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71.
A novel small protein of Bacillus subtilis involved in spore germination and spore coat assembly 总被引:1,自引:0,他引:1
Kodama T Matsubayashi T Yanagihara T Komoto H Ara K Ozaki K Kuwana R Imamura D Takamatsu H Watabe K Sekiguchi J 《Bioscience, biotechnology, and biochemistry》2011,75(6):1119-1128
Two small genes named sscA (previously yhzE) and orf-62, located in the prsA-yhaK intergenic region of the Bacillus subtilis genome, were transcribed by SigK and GerE in the mother cells during the later stages of sporulation. The SscA-FLAG fusion protein was produced from T(5) of sporulation and incorporated into mature spores. sscA mutant spores exhibited poor germination, and Tricine-SDS-PAGE analysis showed that the coat protein profile of the mutant differed from that of the wild type. Bands corresponding to proteins at 59, 36, 5, and 3 kDa were reduced in the sscA null mutant. Western blot analysis of anti-CotB and anti-CotG antibodies showed reductions of the proteins at 59 kDa and 36 kDa in the sscA mutant spores. These proteins correspond to CotB and CotG. By immunoblot analysis of an anti-CotH antibody, we also observed that CotH was markedly reduced in the sscA mutant spores. It appears that SscA is a novel spore protein involved in the assembly of several components of the spore coat, including CotB, CotG, and CotH, and is associated with spore germination. 相似文献
72.
Baker DL Fujiwara Y Pigg KR Tsukahara R Kobayashi S Murofushi H Uchiyama A Murakami-Murofushi K Koh E Bandle RW Byun HS Bittman R Fan D Murph M Mills GB Tigyi G 《The Journal of biological chemistry》2006,281(32):22786-22793
Autotaxin (ATX, nucleotide pyrophosphate/phosphodiesterase-2) is an autocrine motility factor initially characterized from A2058 melanoma cell-conditioned medium. ATX is known to contribute to cancer cell survival, growth, and invasion. Recently ATX was shown to be responsible for the lysophospholipase D activity that generates lysophosphatidic acid (LPA). Production of LPA is sufficient to explain the effects of ATX on tumor cells. Cyclic phosphatidic acid (cPA) is a naturally occurring analog of LPA in which the sn-2 hydroxy group forms a 5-membered ring with the sn-3 phosphate. Cellular responses to cPA generally oppose those of LPA despite activation of apparently overlapping receptor populations, suggesting that cPA also activates cellular targets distinct from LPA receptors. cPA has previously been shown to inhibit tumor cell invasion in vitro and cancer cell metastasis in vivo. However, the mechanism governing this effect remains unresolved. Here we show that 3-carba analogs of cPA lack significant agonist activity at LPA receptors yet are potent inhibitors of ATX activity, LPA production, and A2058 melanoma cell invasion in vitro and B16F10 melanoma cell metastasis in vivo. 相似文献
73.
Masaru Ohsaku Hiromu Murata Akira Imamura 《International journal of biological macromolecules》1982,4(2):103-106
Goniomers of single-stranded poly(dl-alanine) helices were treated by the semiempircal CNDO/2 MO procedure. The αR and forms were also calculated. From the calculated total energies and partitioned energies we discuss the conformational stablity of goniomers of poly(dl-alanines). The conformational stability of the α and π forms is also compared. 相似文献
74.
Free radical species in animals have been measured by X-band ESR spectrometric method on a block of organs or a portion of homogenized samples. However, a nondestructive in vivo ESR measurement has been realized by using a recently developed L-band ESR spectrometry. With this L-band ESR method, we measured ESR spectra in animals, who received stable nitroxide radicals. L-band ESR spectra were observed at the upper abdomen of mice as well as at the heads of mice and rats at various ages immediately after the intravenous injections of nitroxide radicals such as 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (4-hydroxy-TEMPO) and 3-carbamoyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl (3-carbamoyl-PROXYL), in which ESR measurements of the radicals were performed noninvasively at the real time. On the basis of the observed time-dependent free radical clearance curves, the following important results were obtained: (1) Free radical clearances were able to analyze by the pharmacokinetic method. (2) The radicals at the head of mice, given 4-hydroxy-TEMPO, were determined quantitatively by a new analytical method using L-band ESR for the first time. (3) The elimination of the radical was found to be saturated in mice. (4) The clearance rate constant of 4-hydroxy-TEMPO detected at the head of mice was decreased in dose- and age-dependent manners. While, no age-dependent clearance rate constant of 4-hydroxy-TEMPO was observed at the upper abdomen of mice. (5) Ratios of the amount of the detected radicals to that of the administered radicals were decreased age-dependently, but they were independent of the dose of the radicals, suggesting the age-dependent decrease of distribution capacity ratio of the radical at the head of animals. (6) Clearance rate constants of 4-hydroxy-TEMPO and 3-carbamoyl-PROXYL, that were estimated by X- and L-band ESR for the collected blood of mice and rats, were found to be remarkably smaller than those in whole living animals observed by in vivo L-band ESR method. The results suggest that the clearance of the nitroxide radical is relevant to the alteration of the radical in animals following the change of organ distribution and metabolism. (7) Both the radical and its corresponding hydroxylamine, which is the reduced form of the radical, were detectable by X-band ESR method in the collected urine of mice and rats without and with an oxidizing agent, respectively.
On the basis of the results on L-band ESR spectrometry, the first quantitative pharmacokinetic analysis of stable spin probes in animals is proposed. 相似文献
On the basis of the results on L-band ESR spectrometry, the first quantitative pharmacokinetic analysis of stable spin probes in animals is proposed. 相似文献
75.
Zen-ichiro Hamauzu Daizo Yonezawa Hiromu Shimomura 《Bioscience, biotechnology, and biochemistry》2013,77(4):448-451
Albumin preparations from four kinds of wheat flour (Durum, Manitoba No. 2, Western White and Norin No. 26) were analyzed by Immunoelectrophoresis. Seven to eleven components were detected for each preparation. They were classified and designated on the basis of the electrophoretic mobility (R) and the character of precipitin lines formed by antigen-antibody reactions. 相似文献
76.
Shuji Kitagawa Hiroko Fujisawa Fujio Kametani Hiromu Sakurai 《Free radical research》1992,15(6):319-324
Generation of active oxygen species by bovine blood platelets was examined by the electron spin resonance (ESR) spin trapping technique with 5,5-dimethyl-l-pyroline-l-oxide (DMPO). The hydroxyl spin-trapped adduct 5,5-dimethyl-2-hydroxy-l-pyrolidinyloxy (DMPO-OH) was formed in the presence of platelets, indicating the generation of hydroxyl radicals (· OH) by the platelets. Generation of · OH was observed even with platelets in the resting state, but was markedly enhanced when the platelets were activated with stimulants. Stronger stimulants such as the calcium ionophore ionomycin, induced greater radical gener-ation than the weaker stimulant ADP. When the platelets were stimulated by thrombin, generation of · OH was greatest after l.5 min, and depended on the dose of the stimulant. It was inhibited by inhibitors of platelet activation such as forskolin and phenolic antioxidants. 相似文献
77.
Koji Takechi Hideyuki Tamura Kiyoshi Yamaoka Hiromu Sakurat 《Free radical research》1997,26(6):483-496
In pharmacokinetic studies, a variety of analytical method including radioisotopic detection and HPLC (high performance liquid chromatography) has been used. In the present investigation, we developed in vivo BCM (Blood Circulation Monitoring)-ESR method, which is a new technique with a conventional X-band ESR spectrometer for observing stable free radicals in the circulating blood of living rats under anaesthesia. Both 5-(PROXYL derivatives) and 6-(TEMPO derivatives) membered nitroxide spin probes with various types of substituent functional group were used. After physicochemical properties of the spin probes such as hyperfine coupling constant (A-value), g-value and partition coefficient as well as chemical stability of the compounds in the fresh blood were obtained, the in vivo BCM-ESR method was performed in normal rats. Several pharmacokinetic parameters such as half-life of the probes, distribution volume, total body clearance and mean residence time were obtained and discussed in terms of their chemical structures. In addition, clearance of a spin probe was related to the urine concentration. The BCM-ESR method was found to be very useful to observe free radicals at the real time. By time-dependent ESR signal decay of spin probes, pharmacokinetic parameters were obtained. 相似文献
78.
Yutaka Narisawa Tetsuhito Kojima Atsushi Iriki Jiko Masaki Hiromu Kohda 《Mycopathologia》1989,106(2):113-119
The histologic variety and transformation in cutaneous cryptococcosis with acute lymphocytic leukemia before antifungal treatment and after the start of treatment were studied by the light and electron microscopic examinations. The initial cutaneous lesions before treatment revealed gelatinous tissue reactions, and Cryptococcus neoformans (serotype A) were isolated from the skin biopsy specimen and blood. However, later recurrent cutaneous lesions receiving antifungal treatment revealed suppurative granulomatous tissue reactions, and fungal cultures of the skin biopsy specimen changed to negative even though numerous yeasts stained with PAS were observed in skin lesions. Moreover, in the later lesion a few giant cells contained asteroid bodies without central spores. Ultrastructure of the later cutaneous lesions is presented. 相似文献
79.
80.
Gen Matsumoto Michinori Ichikawa Akira Tasaki Hiromu Murofushi Hikoichi Sakai 《The Journal of membrane biology》1983,77(2):77-91
Summary Effects of the reagents suppressing or supporting axoplasmic microtubule assembly were studied on the Na ionic current of squid giant axons by perfusing the axon internally with the solution containing the reagent. Among the reagents suppressing the assembly, colchicine, vinblastine, podophyllotoxin, sulfhydryl reagents such as DTNB and NEM, and chaotropic anions such as iodide and bromide, were examined. These reagents reduced maximum Na conductance and shifted the voltage dependence of steady-state Na activation in a depolarizing direction along the voltage axis. They also made the voltage dependence less steep, but did not affect sodium inactivation appreciably. Effects on Na ionic current of reagents which support microtubule assembly (Taxol, DMSO, D2O and temperature) were opposite the effects of those agents suppressing assembly. At the same time, we demonstrated that after Na currents were partially reduced, they could be restored by internally perfusing the axon with a solution containing microtubule proteins, 260K proteins and cAMP under conditions favorable for microtubule assembly. For full restoration, it was found that the following conditions were necessary: (1) The microenvironment within the axon is suitable for microtubule assembly. (2) Tubulins incorporated into microtubules are fully tyrosinated at their C-termini. (3) A peripheral protein having a molecular weight of 260,000 daltons (260K protein) is indispensable. These results suggest that axoplasmic microtubules and 260K proteins in the structure underlying the axolemma play a role in generating Na currents in squid giant axons. 相似文献