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1.
Motohiko Takemura Hiroyuki Fukui Yohichi Yamamoto Naohiro Hosomi Hiroshi Wada 《Journal of neurochemistry》1987,48(4):1185-1190
The nitrendipine receptor associated with the voltage-dependent calcium channel in rat brain was solubilized by detergent extraction and sonication. The detergent solution used for extraction consisted of 10 mM 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), 0.25% (wt/vol) polyoxyethylene 20 cetyl ether (Brij 58), and 0.025% (wt/vol) polyoxyethylene 17 cetyl stearyl ether (Lubrol WX) in the presence of 30% (wt/vol) glycerol as a stabilizer. The molecular weight of the receptor was estimated to be 1,800K by Sephacryl S-500 gel filtration and 800K by sucrose density gradient sedimentation. The equilibrium dissociation constant of [3H]nitrendipine to the solubilized receptors was 5.6 nM, which is approximately 10 times that of the membrane-bound receptor. The binding of nitrendipine to the receptor was inhibited noncompetitively by the structurally unrelated calcium channel inhibitors verapamil and prenylamine; their concentrations for 50% inhibition were both 1.0 X 10(-7) M, and they caused maximal inhibitions of 70 and 100%, respectively. 相似文献
2.
Isolation and characterization of 101-beta-lysozyme that possesses the beta-aspartyl sequence at aspartic acid-101 总被引:1,自引:0,他引:1
H Yamada T Ueda R Kuroki T Fukumura T Yasukochi T Hirabayashi K Fujita T Imoto 《Biochemistry》1985,24(27):7953-7959
In the reaction of the intramolecular cross-linking between Lys-13 (epsilon-NH3+) and Leu-129 (alpha-COO-) in lysozyme using imidazole and 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide hydrochloride [Yamada, H., Kuroki, R., Hirata, M., & Imoto, T. (1983) Biochemistry 22, 4551-4556], it was found that two-thirds of the protein (both the recovered and cross-linked lysozymes) showed a lower affinity than the rest against chitin-coated Celite, an affinity adsorbent for lysozyme. The protein with the reduced affinity was separated on chitin-coated Celite affinity chromatography and found to be slightly different from native lysozyme in the elution position of the tryptic peptide of Ile-98-Arg-112 on reversed-phase high-performance liquid chromatography. In contrast with native lysozyme, the limited hydrolysis of this abnormal tryptic peptide of Ile-98-Arg-112 in 6 N HCl at 110 degrees C gave a considerable amount of beta-aspartylglycine. Therefore, it was concluded that two-thirds of the protein obtained from this reaction possessed the beta-aspartylglycyl sequence at Asp-101-Gly-102. As a result, we obtained four lysozymes from this reaction, the derivative with the beta-aspartyl sequence at Asp-101 (101-beta-lysozyme), the cross-linked derivative between Lys-13 and Leu-129 (CL-lysozyme), the CL-lysozyme derivative with the beta-aspartyl sequence at Asp-101 (101-beta-CL-lysozyme), and native lysozyme. In the ethyl esterification of Asp-52 in lysozyme with triethyloxonium fluoroborate [Parsons, S. M., Jao, L., Dahlquist, F. W., Borders, C. L., Jr., Groff, T., Racs, J., & Raftery, M. A. (1969) Biochemistry 8, 700-712; Parsons, S. M., & Raftery, M. A. (1969) Biochemistry 8, 4199-4205], the same bond rearrangement was detected in the same ratio.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Summary Maximum production of alkaline serine protease by Bacillus alcalophilus subsp. halodurans KP 1239 was achieved after 24 h cultivation, at an initial pH of 7.6, on a medium containing 1.0% sodium citrate, 0.3% yeast extract, and 0.3% KH2PO4. The enzyme was purified to crystalline form from culture broth. The enzyme was most active at 60° C and at pH 11.5. The molecular weight, isoelectric point and sedimentation coefficient in water at 20° C were estimated as 29 000, 8.8 and 3.3S, respectively. The N-terminal amino acid sequence was Ala-Gln-Ser-Val-Pro-Trp-Gly-Ile-Ser-Arg-Val-Gln-Ala-Pro-Ala-Ala-His-Asn-Arg-Gly-. The enzyme shared its antigenic determinants with B. alcalophilus ATCC 21522 serine protease, but not with the subtilisins Carlsberg and BPN.
Offprint requests to: Yuzuru Suzuki 相似文献
4.
Light-enhanced active pyruvate uptake into mesophyll chloroplastsof C4 plants was reported to be mimicked by either of the twotypes of cation jump: H+-jump in maize and phylogenically relatedspecies (H+-type) and Na+-jump in all the other C4 species tested(Na+-type) [Aoki, N., Ohnishi, J. and Kanai, R. (1992) PlantCell Physiol. 33: 805]. In this study, medium and stromal pH was monitored in the suspensionof C4 mesophyll chloroplasts. Medium alkalization lasting for5 to 10 seconds after pyruvate addition was detected by a pHelectrode and observed only in the light and only in mesophyllchloroplasts from H+-type species, Zea mays L. and Coix lacryma-jobiL., but not in those from Na+-type species Panicum miliaceumL., Setaria italica (L.) Beauv. and Panicum maximum Jacq. Theinitial rate of H+ consumption showed good correlation with[14C]pyruvate uptake measured by silicone oil filtering centrifugation,both being inhibited by N-ethylmaleimide and 7-chloro-4-nitrobenzo-2-oxa-l,3-diazole to the same degree. The ratio of the rate of H+ uptaketo that of pyruvate uptake was always about 1. Pyruvate-inducedacidification of the stroma was observed in maize mesophyllchloroplasts. These results show one to one cotransport of H+and pyruvate anion into mesophyll chloroplasts of H+-type C4species in the light. (Received January 5, 1994; Accepted May 6, 1994) 相似文献
5.
Shimomura Shoji; Liu Wei; Inohara Naohiro; Watanabe Shinichiro; Futai Masamitsu 《Plant & cell physiology》1993,34(4):633-637
A genomic clone encoding an auxin-binding protein (ABP) fromthe endoplasmic reticulum was isolated from Arabidopsis thaliana.The ABP gene consisted of 5 exons and 4 introns and encodeda polypeptide of 198 residues. A gene encoding the 7SL RNA ofthe signal recognition particle was located downstream of theABP gene.
4Recipient of a scholarship from the National Education Commission,People's Republic of China. 相似文献
6.
Mapping of replication initiation site in Mycoplasma capricolum genome by two-dimensional gel-electrophoretic analysis. 总被引:3,自引:0,他引:3
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The homolog of the dnaA gene, which has been reported to be present in the vicinity of the initiation site of replication in the genome of Mycoplasma capricolum (M.Miyata, L.Wang, and T.Fukumura, J. Bacteriol. 175: 655-660, 1993) was mapped precisely. A 9540-bp region containing the dnaA gene was cloned and the entire region was sequenced with the exception of a previously reported region of 2517 bp (Fujita, M.Q., Yoshikawa, H. and Ogasawara, N. Gene 93: 73-78, 1992). The organization of the 9540-bp region was compared with that of corresponding regions in other bacteria. The arrangement and directions of rnpA, rpmH, dnaA, dnaN were conserved, but no other open reading frames were found that were homologous to those that are commonly found around dnaA genes in other bacteria. The directions of movement of the replication fork around the dnaA gene were analyzed by neutral/alkaline two-dimensional gel electrophoresis. The forks developed in a 1569-bp region that consisted of the dnaA structural gene and its downstream non-coding region, and then they proceeded bidirectionally. 相似文献
7.
Abstract Polymerase chain reaction was carried out to amplify the conserved region (789 bp in the case of Mycoplasma capricolum ) of the dnaA gene (1350 bp in the case of M. capricolum ) of 15 representatives of the class Mollicutes using degenerate oligonucleotide primers. The dnaA gene fragments were amplified from M. mycoides subsp. capri, Spiroplasma apis and S. citri . The amino acid sequences deduced from the nucleotide sequences of the amplified fragments showed very low similarities to those of the corresponding regions of four walled bacteria. The values of similarity between any two of the three mollicute species were lower than those between any two of the four walled bacteria. 相似文献
8.
Takahiro Okazaki Chiemi Nakanishi-Ito Naohiro Seo Takae Tanino Masafumi Takiguchi Kohji Egawa 《Cancer immunology, immunotherapy : CII》1993,36(2):83-88
Tumor-specific expression of Qa-2k antigen coded by the Q5k gene on various mouse tumor cells and immunological response of the host mice to the antigen have been demonstrated [Seo et al. (1992) J Exp Med 175: 547; Tanino et al. (1992) Cancer Immunol Immunother 35: 230]. The possibility was examined that Qa-2 antigen is one of the recognition target molecules of immunopotentiator-induced, H-2-nonrestricted tumoricidal lymphocytes of Qa-2– mice. Lymphocytes stimulated in vivo withP. acnes or culture-induced anomalous killers of B6.K1 mice did not exhibit significant in vitro cytotoxicity against B6.K1 lymphoblasts but lysed their Qa-2,3-congenic counterpart B6 lymphoblasts. To demonstrate the Qa-2 specificity of such cytotoxic cells more precisely, an L cell transformant clone (LQ7b/Kb), which expressed the 1 and 2 domains of the Qa-2 antigen (Q7b gene product), was generated by transfecting a cloned plasmid DNA containing a hybrid gene constructed from the 5 half of the Q7b gene and the 3 half of the H-2Kb gene (pQ7b/Kb). Using LQ7b/Kb cells as the target cells and the nylon-wool-nonadherent fraction of lymphocytes fromP. acnes-stimulated (C3H/He × B6.K1)F1 mice (H-2k, Qa-2–) as the effector cells of the in vitro cytotoxicity reaction, the presence of cytotoxic cells that recognize the 1/2 region of the Q7b gene product was demonstrated. The cytotoxic activity was dependent on T cells bearing T cell receptors of the / type (TCR/). The (C3H/He × B6.K1)F1 effector cells, as well as the B6.K1 effector cells also lysed BW5147 lymphoma cells (Qa-2k+) derived from AKR mice (Qa-2–, H-2k). By target-competition experiments it was shown that some of the effector cells lytic to BW5147 were identical to those that lysed LQ7b/Kb. Therefore some of the tumoricidal cells induced by the immunopotentiator interact with the target tumor cells through recognition of the 1/2 region of the Qa-2k tumor antigen by TCR/. 相似文献
9.
Isao Sakita Takushi Monden Hirohito Nagaoka Yoshihiro Katsumoto Taro Wakasugi Naohiro Tomita Tsutomu Takeda Tetsuro Kobayashi Takashi Shimano Takesada Mori 《Biotherapy》1993,6(2):103-112
We have previously reported that the antitumor effect of OK-432, a streptococcal preparation, is markedly augmented when injected intratumorally together with fibrinogen (OK-432/fbg) [1]. In order to elucidate the effects of this immunotherapy on regional lymph nodes (RLN), we carried out both morphological and functional analyses of the RLN from colonic cancer patients treated with OK-432/ fbg. Computer-aided morphometry revealed that the maximal cross-sectional areas and the broadest diameters of the RLN were significantly greater (p<0.01) in patients who had undergone local immunotherapy than in patients who had not. The component structures of RLN, such as sinus, follicle and paracortex, were all enlarged in the OK-432/fbg-treated patients, and necrosis of metastatic tumors was observed. RLN lymphocytes recovered from OK-432/fbg treated patients showed elevated reactivity to phytohemagglutinin (PHA) and the stimulation index was clearly higher than that of control patients. Flow cytometric analysis revealed a predominance of T-cells, especially CD4 subsets, and higher positivity for both CD25 and HLA-DR. Furthermore, RLN lymphocytes killed more effectively K562 and Daudi cells in the patients who had had immunotherapy. These results suggest that the effect of local immunotherapy with OK-432/fbg is not restricted to the site of injection but extends to the lymph nodes, and contributes to tumor regression through the augmentation of cellular immunity.Abbreviations RLN
regional lymph node(s)
- OK-432/fbg
OK-432/fibrinogen solution
- PHA
phytohemagglutinin
- NK
natural killer
- LAK
lymphocyte activated killer 相似文献
10.
Chang Gong Ziliang Cheng Yaping Yang Jun Shen Yingying Zhu Li Ling Wanyi Lin Zhigang Yu Zhihua Li Weige Tan Chushan Zheng Wenbo Zheng Jiajie Zhong Xiang Zhang Yunjie Zeng Qiang Liu R.Stephanie Huang Andrzej L.Komorowski Eddy S.Yang Fran?ois Bertucci Francesco Ricci Armando Orlandi Gianluca Franceschini Kazuaki Takabe Suzanne Klimberg Naohiro Ishii Angela Toss Mona P.Tan Mathew A Cherian Erwei Song 《中国科学:生命科学英文版》2022,65(11):2205-2217
Patients with hormone receptor(HR)-positive tumors breast cancer usually experience a relatively low pathological complete response(p CR) to neoadjuvant chemotherapy(NAC). Here, we derived a 10-micro RNA risk score(10-mi RNA RS)-based model with better performance in the prediction of p CR and validated its relation with the disease-free survival(DFS) in 755 HRpositive breast cancer patients(273, 265, and 217 in the training, internal, and external validation sets, respectively). This model,pres... 相似文献