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21.
Crystallographic studies of the chicken gizzard G-actin X DNase I complex at 5A resolution 总被引:5,自引:0,他引:5
N Sakabe K Sakabe K Sasaki H Kondo T Ema N Kamiya M Matsushima 《Journal of biochemistry》1983,93(1):299-302
The structure of the chicken gizzard G-actin X DNase I complex has been determined at 5 A resolution by an X-ray diffraction method. Protein phases were computed by the multiple isomorphous replacement method using four heavy atom derivatives. The mean figure of merit was 0.65. Dimensions of the three molecular species, the complex, G-actin and DNase I, were determined based on the "cypress wood" models derived from the electron density map. The natures of the heavy atom binding sites are discussed in relation to the distinction between the two component molecules. The pattern of successive contacts between actin molecules observed in the present crystal seems unrelated to that found in F-actin. 相似文献
22.
23.
K Suehiro S Kawabata T Miyata H Takeya J Takamatsu K Ogata T Kamiya H Saito Y Niho S Iwanaga 《The Journal of biological chemistry》1989,264(35):21257-21265
Factor IX BM Nagoya (IX Nagoya) is a natural mutant of factor IX responsible for severe hemophilia B. A patient with this mutant is characterized by a markedly prolonged ox brain prothrombin time. IX Nagoya was purified from the patient's plasma by immunoaffinity chromatography with an anti-factor IX monoclonal antibody column. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that treatment of IX Nagoya with factor XIa/Ca2+ resulted in cleavage only at the Arg145-Ala146 bond. Reversed-phase high performance liquid chromatography of a trypsin digest of IX Nagoya showed an aberrant peptide, which was further digested with proteinase Asp-N. Primary structure analysis of one of the Asp-N peptides revealed that Arg180 is replaced by Trp. An essentially complete (99%) amino acid sequence of IX Nagoya was obtained by sequencing fragments derived from a lysyl endopeptidase digest in which no other substitutions in the catalytic triad or substrate binding site were found. We also found that IX Nagoya is activated by alpha-chymotrypsin or rat mast cell chymase by monitoring the rate of factor X activation using a fluorogenic peptide substrate in the presence of factor VIII, phospholipids, and Ca2+. These results indicate that the substitution of Arg180 by Trp impairs the cleavage by factor XIa required for activation of this zymogen and that the substitution causes hemophilia BM. 相似文献
24.
Nakayama Ishizue; Miyazawa Takeshige; Kobayashi Masatomo; Kamiya Yuji; Abe Hiroshi; Sakurai Akira 《Plant & cell physiology》1990,31(2):195-200
The effects of a novel plant growth regulator (PGR) prohexadionecalcium (BX-112; calcium 3,5-dioxo-4-propionylcyclohexanecarboxylate)on shoot elongation caused by exogenously applied GA1, GA3,GA4) GA19 and GA20 were investigated in rice (Oryza sativa L.cv. Nihonbare and cv. Tan-ginbozu) seedling test. Dependingon the dose, BX-112 reduced shoot elongation in both cultivarscaused by GA19 and GA20, but not by GA1. When a high dose ofBX-112 (e.g. 250 ng/plant and over) was applied with GA1, orGA4, shoot elongation was even promoted. This promotive effect,however, was not observed with GA3. These results suggest thatBX-112 inhibits gibberellin (GA) biosynthesis in the rice plantat the 3ß- and 2ß-hydroxylation of GAs,namely steps of activation and inactivation, respectively. (Received September 6, 1989; Accepted November 27, 1989) 相似文献
25.
Hohzoh Kiyohara Toshiro Watanabe Junko Imai Noboru Takizawa Takashi Hatta Kazutaka Nagao Akira Yamamoto 《Applied microbiology and biotechnology》1990,33(6):671-676
Summary To breed industrially useful strains of a slow-growing, red-pigment-producing strain ofMonascus anka, protoplasts ofM. anka MAK1 (arg) andAspergillus oryzae AOK1 (met, thr) were fused. A mixture of protoplasts prepared from mycelia ofM. anka MAK1 treated with 2% Usukizyme and ofA. oryzae AOK1 treated with 2% Usukizyme and 0.2% NovoZym 234 was incubated with 30% (w/v) polyethylene glycol no. 6000. Heterokaryon fusants complementing the auxotrophies of both mutants were isolated on minimal medium, but segregated into red (MAK1) and white (AOK1) sectors after being cultured on a complete medium. After irradiation with UV light, the fusants gave stable heterozygous diploids that formed long white hyphae. These diploids, which had twice as much DNA in the nucleus as their parents, grew more rapidly than the parent strain YZT1, and produced ethanol earlier than the parents. Production of amylase, protease, and kojic acid by the fusants was intermediate in amount between that of the two parents. 相似文献
26.
Hiroyuki Yamaguchi Hitoshi Miura Kazuoki Ohsumi Takako Osaki Haruhiko Taguchi Tomoko Yamamoto Tomoko Hanawa Sachio Ogata Shigeru Kamiya 《Microbiology and immunology》1996,40(1):77-80
To determine amino acid sequences of the epitopes recognized by monoclonal antibodies (mAbs) 3C8 and 5C3 directed against Yersinia enterocolitica heat-shock protein (HSP60), a dot blot analysis was perfomed using synthesized peptides of Y. enterocolitica HSP60 such as peptides p316-342, p327-359, p340-366, p316-326, p316-321, p319-323, and p321-326 which represent positions of amino acids in Y. enterocolitica HSP60. The dot blot analysis revealed that 5C3 mAb reacted with p316-342, p316-326 and p321-326, and 3C8 mAb p316-342 and p316-326. These results indicate that the epitopes recognized by the mAbs were associated with eleven amino acids, Asp Leu Gly Gln Ala Lys Arg Val Val Ile Asn, of p316-326. The sequence homology between p316-326 of Y. enterocolitica HSP60 and the rest of the HSP60 family suggests that the five amino acids of Lys, Arg, Val, Ile and Asn, which are highly conserved in the HSP60 family, might be related with the epitope recognized by 3C8. In contrast, it was also demonstrated that three amino acids of Leu, Gly and Val, which are not well conserved in the HSP60 family, might be related to the epitope recognized by 5C3. 相似文献
27.
Morphological and hybridization experiments were performed on Caloglossa leprieurii (Montagne) J. Agardh collected from Japan, Singapore and Australia in order to evaluate taxonomic characters of this species. Within C. leprieurii at least four mating groups were recognized from the Indo-Pacific region. These mating groups could be characterized by the blade width at the inter-node and the cell-row numbers on the opposite side derived from the first axial cell at the main axis, though these properties showed a certain variability even in the same plant under both field and culture conditions. The phylogenetic relationship and geographic distribution of the four mating groups are discussed. 相似文献
28.
Koichiro Yoshihara Motokatsu Tsuyuki Asako Itaya Yasuharu Tanaka Tomoya Kamiya 《Molecular and cellular biochemistry》1994,135(2):143-151
HL-60 cells transferred from serum-supplemented to serum-free culture medium initially bound to culture plate tightly and then released from the plate on increasing the culture time and resumed exponential growth after about 8 h lag. At the initial stage of the culture, the cells became extremely sensitive to 3-aminobenzamide, a potent inhibitor of poly (ADP-ribose) polymerase, and, at 1 mM, 80 to 90% of the cells were lysed within 20 h, whereas the inhibitor was totally ineffective on the cell growth in serum-supplemented medium at the concentration. Non-inhibitory analogs of the inhibitor were ineffective. Assay of poly(ADP-ribose) polymerase activity in permeable cells indicated that a transient activation of the enzyme occurred during the culture in serum-free medium (the maximum activation was observed at 8 h of the culture). The cells conditioned in serum-free medium for 24 h acquired significant resistancy to the inhibitor. A low concentration of fibronectin (5 to 10/ml) and a relatively high concentration of bovine serum albumin (0.5 to 1 mg/ml) effectively blocked the cell attachment to plate and also the 3-aminobenzamide-induced cell lysis. These results suggest that poly(ADP-ribose) polymerase is involved in a process essential for HL-60 cells to adapt to a serumdeprived growth condition. 相似文献
29.
In a colorless mutant of Chlorella kessleri, far-red light significantlyenhanced the K+ efflux. This effect was abolished by the K+channel-blocker tetraethylammonium acetate. Using cyanine dyeto monitor membrane potential, we deduced that the K+ effluxunder far-red light was probably accompanied by hyperpolarizationof the plasmalemma. (Received August 30, 1993; Accepted November 16, 1993) 相似文献
30.
Soh Chang-Ho; Kamiya Yuji; Yoshida Shigeo; Yamane Hisakazu; Takahashi Nobutaka 《Plant & cell physiology》1994,35(7):1037-1042
Oryzains, cysteine proteinases of rice seeds, are induced byGA3 in germinating rice seeds [Abe et al. (1987) Agric. Biol.Chem. 51: 1509]. The effects of GA1, GA3, GA4, GA9, and GA20on the production of oryzain and -amylase were investigatedin embryoless half- and whole-seeds of rice (cv. Nipponbare).When gibberellins (GAs) were incubated with embryoless half-seeds,GA1, GA3 and GA4 induced oryzain and -amylase, but GA9, andGA20 did not. GA9 and GAM induced oryzain and -amylase productionin whole seeds, but this production was inhibited by the simultaneousapplication of prohexadione, an inhibitor of 2ß- and3ß-hydroxylation of GAs. Prohexadione did not inhibitthe activities of oryzain and -amylase induced by GA1. Theseresults suggest that GAs possessing the 3ß-hydroxylgroup induce activities of oryzain and -amylase in rice seedsand that GA9 and GA20 have activity only after they are convertedmetabolically to active GAs, probably GA4 and GA1, respectively.GA1, was more active than GA4 in both half seeds and wholeseeds incubation. Oryzain and -amylase activities induced byGA4 were significantly inhibited in the presence of 104M prohexadione. This suggests that the conversion of GA1, toGA4 (13-hydroxylation) might be inhibited at a high dose ofprohexadione in whole seeds.
4Present address: Institute of Food Development, Kyung Hee University,Suwon 449-701, Korea 相似文献