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81.
T Kataoka S Yamamoto T Yamamoto T Tokunaga 《Japanese journal of medical science & biology》1990,43(5):171-182
In vivo antitumor activity of a deoxyribonucleic acid fraction obtained from Mycobacterium bovis BCG (named MY-1) increased when it was complexed with poly-L-lysine (poly LL) solubilized by addition of carboxymethylcellulose (CMC). The complex of MY-1 and poly LL/CMC induced interferon in vivo at a low dose of MY-1 which alone exerted no IFN induction. With Line 10 hepatoma (L10) which is syngeneic with strain 2 guinea pigs, it was demonstrated that repeated intralesional injections of the complex resulted in delay of tumor growth and complete cure of animals from L10 tumor inoculated. Similar treatment of the animals with the same amount of MY-1 or poly LL/CMC alone had little therapeutic effect on the tumor growth. 相似文献
82.
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
83.
T Sueyoshi M Uwani N Itoh H Okamoto T Muta F Tokunaga K Takada S Iwanaga 《The Journal of biological chemistry》1990,265(17):10030-10035
It has been proposed that a cysteine proteinase inhibitor (CPI) found in the ascitic fluid of Sarcoma 180 tumor-bearing mice is a kind of kininogen (Itoh, N., Yokota, S., Takagishi, U., Hatta, A., and Okamaoto, H. (1987) Cancer Res. 47, 5560-5565). The first 40 NH2-terminal residues and 54 residues of the COOH-terminal sequence, including the bradykinin moiety of highly purified ascites CPI, were determined and compared with those of mammalian low molecular weight kininogens (LMWK). The significant identity between these amino acid sequences with those of other mammalian LMWKs suggests that ascites CPI corresponds precisely to mouse LMWK. This kininogen has a light chain composed of 43 amino acid residues, which contains a unique Met-Ala-Arg-bradykinin sequence. Hydroxyproline, which was recently identified in the bradykinin sequence of kininogen from the ascitic fluid of a cancer patient, was not found in the kinin moiety of this mouse kininogen. Among purified glandular kallikreins from human, hog, rat, and mouse, only mouse submaxillary gland kallikrein was able to release bradykinin from this kininogen. Kinetic studies using a newly synthesized fluorogenic substrate, N-t-butoxycarbonyl-Met-Ala-Arg-MCA, revealed that mouse kallikrein hydrolyzes this substrate approximately 80-fold faster than does hog kallikrein, suggesting that the unique Met-Ala-Arg-bradykinin sequence is responsible for the varied susceptibility of mouse kininogen to different kallikreins. 相似文献
84.
Summary The distribution of phenotypes controlled by three HLA-linked loci BF, C2, and GLO has been studied in Japanese patients with insulin-dependent diabetes mellitus (IDDM). A slight but significant higher incidence of a rare varian BF
*FT (=*
F075) in patients was confirmed in the combined data with our previous study (Tokunaga et al. 1981 b). No significant association of C2 and GLO alleles with IDDM was found. 相似文献
85.
The complete nucleotide sequence of a 16S ribosomal RNA gene from tobacco chloroplasts has been determined. This nucleotide sequence has 96% homology with that of maize chloroplast 16S rRNA gene and 74% homology with that of Escherichia coli16S gene.The 3′ terminal region of this gene contains the sequence ACCTCC which is complementary to sequences found at the 5′ termini of prokaryotic mRNAs.The large stem and loop structure can be constructed from the sequences surrounding the 5′ and 3′ ends of the 16S gene. These observations demonstrate the prokaryotic nature of chloroplast 16S rRNA. 相似文献
86.
Physical mapping of the genome and sequence analysis at the inverted terminal repetition of adenovirus type 4 DNA 总被引:3,自引:0,他引:3
The genome of adenovirus type 4 (Ad4), the unique member of Ad group E, has been mapped with nine restriction endonucleases. Comparison of the occurrence of restriction endonuclease cleavage sites on Ad2, Ad7, Ad12 and Ad4 indicates that there is very little homology between these serotypes. Sequence analysis at the ITR of Ad4 showed that the "CAT" box which is present in all the ITRs of Ad's so far sequenced is absent in Ad4. The length of 116 bp for the ITR of Ad4 is also different from that of other Ad subgroups. 相似文献
87.
Kunie Yoshikawa Takehiko Nohmi Rumiko Miyata Motoi Ishidate Jr. Naoki Ozawa Masakazu Isobe Tadashi Watabe Tuneo Kada Takashi Kawachi 《Mutation research》1982,96(2-3)
Comparison studies for detecting differences between liver microsome and S9 preparations from 4 strains (Donryu, Fischer, Sprague-Dawley, Wistar) of young male rats were carried out with pretreatment of the animals by inducers such as PCBs and PB plus 5,6-BF. Each microsome fraction was assayed for the enzymic activity of metabolism of model substrates such as aniline, benzophetamine, BP, DMN and 7-ethoxycoumarin. The hepatic S9 sample was also compared, as regards its metabolizing ability to activate 9 pre-mutagens (2AA, AAF, o-AAT, BP, DAB, DMBA, DMN, m-PDA, quinoline) to directly acting mutagens in the Salmonella/hepatic S9 activation test by using TA98, TA100 and TA1537 strains with or without cytochrome P450 inhibitors (SKF-525A, metyrapone, 7,8-benzoflavone).In the enzymic assay with PCBs-induced microsomes, BP hydroxylation revealed a strain-specific difference: the microsomes from Fischer and Wistar rats were more effective for metabolizing BP than those from the other strains of rat. The effect of induction by PB plus 5,6-BF for Fischer rats showed relatively higher enzymic activity in the same induction group. Other microsomes prepared from rats with and without induction by PB plus 5,6-BF did not show a clear-cut strain dependency in the enzymic activities assayed.In the mutation experiments with hepatic S9 samples, the examination of DAB and quinoline revealed a marked strain difference when S9 samples prepared from PCBs-pretreated and PB-plus-5,6-BF-induced rats were used: the S9 sample from Fischer rats was available for activating the two pre-mutagens to directly acting mutagens. No marked difference in the metabolic activation of the remaining 7-pre-mutagens was observed on other S9 preparations.In examinations of mutagenicity activities with the use of three inhibitors, the two S9 preparations made with the two induction methods showed inhibition profiles closely similar to each other. However, there were minor differences in the profiles by these inhibitors.From these findings it was concluded that Fischer rat-liver S9 is useful for detecting mutagens in the metabolic activation test, when induction by PB plus 5,6-BF was used in the Ames Salmonella test. 相似文献
88.
Tatsuo Iwasa Kazuo Takeda Fumio Tokunaga Peter S. Scherrer Lester Packer 《Bioscience reports》1982,2(11):949-958
To elucidate the role of tyrosine residues in the shift of max and the light-driven proton pump of bacteriorhodopsin~ the photochemical reaction of tyrosine-iodinated bacteriorhodopsin (tyr-mod-bR) was investigated by low-temperature spectrophotometry. After 4–5 of 11 tyrosine residues of bacteriorhodopsin were iodinated, the meta-intermediate of tyr-mod-bR in 75% glycerol solution became so stable that its decay could be observed even at room temperature and i t was stable in the dark for several hours at –65°C.Four batho-intermediates were formed by irradiation with green light (500 nm) at –170°C. Like native bacteriorhodopsin, these batho-intermediates were photoreversible at –170°C. Four corresponding meta-intermediates were also formed by irradiation at –60°C. Using the difference spectra between meta-intermediates and tyr-mod-bR, the absorption spectra of four kinds of tyr-mod-bRs, batho-intermediates, and meta-intermediates were estimated. Each was at shorter wavelengths than that of its corresponding type in native bacteriorhodopsin. The results indicate that two or more tyrosine residues have some role in determining color in native bacteriorhodopsin. 相似文献
89.
Characterization of porins from the outer membrane of Salmonella typhimurium. 1. Chemical analysis. 总被引:5,自引:0,他引:5
The three species of channel-forming outer membrane proteins, porins, have been purified to homogeneity from mutant strains of Salmonella typhimurium which produce single species of porin. Purification was by stepwise solubilization with dodecylsulfate or guanidine thiocyanate, gel filtration, and preparative gel electrophoresis. Amino acid compositions and tryptic peptide maps of the three species of porins showed close resemblance, but at the same time clear differences among them. The number of amino acid residues in the porins purified from the strains SH5551, SH6377 and SH6017 were 361, 354 and 345, and their calculated molecular weights 39800, 39300 and 38000, respectively. Amino-terminal and carboxyl-terminal amino acids in all three species of porins appeared to be alanine and phenylalanine, respectively. Neither half-cystine nor hexosamine was found in these preparation of porins. The isoelectric points of porins from the strains SH5551, SH6377 and SH6017, determined by isoelectric focusing, showed slight differences from each other. These results, and the genetic experiments from another laboratory, suggest that the three species of porins in Salmonella typhimurium are distinct polypeptides, probably coded for by distinct structural genes, which might have been derived from the same ancestral gene. 相似文献
90.
Dissociability of the monomer ribosomes prepared from dry and imbibed pine (Pinus thunbergii) seed embryos was analyzed in sucrose density gradient containing a high salt buffer. Abnormal dissociation into the subunits
was observed with the ribosome preparation from dry seed embryos when compared with that from imbibed seed embryos, i.e. each
subunit peak was broader and localized at a lower site in sucrose density gradient. This indicates some change(s) in ribosomes
during imbibition of seeds. These ribosomal changes also progressedin vitro. That is, after incubation of ribosome preparation from dry seed embryos in a high salt buffer for 5 min at 30 C or in a
low salt buffer for 15 hr at 0 C, complete dissociation into the normal subunits was observed. No difference was found between
polyacrylamide gel electrophoresis patterns of ribosomal RNA from dry and imbibed seed embryos. These results suggest some
alteration in the protein components of ribosome during imbibition of pine seeds.
This paper is dedicated to Prof. Shyogo Sawamura, Utsunomiya University on his retirement in March, 1979. 相似文献