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991.
Hiroyuki Gatanaga Yasuhiro Suzuki Hsinyi Tsang Kazuhisa Yoshimura Mark F Kavlick Kunio Nagashima Robert J Gorelick Sek Mardy Chun Tang Michael F Summers Hiroaki Mitsuya 《The Journal of biological chemistry》2002,277(8):5952-5961
Amino acid substitutions in human immunodeficiency virus type 1 (HIV-1) Gag cleavage sites have been identified in HIV-1 isolated from patients with AIDS failing chemotherapy containing protease inhibitors (PIs). However, a number of highly PI-resistant HIV-1 variants lack cleavage site amino acid substitutions. In this study we identified multiple novel amino acid substitutions including L75R, H219Q, V390D/V390A, R409K, and E468K in the Gag protein at non-cleavage sites in common among HIV-1 variants selected against the following four PIs: amprenavir, JE-2147, KNI-272, and UIC-94003. Analyses of replication profiles of various mutant clones including competitive HIV-1 replication assays demonstrated that these mutations were indispensable for HIV-1 replication in the presence of PIs. When some of these mutations were reverted to wild type amino acids, such HIV-1 clones failed to replicate. However, virtually the same Gag cleavage pattern was seen, indicating that the mutations affected Gag protein functions but not their cleavage sensitivity to protease. These data strongly suggest that non-cleavage site amino acid substitutions in the Gag protein recover the reduced replicative fitness of HIV-1 caused by mutations in the viral protease and may open a new avenue for designing PIs that resist the emergence of PI-resistant HIV-1. 相似文献
992.
α-α′-Dipyridyl or Ortho-Phenanthroline Stimulation of the Soluble Reduced Nicotinamide Adenine Dinucleotide Oxidase from Bacillus subtilis Spores and Dipicolinic Acid Inhibition of the Stimulated Enzyme 下载免费PDF全文
Kunio Tochikubo 《Journal of bacteriology》1974,117(3):1017-1022
Soluble reduced nicotinamide adenine dinucleotide oxidase activity in extracts of Bacillus subtilis spores was stimulated by the addition of not only flavine mononucleotide (FMN) or flavine adenine dinucleotide (FAD) but also alpha-alpha'-dipyridyl or o-phenanthroline. These chelating agents showed stronger effect on the enzyme from spores than on that from vegetative cells. Activity stimulated by alpha-alpha'-dipyridyl or o-phenanthroline was inhibited by atabrine or dipicolinic acid, whereas FMN or FAD stimulation was inhibited only by atabrine. 相似文献
993.
Sawao Murao Motoo Arai Kunio Nakahara Masami Tsuchiya 《Bioscience, biotechnology, and biochemistry》2013,77(11):2041-2043
A tissue-type transglutaminase (TGase) was purified from liver tissue of the red sea bream, Pagrus major, by ion-exchange chromatography and heparin-Sepharose affinity chromatography. Its activity was assessed using a fluorometric assay to measure the incorporation of monodansylcadaverine into N,N′-dimethyl casein. The molecular mass of purified TGase was estimated to be 78kDa by SDS–polyacrylamide gel electrophoresis. The enzyme required Ca2+ to express its activity, although 10 mM Sr2+ also activated the enzyme fully. TGase activity was maximal at pH 9.0–9.5, and the enzyme was strongly inhibited by sulfhydryl reagents. The purified enzyme catalyzed the cross-linking of myosin heavy chain obtained from Alaska pollack, resulting in gelation of an actomyosin solution. The partial amino acid sequence of this fish TGase showed divisionally significant similarity to TGase from guinea pig liver. 相似文献
994.
Suzuki H Hirano Y Kimura Y Takaichi S Kobayashi M Miki K Wang ZY 《Biochimica et biophysica acta》2007,1767(8):1057-1063
A light-harvesting-reaction center (LH1-RC) core complex has been highly purified from a thermophilic purple sulfur bacterium, Thermochromatium tepidum. The bacteriochlorophyll (BChl) a molecules in the LH1 exhibit a Q(y) transition at 914 nm, more than 25 nm red-shift from those of its mesophilic counterparts. The LH1-RC complex was isolated in a monomeric form as confirmed by sucrose density gradient centrifugation, blue native PAGE and size-exclusion chromatography. Four subunits (L, M, H and a tetraheme cytochrome) in RC and two polypeptides (alpha and beta) in LH1 were identified. Spirilloxanthin was determined to be the predominant carotenoid in the core complex. The purified core complex was highly stable, no significant change in the LH1 Q(y) transition was observed over 10 days of incubation at room temperature in dark. Circular dichroism spectrum of the LH1 complex was characterized by low intensity and nonconservative spectral shape, implying a high symmetry of the large LH1 ring and interaction between the BChl a and carotenoid molecules. A dimeric feature of the BChl a molecules in LH1 was revealed by magnetic circular dichroism spectrum. Crystals of the core complex were obtained which diffracted X-rays to about 10 A. 相似文献
995.
Kunio Sasaki 《Ichthyological Research》1992,39(3):191-199
Two new species of the sciaenid genusJohnius (Johnius) are described:J. trewavasae from Taiwan, Hong Kong, and Singapore, differs from all other congeners in having 24–27 dorsal soft rays, 5–6 scales above
and 7–10 scales below the lateral line, 6–8 obtuse lower gill rakers, the last pleural rib on the 11th vertebra, and a shorter
lower jaw (33.8–38.4% HL);J. latifrons from Thailand and Java is characterized by 25–29 dorsal soft rays, 7–9 scales above and 11–14 scales below the lateral line,
7–9 obtuse lower gill rakers, a wide interorbital width (26.1–30.6% HL), a small eye (16.7–26.4% HL), and a short, second
anal spine (25.9–37.1% HL). Two related species,J. heterolepis Bleeker from “Suriname” andJ. cantori Bleeker from Malaya, are resurrected as valid West Pacific species of Johnius (Johnius). 相似文献
996.
997.
Taihei Miyakawa Shoichi Katsuragi Kunio Araki Tetsuo Hashimura Takemi Kimura Ryoko Kuramoto 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,57(1):267-273
The ultrastructure of neurofibrillary tangles (NFT) was examined by electron microscopy. The fibrils of NFT seemed to consists
of about eight protofilaments consisting of globular subunits; these protofilaments were helically wound in a longitudinal
direction. The fibrils of NFT had hollow structures at their centers surrounded by the eight globular subunits. The subunits
were tighty connected in the narrow parts of the fibril, but more loosely connected in the wider parts. From these findings,
it seemed that the fibrils of NFT consist of a twisted tubule having periodical `constrictions and is made up of eight helically
wound protofilaments, forming globular subunits. 相似文献
998.
K Ohmiya K Nagashima T Kajino E Goto A Tsukada S Shimizu 《Applied and environmental microbiology》1988,54(6):1511-1515
The gene for cellulase from Ruminococcus albus F-40 was cloned in Escherichia coli HB101 with pBR322. A 3.4-kilobase-pair HindIII fragment encoding cellulase hybridized with the chromosomal DNA of R. albus. The Ouchterlony double-fusion test gave a single precipitation line between the cloned enzyme and the cellulase from R. albus. The size of the cloned fragment was reduced by using HindIII and EcoRI. The resulting active fragment had a size of 1.9 kilobase pairs; and the restriction sites EcoRI, BamHI, PvuII, EcoRI, PvuII, and HindIII, in that order, were ligated into pUC19 at the EcoRI and HindIII sites (pURA1). Cellulase production by E. coli JM103(pURA1) in Luria-Bertani broth was remarkably enhanced, up to approximately 80 times, by controlling the pH at 6.5 and by reducing the concentration of NaCl in the broth to 80 mM. 相似文献
999.
1000.
Kunio Mizutari Masato Fujioka Makoto Hosoya Naomi Bramhall Hirotaka James Okano Hideyuki Okano Albert S.B. Edge 《Neuron》2013,77(1):58-69
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