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991.
992.
Atsushi Saeki Nobuo Kido Tsuyoshi Sugiyama Michio Ohta Toshihide Iwashita Keiichi Uchiya Nobuo Kato 《Microbiology and immunology》1993,37(8):601-606
Four serotypes of two genera, Escherichia coli O8 and O9 and Klebsiella O3 and O5, produce the O polysaccharides consisting of mannose homopolymers. Previously we reported the isolation and expression of E. coli O9 rfb in E. coli K-12 strains (Kido et al, J. Bacteriol., 171: 3629–3633, 1989). In this study, R' plasmids carrying his-rfb region of the other three strains were isolated and expressed in E. coli K-12 strain. Serological study of lipopolysaccharides (LPS) synthesized in E. coli K-12 strain was carried out. His-linked rfb genes from E. coli O9 and Klebsiella O3 directed the synthesis of O polysaccharides with the same antigenicity as those of the parental strains in E. coli K-12 strain. On the other hand, rfb genes from E. coli O8 and Klebsiella O5 directed the synthesis of O polysaccharides which were antigenically not identical but partially common to those of the parental strains. A rough strain derived from E. coli O8 synthesized LPS which showed the identical antigenicity as the wild strain when the his-rfb region of E. coli O8 was introduced. The results suggest that some genes located distantly from his are additionally required to complete the synthesis of O polysaccharides of E. coli O8 and Klebsiella O5. 相似文献
993.
Botulinal neurotoxin in and around colonies of Clostridium botulinum types A, B, and E and of toxigenic Clostridium butyricum was detected by an enzyme-linked immunoassay procedure whereby the toxin was transferred from the agar medium to a nitrocellulose support and the immobilized toxin was probed with type-specific antibodies. The method identified the toxin types of the colonies grown from a mixed inoculum of C. botulinum serotypes. The specificity of the antitoxins for type A and B toxins was improved by adsorption of the antitoxins with the antigens of heterologous type cultures. 相似文献
994.
The nucleotide sequence of the small-subunit rRNA (18S rRNA) coding gene in the higher fungus Protomyces inouyei contains two group I introns. This is the first report of two group I introns in the 18S rRNA coding region. Based on the comparison of the two introns of Protomyces inouyei with those of the green alga Ankistrodesmus stipitatus, and the other two higher fungi Pneumocystis carinii and Ustilago maydis, the Protomyces introns are group I introns containing the highly conserved sequence elements P, Q, R, and S. Intron A of Protomyces inouyei is located in the same position as in Pneumocystis carinii while intron B shares the location with that in Ustilago maydis. The phylogenetic relationships strongly support horizontal transfer of these group I introns.Correspondence to: J. Sugiyama 相似文献
995.
Koki Yoshida 《Plant cell reports》1995,15(1-2):43-50
Summary Nojirimycin bisulfite andp-nitrophenyl-1-thio-ß-D-glucoside, potent inhibitors of ß-glucanase, suppressed cortical dissociation and callus growth in rice roots (Oryza sativa L. cv. Sasanishiki) in the presence of 2,4-D, with resultant suppression of the emergence of callus clumps from the interior of root tissues. These sugar analogs inhibited the 2,4-D-induced increase in the elastic and plastic compliance of cell walls but did not affect oxygen uptake by root explants in the presence of 2,4-D. They also inhibited the activities of CM-cellulase, ß-glucosidase and -arabinosidase in 2 M NaCl-soluble and/or buffer-soluble fractions of crude root extracts. Involvement of glycan hydrolase activities in cell wall dissociation during callus emergence is discussed.Abbreviations BS
buffer-soluble
- CM
carboxymethyl
- DTT
dithiothreitol
- NS
2 M NaCl-soluble
- PNP
p -nitrophenyl
- PNPT-glucoside
p -nitrophenyl-1-thio-ß-D-glucoside 相似文献
996.
Kazuyuki Sugiyama Hiroki Narita Takeshi Yamamoto Toshiya Senda Kazuhide Kimbara Norio Inokuchi Masanori Iwama Masachika Irie Masao Fukuda Keiji Yano Yukio Mitsui 《Proteins》1995,22(3):284-286
Crystals have been obtained for a 2,3-dihydroxybiphenyl dioxygenase (conventionally called BphC) from a polychlorinated biphenyl (PCB)-degrader, Pseudomonas sp. strain KKS1O2. The crystals were grown using both ammonium sulfate and MPD as the precipitating agents. The crystals belonged to a tetragonal space group (I422) and diffracted to 2.5 Å. © 1995 Wiley-Liss, Inc. 相似文献
997.
Hitoshi Osaka Ken Inoue Chiaki Kawanishi Yoshiteru Yamada Hideki Onishi Naoya Sugiyama Kyoko Suzuki Atsuo Nezu Seiji Kimura Kenji Kosaka 《Human genetics》1995,95(4):461-461
We report a rare polymorphism in the human proteolipid protein (PLP) gene. A synonymous mutation, 168 AG, was detected in exon 2 of the PLP gene. Mutations in this gene have been reported in some cases of Pelizaeus-Merzbacher disease. 相似文献
998.
Programming of cell death during xylogenesis 总被引:2,自引:0,他引:2
Hiroo Fukuda Yoriko Watanabe Hideo Kuriyama Shigemi Aoyagi Munetaka Sugiyama Ryo Yamamoto Taku Demura Atsushi Minami 《Journal of plant research》1998,111(2):253-256
Death of tracheary elements which compose vessels and tracheids is a typical example of programmed cell death in plants. Anin vitro system usingZinnia mesophyll cells which differentiate directly into tracheary elements has provided various types of data on the cell death
process. In this paper, we will summarize recent results obtained using theZinnia system and discuss the programming of cell death during tracheary element differentiation.
The extended abstract of a paper presented at the 13th International Symposium in Conjugation with Award of the International
Prize for Biology “Frontier of Plant Biology” 相似文献
999.
1000.
Complete Sequence and Gene Organization of the Genome of a Hyper-thermophilic Archaebacterium, Pyrococcus horikoshii OT3 总被引:13,自引:0,他引:13
Kawarabayasi Yutaka; Sawada Mituhiro; Horikawa Hiroshi; Haikawa Yuji; Hino Yumi; Yamamoto Saori; Sekine Mitsuo; Baba Sin-ichi; Kosugi Hiroki; Hosoyama Akira; Nagai Yoshimi; Sakai Mari; Ogura Keiko; Otsuka Rie; Nakazawa Hidekazu; Takamiya Minako; Ohfuku Yuhko; Funahashi Tomomichi; Tanaka Toshihiro; Kudoh Yutaka; Yamazaki Jun; Kushida Norihiro; Oguchi Akio; Aoki Ken-ichi; Yoshizawa Takio; Nakamura Yoshinobu; Robb Frank T.; Horikoshi Koki; Masuchi Yaeko; Shizuya Hiroaki; Kikuchi Hisasi 《DNA research》1998,5(2):55-76
The complete sequence of the genome of a hyper-thermophilicarchaebacterium, Pyrococcus horikoshii OT3, has been determinedby assembling the sequences of the physical map-based contigsof fosmid clones and of long polymerase chain reaction (PCR)products which were used for gap-filling. The entire lengthof the genome was 1,738,505 bp. The authenticity of the entiregenome sequence was supported by restriction analysis of longPCR products, which were directly amplified from the genomicDNA. As the potential protein-coding regions, a total of 2061open reading frames (ORFs) were assigned, and by similaritysearch against public databases, 406 (19.7%) were related togenes with putative function and 453 (22.0%) to the sequencesregistered but with unknown function. The remaining 1202 ORFs(58.3%) did not show any significant similarity to the sequencesin the databases. Sequence comparison among the assigned ORFsin the genome provided evidence that a considerable number ofORFs were generated by sequence duplication. By similarity search,11 ORFs were assumed to contain the intein elements. The RNAgenes identified were a single 16S-23S rRNA operon, two 5S rRNAgenes and 46 tRNA genes including two with the intron structure.All the assigned ORFs and RNA coding regions occupied 91.25%of the whole genome. The data presented in this paper are availableon the internet at http://www.nite.go.jp. 相似文献