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961.
962.
Tsutomu Yokomatsu Hiroshi Abe Mutsumi Sato Kenji Suemune Taro Kihara Shinji Soeda Hiroshi Shimeno Shiroshi Shibuya 《Bioorganic & medicinal chemistry》1998,6(12):2495-2505
A series of 1,1-difluoro-5-(1H-9-purinyl)-2-pentenylphosphonic acids, (E)-2a,b and (Z)-2a,b, as well as the related methano analogues (±)-3a,b and (±)-4a,b were prepared for evaluation of their PNP inhibitory activities. The cyclopopane ring and the hypoxanthine residue were found to increase the profile of inhibitory activity. The IC50 and Ki values of difluoro{(1R*,2S*)-2-[2-(6-oxo-6,9-dihydro-1H9-purinyl)ethyl]cyclopropyl}methylphosphonic acid (±)-3b toward PNP purified from Cellulomonas sp. were determined to be 70 nM and 8.8nM, respectively. 相似文献
963.
Complete genome structure of Gloeobacter violaceus PCC 7421, a cyanobacterium that lacks thylakoids. 总被引:5,自引:0,他引:5
Yasukazu Nakamura Takakazu Kaneko Shusei Sato Mamoru Mimuro Hideaki Miyashita Tohru Tsuchiya Shigemi Sasamoto Akiko Watanabe Kumiko Kawashima Yoshie Kishida Chiaki Kiyokawa Mitsuyo Kohara Midori Matsumoto Ai Matsuno Naomi Nakazaki Sayaka Shimpo Chie Takeuchi Manabu Yamada Satoshi Tabata 《DNA research》2003,10(4):137-145
964.
Manabu Hibino Taro Ohta Takane Isoda Kouji Nakayama Masaru Tanaka 《Ichthyological Research》2007,54(4):367-373
We collected eggs and larvae of the Japanese temperate bass, Lateolabrax japonicus, and present horizontal and temporal changes of distribution relative to development and growth during the species pelagic
life history in Ariake Bay. Sampling was conducted from the inner to central region (11 sampling stations) of Ariake Bay using
a plankton net (80 cm diameter, 0.5-mm mesh) from November 2000 to February 2001. Both eggs and larvae were collected most
abundantly in mid-December. The CPUE of eggs in the surface layer was higher than the middle layer, which is in contrast to
that at the larval stage. Most eggs were collected around the central and western regions of the bay. The distribution of
eggs shifted vertically to the middle layer with development. Yolk-sac larvae were collected in the central region of the
bay, and preflexion and flexion larvae were more abundantly collected in the inner region of the bay. The body length of larvae
around the inner bay was larger than in the central region. The pelagic life history can be summarized as follows: eggs are
distributed around the central region of the bay and eggs and larvae expand their distribution to the inner and shallower
waters with growth. We conclude that the shift of vertical distribution in pelagic stages and the hydrographic features of
the middle layer form one of the mechanisms enabling the inshore migration of L. japonicus. 相似文献
965.
966.
Neval Yilmaz Taro Yamada Peter Greimel Takayuki Uchihashi Toshio Ando Toshihide Kobayashi 《Biophysical journal》2013,105(6):1397-1405
Pore-forming toxins (PFTs) are soluble proteins that can oligomerize on the cell membrane and induce cell death by membrane insertion. PFT oligomers sometimes form hexagonal close-packed (hcp) structures on the membrane. Here, we show the assembling of the sphingomyelin (SM)-binding PFT, lysenin, into an hcp structure after oligomerization on SM/cholesterol membrane. This process was monitored by high-speed atomic force microscopy. Hcp assembly was driven by reorganization of lysenin oligomers such as association/dissociation and rapid diffusion along the membrane. Besides rapid association/dissociation of oligomers, the height change for some oligomers, possibly resulting from conformational changes in lysenin, could also be visualized. After the entire membrane surface was covered with a well-ordered oligomer lattice, the lysenin molecules were firmly bound on the membrane and the oligomers neither dissociated nor diffused. Our results reveal the dynamic nature of the oligomers of a lipid-binding toxin during the formation of an hcp structure. Visualization of this dynamic process is essential for the elucidation of the assembling mechanism of some PFTs that can form ordered structures on the membrane. 相似文献
967.
Most viruses move intracellularly to and from their sites of replication using microtubule-based mechanisms. In this study, we show that nucleocapsids of the baculovirus Autographa californica multiple nucleopolyhedrovirus undergo intracellular motility driven by actin polymerization. Motility requires the viral P78/83 capsid protein and the host Arp2/3 complex. Surprisingly, the virus directs two sequential and coordinated phases of actin-based motility. Immediately after cell entry, motility enables exploration of the cytoplasm and collision with the nuclear periphery, speeding nuclear entry and the initiation of viral gene expression. Nuclear entry itself requires transit through nuclear pore complexes. Later, after the onset of early gene expression, motility is required for accumulation of a subpopulation of nucleocapsids in the tips of actin-rich surface spikes. Temporal coordination of actin-based nuclear and surface translocation likely enables rapid transmission to neighboring cells during infection in insects and represents a distinctive evolutionary strategy for overcoming host defenses. 相似文献
968.
Yodai Takei Ryo Iizuka Taro Ueno Takashi Funatsu 《The Journal of biological chemistry》2012,287(49):41118-41125
The chaperonin, GroEL, is an essential molecular chaperone that mediates protein folding together with its cofactor, GroES, in Escherichia coli. It is widely believed that the two rings of GroEL alternate between the folding active state coupled to GroES binding during the reaction cycle. In other words, an asymmetric GroEL-GroES complex (the bullet-shaped complex) is formed throughout the cycle, whereas a symmetric GroEL-(GroES)2 complex (the football-shaped complex) is not formed. We have recently shown that the football-shaped complex coexists with the bullet-shaped complex during the reaction cycle. However, how protein folding proceeds in the football-shaped complex remains poorly understood. Here, we used GFP as a substrate to visualize protein folding in the football-shaped complex by single-molecule fluorescence techniques. We directly showed that GFP folding occurs in both rings of the football-shaped complex. Remarkably, the folding was a sequential two-step reaction, and the kinetics were in excellent agreement with those in the bullet-shaped complex. These results demonstrate that the same reactions take place independently in both rings of the football-shaped complex to facilitate protein folding. 相似文献
969.
970.
Giant vesicles (GVs) encapsulating colloidal particles by a specific volume fraction show a characteristic configuration under a hypertonic condition. Several flat faces were formed in GV membrane with orderly array of inner particles. GV shape changed from the spherical to the asymmetrical polyhedral configuration. This shape deformation was derived by entropic interaction between inner particles and GV membrane. Because a part of inner particles became to form an ordered phase in the region neighboring the GV membrane, free volume for the other part of particles increased. Giant vesicles encapsulating colloidal particles were useful for the model of “crowding effect” which is the entropic interaction in the cell. 相似文献