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11.
Mutants of Group D1Salmonella Carrying the Somatic Antigen of Group A Organisms: Isolation and Serological Characterization 总被引:2,自引:2,他引:0
O antigen mutants were obtained from Salmonella durban, a group D(1) organism, by treatment with N-methyl-N'-nitro-N-nitrosoguanidine. Serological studies demonstrated that the mutants lost the O-9 antigen factor of the parent organism but acquired the O-2 factor specific to group A Salmonella. Lipopolysaccharides of the mutant strains contained paratose which determines the specificity of O-2 factor. Tyvelose, present in the wild-type lipopolysaccharide, was not found in the mutants. H antigens and other biological characteristics of the mutant strains were the same as those of the wild-type organism. The present finding implies that group A Salmonella species might be derived from group D(1) organisms. 相似文献
12.
Mutants of Group D1Salmonella Carrying the Somatic Antigen of Group A Organisms: Evidence for the Lack of Cytidine Diphosphate Paratose-2-Epimerase Activity 总被引:3,自引:3,他引:0 下载免费PDF全文
The mutant strains of Salmonella durban that possessed O antigen 2, 12 of group A Salmonella were defective in the cytidine diphosphate paratose-2-epimerase activity. The enzyme preparation of the mutant strains catalyzed the conversion of cytidine diphosphate glucose into cytidine diphosphate paratose but not into cytidine diphosphate tyvelose. The defect in the epimerase activity was also confirmed by the use of purified cytidine diphosphate paratose as a substrate. The specificity of dideoxyhexosyl transferase catalyzing the formation of the group-specific determinant is discussed. 相似文献
13.
Takahiro Tsukahara 《Primates; journal of primatology》1990,31(2):147-156
Grooming initiation among adult males and females of a Japanese macaque troop was analyzed during the non-mating season. Some
gestures (“solicitation”) elicited grooming from partners at a high rate. Grooming initiation patterns were divided into two
main types: (1) a male often solicited a female to groom him immediately after approaching her and was groomed by her; and
(2) a female approached an alpha male selectively, and immediately groomed him. After a female groomed a male, she rarely
solicited him to groom her and instead often moved away from him. These results indicated that males were motivated to be
groomed, while females were more highly motivated to groom. Sex differences in grooming motivation can be explained by sex
differences in the benefit to be groomed. 相似文献
14.
The complete amino acid sequence of myoglobin from the triturative stomach of gastropodic molluscBursatella leachii has been determined. It is composed of 146 amino acid residues, is acetylated at the N-terminus, and contains a single histidine residue at position 95 which corresponds to the heme-binding proximal histidine. The E7 distal histidine, which is conserved widely in myoglobins and hemoglobins, is replaced by valine inBursatella myoglobin. The amino acid sequence ofBursatella myoglobin shows strong homology (73–84%) with those ofAplysia andDolabella myoglobins. 相似文献
15.
Hideki Fukuda Yuji Turugida Takahiro Nakajima Eiji Nomura Akihiko Kondo 《Biotechnology letters》1996,18(8):951-956
Summary Production of phospholipase D (PLD) by Streptoverticillium cinnamoneum immobilized within porous particles was investigated in repeated batch fermentation. The enzyme productivity in repeated batch fermentation was 2.2-fold that obtained in batch fermentation without immobilization, since many of the immobilized cells could be utilized as seed cells for each subsequent batch cycle. 相似文献
16.
Expression of NADH-Dependent Glutamate Synthase in Response to the Supply of Nitrogen in Rice Cells in Suspension Culture 总被引:2,自引:0,他引:2
Watanabe Sachiko; Sakai Takahiro; Goto Satoshi; Yaginuma Toshiko; Hayakawa Toshihiko; Yamaya Tomoyuki 《Plant & cell physiology》1996,37(7):1034-1037
The effects of inorganic and organic nitrogen on the levelsof mRNA for NADH-dependent glutamate synthase (GOGAT) and theprotein were examined in rice cells in suspension culture. Asupply of NH+4, NO-3, glutamine, or asparagine induced the accumulationof the protein and mRNA, but levels of mRNA for ferredoxin-GOGATwere hardly affected.
1Present address: P.C. Center Wakuya-cho, Toda-gun, Miyagi,Japan. 相似文献
17.
Tetsuo Ajiki Takahiro Fujimori Hideo Ikehara Yoichi Saitoh Sakan Maeda 《Biotechnic & histochemistry》1995,70(2):90-94
To investigate the relationship of oncogene analysis to morphology, we analyzed K-ras gene mutations by dot-blot hybridization with and without consideration of histological atypias in individual colorectal adenomas. Each of 54 colon polyps were divided into two parts after fixation. One part was used as a mass to assess point mutations; the remaining portion of each polyp was paraffin-embedded, stained with hematoxylin and eosin, and examined for point mutations related to histological atypias. In the first part of our study, K-ras gene mutations at codon 12 were detected in 13 cases (24%). In the second part of our study, 12 cases had distinctly different histological atypias. From each of these 12 cases, two areas, one with higher or one with lower grade atypia in the same polyp were excised to analyze for K-ras gene mutation. Two of these 12 cases (17%) had the mutation in different areas of the same tumor. These two cases contained the mutation only in the areas with higher grade atypia, and only one case added information regarding ras mutation upon microdissection when compared to the entire biopsy. These results suggest that oligonucleotide hybridization can identify the majority of cases containing ras mutations despite regional morphologic variation. Individual cases, however, may contain clonal subpopulations within adenomas with different ras sequences from other regions within the same adenoma. 相似文献
18.
Nagase Takahiro; Seki Naohiko; Tanaka Ayako; Ishikawa Ken-ichi; Nomura Nobuo 《DNA research》1995,2(4):167-174
In this series of projects regarding the accumulation of sequenceinformation of unidentified human genes, we newly deduced thesequences of 40 full-length cDNA clones of human cell line KG-1,and predicted the coding sequences of the corresponding genes,named KIAA0121 to 0160. The results of a computer search ofpublic databases indicated that the sequences of 13 genes wereunrelated to any reported genes, while the remaining 27 genescarried sequences which showed some similarities to known genes.Obvious unique sequences noted were as follows. A stretch oftriplet repeats was contained in each of three genes: Thesewere GAG(Glu) in KIAA0122 and KIAA0147, and TCC(Ser) in KIAA0150.A stretch of 10 amino acidresidues was repeated 21 times inKIAA0139, and a homologous sequence of 7678 nucleotideswas found repeated 6 times in the untranslated region of KIAA0125.northern hybridization analysis demonstrated that 13 genes wereexpressed in a cell- or tissue-specific manner. Although a vastnumber of expressed sequence tags (ESTs) have been registeredfor comprehensive analysis of cDNA clones, our sequence dataindicated that their distribution is very unbalanced: e.g. whileno EST hit 7 genes, 85 ESTs fell in a single gene. 相似文献
19.
The nucleotide sequences of 11 variable gene segments coding for rabbit T-cell receptor beta (Tcrb-V) chains were determined by directly sequencing fragments amplified by the cassette-ligation mediated polymerase chain reaction (CLM-PCR) and by modified anchor PCR without the cloning procedure. The nucleotide sequences in two of these 11 rabbit Tcrb-V gene segments coincided with those in two of the four rabbit Tcrb-V gene segments previously reported; the others have not been described. The percentage similarity of each nucleotide sequence of the 11 rabbit Tcrb-V gene segments was analyzed and the segments were divided into nine families, which were homologous to nine human families (Vb 2, 3, 4, 5, 7, 8, 10, 18, and 22), respectively.The nucleotide sequence data reported in this paper have been submitted to the DDBJ, EMBL, and GenBank nucleotide sequence databases and have been assigned the accession numbers D17416-D17426. 相似文献
20.
Takao Yagi Takahiro Yano Akemi Matsuno-Yagi 《Journal of bioenergetics and biomembranes》1993,25(4):339-345
A comparison of the mitochondrial NADH-ubiquinone oxidoreductase and the energy-transducing NADH-quinone oxidoreductase (NDH-1) ofParacoccus denitrificans revealed that both systems have similar electron-transfer and energy-transduction pathways. In addition, both complexes are sensitive to the same inhibitors and contain similar electron carriers, suggesting that theParacoccus NDH-1 may serve as a useful model system for the study of the human enzyme complex. The gene cluster encoding theParacoccus NDH-1 has been cloned and sequenced. It is composed of 18,106 base pairs and contains 14 structural genes and six unidentified reading frames (URFs). The structural genes, URFs, and their polypeptides have been characterized. We also discuss nucleotide sequences which are believed to play a role in the regulation of the NDH-1 gene cluster andParacoccus NDH-1 subunits which may contain the binding sites of substrates and/or electron carriers. 相似文献