controlling intracellular metabolism that is needed to adapt to environmental changes, such as amino acid starvation. The (p)ppGpp0 strain of Bacillus subtilis, which lacks (p)ppGpp synthetase, is unable to form colonies on minimal medium. Here, we found suppressor mutations in the (p)ppGpp0 strain, in the purine nucleotide biosynthesis genes, prs, purF and rpoB/C, which encode RNA polymerase core enzymes. In comparing our work with prior studies of ppGpp0 suppressors, we discovered that methionine addition masks the suppression on minimal medium, especially of rpoB/C mutations. Furthermore, methionine addition increases intracellular GTP in rpoB suppressor and this effect is decreased by inhibiting GTP biosynthesis, indicating that methionine addition activated GTP biosynthesis and inhibited growth under amino acid starvation conditions in (p)ppGpp0 backgrounds. Furthermore, we propose that the increase in intracellular GTP levels induced by methionine is due to methionine derivatives that increase the activity of the de novo GTP biosynthesis enzyme, GuaB. Our study sheds light on the potential relationship between GTP homeostasis and methionine metabolism, which may be the key to adapting to environmental changes. 相似文献
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Kenta Shirasawa Kohei Ishii Cholgwang Kim Tomohiro Ban Munenori Suzuki Takashi Ito Toshiya Muranaka Megumi Kobayashi Noriko Nagata Sachiko Isobe Satoshi Tabata 《Molecular breeding : new strategies in plant improvement》2013,31(1):101-110
Capsicum spp. are widely cultivated for use as vegetables and spices. The Kihara Institute for Biological Research, Yokohama City University, Japan, has stocks of approximately 800 lines of Capsicum spp. collected from various regions of Central and South America, the regions of origin for Capsicum spp. In this study, 5,751 primer pairs for simple sequence repeat markers, based on 118,060 publicly available sequences of expressed sequence tags of Capsicum annuum, were designed and subjected to a similarity search against the genomic sequence of tomato, a model Solanaceae species. Nucleotide sequences spanning 2,245 C. annuum markers were successfully mapped onto the tomato genome, and 96 of these, which spanned the entire tomato genome, were selected for further analysis. In genotyping analysis, 60 out of the 77 markers that produced specific DNA amplicons showed polymorphism among the Capsicum lines examined. On the basis of the resulting data, the 192 tested lines were grouped into five main clusters. The additional sequencing analysis of the plastid genes, matK and rbcL, divided the resources into three groups. As a result, 19 marker loci exhibited genotypes specific to species and cluster, suggesting that the DNA markers are useful for species identification. Information on the DNA markers will contribute to Capsicum genetics, genomics, and breeding. 相似文献
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Muichi Kaito Shin-Ichi Araya Yuichiro Gondo Michiyo Fujita Naomi Minato Megumi Nakanishi Makoto Matsui 《PloS one》2013,8(8)