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951.
N Li Y Hashimoto S Adnan H Miura H Yamamoto T Ezaki 《International journal of systematic bacteriology》1992,42(4):602-605
We describe three new species of the genus Peptostreptococcus which were isolated from human specimens and were tentatively identified as Peptostreptococcus prevotii. These three organisms were not homologous with previously described type strains of the genus Peptostreptococcus. A total of 12 strains that were identified biochemically as P. prevotii were divided into five independent DNA similarity groups; 10 of these strains were divided into three similarity groups which exhibited significant phenotypic differences from previously described species. Therefore, we propose the following new species: Peptostreptococcus vaginalis for group 1 strains, Peptostreptococcus lacrimalis for group 2 strains, and Peptostreptococcus lactolyticus for group 3 strains. The type strain of P. vaginalis is strain GIFU 12669 (= JCM 8138), the type strain of P. lacrimalis is strain GIFU 7667 (= JCM 8139), and the type strain of P. lactolyticus is strain GIFU 8586 (= JCM 8140). 相似文献
952.
953.
H. Hashimoto 《Protoplasma》1992,167(1-2):88-96
Summary Studies have been made of whether actin filaments and microtubules are involved in the chloroplast division ofClosterium ehrenbergii (Conjugatae). Fluorostaining with rhodamine-phalloidin showed 5 types of localization of F-actin: (1) cables of actin filaments running in the cortical cytoplasm along the cell's long axis, (2) condensed actin filaments at the septum, (3) perinuclear distribution of actin filaments, (4) F-actins in a marking pin-like configuration adjacent to the nucleus of semicells just before completion of chloroplast kinesis, and (5) actin filaments girdling the isthmus of the constricted and dividing chloroplasts. Cytochalasin D (CD) at a concentration of 6 to 25 M caused significant disruption of actin filaments and the arrest of chloroplast kinesis, nuclear division, septum formation and cytoplasmic streaming within 3 to 6h. Chloroplast kinesis and cytoplasmic streaming recovered when cells were transferred to the medium without CD after CD treatment, or were subjected to prolonged contact with CD for more than 9h. In these cells there was a coincidental reappearance of actin filaments. A tubulin inhibitor, amiprophos-methyl at 330 M, did not inhibit chloroplast kinesis but did inhibit division and positioning of the nucleus. These results suggest that actin filaments do play a role in the mechanism of chloroplast kinesis but that microtubules do not appear to be involved in the process.Abbreviations APM
amiprophos-methyl
- CD
cytochalasin D
- DAPI
4,6-diamidino-2-phenylindole
- DIC
Nomarski differential interference contrast
- DMSO
dimethyl sulfoxide
- Rh-Ph
rhodamine-phalloidin 相似文献
954.
Go Kawaguchi William H. Hildebrand Masaki Hiraiwa Sachiko Karaki Takeshi Nagao Nobuo Akiyama Hisanori Uchida Kouichi Kashiwase Tatsuya Akaza Robert C. Williams Takeo Juji Peter Parham Masafumi Takiguchi 《Immunogenetics》1992,37(1):57-63
Newly defined antigens of the B5, B35 cross-reacting group have been found in Japanese and North American Indians. Nucleotide sequencing of the alleles encoding the Japanese B5.35 antigen and the variant B5 antigen from the Piman Indians show them to be identical. This new allele, B
*
5102, differs from B
*
5101 by a single nucleotide substitution that changes residue 171 from histidine to tyrosine. Residue 171, which is part of the 2 helix, is believed to contribute directly to peptide interaction in the A pocket of the binding groove and is either histidine or tyrosine in all HLA-A, B, C heavy chains. Tyrosine 171 is shared by B
*
5102, B
*
3501, B
*
3502, and B
*
5301 and must be responsible for the serological cross-reactivities of these molecules not shared with B
*
5101. Stimulation of lymphocytes from a B
*
5101 positive donor with B
*
5102 positive cells failed to generate cytotoxic T cells with specificity for the difference between these molecules. However, one out of five clones of cytotoxic T cells raised against B
*
5101 failed to lyse targets expressing B
*
5102. Substitution of histidine for tyrosine at residue 171 affected recognition of HLA-B35-restricted human minor histocompatibility antigen-specific T cell clones.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession number M68964. 相似文献
955.
C Kiiyukia A Nakajima T Nakai K Muroga H Kawakami H Hashimoto 《Applied and environmental microbiology》1992,58(9):3078-3082
A fish pathogen, Vibrio cholerae non-O1, was isolated from diseased ayu fish (Plecoglossus altivelis) collected from rivers in eight prefectural districts of Japan. This organism was found to have biochemical characteristics similar to those of V. cholerae non-O1, except that our isolates were negative for ornithine decarboxylase. Antiserum against an ayu isolate did not agglutinate with the majority of environmental V. cholerae non-O1 isolates, but a major O antigen was common among the ayu isolates. All strains were hemolytic to sheep erythrocytes, and oral administration of culture supernatants induced fluid accumulation in suckling mice. However, the crude toxin was not lethal to adult mice, and no cholera toxin-like enterotoxins were detected. 相似文献
956.
The growth inhibitory activities of 6 endogenous growth inhibitors isolated from light-grown dwarf peas (Pisum sativum cv. Progress No. 9) were examined in the epicotyl of dark-grown seedlings of the same cultivar in the dark in order to examine the possible contribution of these compounds to the growth inhibition brought about by red light. The activities of these natural inhibitors, including two A-2 and A-2 of as yet undetermined structure, were compared with those of synthetic growth retardants and benzyladenine. Samples were applied directly into the epicotyls via a glass capillary tube. In 24-h tests doses for a 25% inhibition (I25) were: A-2, 4.3 × 10-2: cis-xanthoxin, 1.2 × 10-1 ; A-2, 1.6 × 10-1; trans-xanthoxin, 1.2; R,S-dihydromaleimide, 3.5 × 102 and pisatin, 4.0 × 102 nmol plant-1 . In 72-h tests, I25's were: benzyladenine, 1.5; AMO-1618 (ammonium-(5-hydroxycarvacryl)-trimethylchloride piperidine carboxylate), 2.4; R,S-dihydromaleimide, 4.0 × 102 and CCC (chlorocholine chloride), 1.1 × 103 nmol plant-1. -D-Glucosyl-R-dihydromaleimide had no activity at all. Benzyladenine caused the thickening as well as elongation inhibition of the epicotyls of intact plants. The possible involvement of A-2 and in the red light growth inhibition of dwarf peas is discussed.Abbreviations AMO-1618
ammonium-(5-hydroxycarvacryl)-trimethylchloride piperidine carboxylate
- CCC
chlorocholine chloride
- G-DHMD
-D-glucosyl-R-dihydromaleimide
- I25
dose required for a 25% growth inhibition
- R
red light
author for correspondence 相似文献
957.
T Fukao S Yamaguchi S Tomatsu T Orii G Frauendienst-Egger L Schrod T Osumi T Hashimoto 《Biochemical and biophysical research communications》1991,179(1):124-129
The molecular basis of 3-ketothiolase deficiency (3KTD) was examined in a 3KTD family. Immunochemical analyses showed that mitochondrial acetoacetyl-CoA thiolase (T2) biosynthesized in the patient's fibroblasts (GK06) was unstable and that the parents and brother were obligatory carriers of 3KTD. When sequencing the PCR-amplified patient's T2 cDNA, we noted a G to A replacement which caused 347Ala to Thr substitution of the mature T2 subunit. Transfection analysis revealed that this substitution resulted in an instability of the T2 protein. Analyses of the T2 cDNA and gene of the family indicated that the patient was a compound heterozygote; the allele that derived from the mother had a point mutation (347Ala to Thr) and the other allele from the father has a mutation which would abolish the T2 gene expression. This report is apparently the first definition of a mutant allele for 3KTD, at the gene level. 相似文献
958.
Different effects of DNA adducts induced by carcinogenic and noncarcinogenic azo dyes on in vitro DNA synthesis 总被引:1,自引:0,他引:1
M Kojima M Degawa Y Hashimoto M Tada 《Biochemical and biophysical research communications》1991,179(2):817-823
M13mp10 phage DNA modified with the carcinogen 3-methoxy-4-aminoazobenzene (3-MeO-AAB) or the noncarcinogen 2-methoxy-4-aminoazobenzene (2-MeO-AAB) was used as a template for E.coli DNA polymerase I. Analysis of the reaction products on DNA sequencing gels showed that with both types of compound the induced lesions blocked DNA synthesis, mainly at one base prior to guanine adducts, but that the inhibition by 3-MeO-AAB-adducts was substantially greater than that by 2-MeO-AAB-adducts. Thus different effects on DNA replication between 3-MeO-AAB- and 2-MeO-AAB-adducts might be a reflection of differences in their carcinogenic potency. 相似文献
959.
Cloning and characterization of an amidase gene from Rhodococcus species N-774 and its expression in Escherichia coli 总被引:3,自引:0,他引:3
Y Hashimoto M Nishiyama O Ikehata S Horinouchi T Beppu 《Biochimica et biophysica acta》1991,1088(2):225-233
For investigation of an unknown open reading frame which is present upstream of the nitrile hydratase (NHase) gene from Rhodococcus sp. N-774, a longer DNA fragment covering the entire gene was cloned in Escherichia coli. Nucleotide sequencing and detailed subcloning experiments predicted a single open reading frame consisting of 521 amino acid residues of Mr 54,671. The amino acid sequence, especially its NH2-terminal portion, showed significant homology with those of indoleacetamide hydrolases from Pseudomonas savastanoi and Agrobacterium tumefaciens, and acetamidase from Aspergillus nidulans. The 521-amino acid coding region was therefore expressed by use of the E. coli lac promoter in E. coli, and was found to direct a considerable amidase activity. This amidase hydrolyzed propionamide efficiently, and also hydrolyzed, at a lower efficiency, acetamide, acrylamide and indoleacetamide. These data clearly show that the unknown open reading frame present upstream of the NHase coding region encodes an amidase. Because the TAG translational stop codon of the amidase is located only 75 base pairs apart from the ATG start codon of the alpha-subunit of NHase, these genes are probably translated in a polycistronic manner. 相似文献
960.
Hidenobu Okumura Kunio Matsumto Koji Hashimoto Kunihiko Yoshikawa 《Experimental cell research》1991,192(2):647-650
Involucrin is a precursor protein of detergent-insoluble cornified envelope and a marker of terminal differentiation of epidermal keratinocytes. To quantify differentiation of cultured human keratinocytes, the population of involucrin-positive cells was estimated by immunofluorescent staining using anti-involucrin antibody and flow cytometry. Normal human keratinocytes were cultured under three conditions for induction of differentiation: low Ca2+ concentration (0.1 mM Ca2+), high Ca2+ concentration (1.8 mM Ca2+), and high Ca2+ concentration with 10% fetal bovine serum (FBS). The relationship between fluorescence intensity and involucrin synthesis was confirmed by visual examination of sorted cells. The population of involucrin-positive cells increased from 7.2 to 18.1% by elevating Ca2+ concentration and to 37.0% by adding FBS. The extent of cornified envelope formation under the same culture conditions was consistent with the estimation of involucrin-positive cells. The cytofluorographic analysis of involucrin synthesis made it possible to determine the number of differentiated cells in a large number of samples precisely and reliably. Thus, it is a useful method for quantifying keratinocyte differentiation. 相似文献