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991.
Effect of Materials Released from Myofibrils by CAF (Ca2+-activated Factor) on Z-Disk Reconstitution
Atsushi Suzuki Makoto Saito Hiroshi Sato Yoshinobu Nonami 《Bioscience, biotechnology, and biochemistry》2013,77(11):2111-2116
To investigate the constituents of Z-disk, reconstitution of Z-disk by incubating some proteins released from myofibrils by CAF(Ca2+-activated factor) with Z-disk-extracted fiber bundles was carried out and examined with electron microscope. The materials released from myofibrils by CAF have been bound in Z-disk region, and Z-disk extracted from myofibrils with a low ionic strength solution has been reconstituted. On the other hand, Z-disk removed from myofibrils by CAF has not been reconstituted by the same way. 相似文献
992.
Yoshikazu Izumi Kuninori Sato Yoshiki Tani Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(6):1335-1340
The 7-keto-8-aminopelargonic acid (KAPA) synthetase activities of cell-free extracts from various bacteria were investigated. The experiments on the substrate specificity of KAPA synthetase, using crude cell-free extracts from bacteria having high enzyme activity, showed that l-serine and pyruvic acid could replace l-alanine, but that, when the enzyme was partially purified, these compounds were not effective. Many kinds of amino acids such as l-cysteine, l-serine, d-alanine, glycine, d-histidine, and l-histidine, inhibited the enzyme activity. This inhibition was found to be competitive with l-alanine. Pyridoxal 5′-phosphate, which is a cofactor of the enzyme, also inhibited the enzyme activity at high concentrations. The repression of KAPA synthetase by biotin occurred in Bacillus subtilis and B. sphaericus but not in Micrococcus roseus and Pseudomonas fluorescens, even at a concentration of 1000 mµg per ml of biotin. 相似文献
993.
Data are presented to show the gas chromatographic identification of a total of 18 saturated aliphatic γ- and δ-lactones obtained from melted beef depot fat, namely, δ-C6, γ-C7, γ-C8, γ-C9, and a homologous series of γ- and δ-lactones of the even-carbon numbers C10 to C16 and of smaller amount of the odd-carbon numbers C11 to C15. These lactones were isolated by steam distillation and silicic acid adsorption chromatography, and identified through gas chromatography and infrared spectroscopy.Lactones obtained had a peach-like flavor, and it was suggested that lactones were important in heated beef fat as the flavor compounds. 相似文献
994.
The fractionation pattern of OMG0, ovomucin gel(B) in fresh egg white, by density gradient column electrophoresis showed two peaks. Each peak was shown to migrate as a single component, with a mobility of either the fast or slow moving component of ovomucin gel(B). Each peak was named as F-component and S-component.Carbohydrate and sulfate contents of F-component were much higher than these of S-component. The carbohydrate content of F-component and S-component was found to be about 50 and 15 percents of dry matter, respectively. Serine and threonine contents in F-component were much higher than those in S-component.The fractionation pattern of OMG20, ovomucin gel(B) in egg white stored for 20 days at 30°C, by density gradient electrophoresis showed only one peak which corresponded to S-component, and that of OMS20, ovomucin sol (B) in egg white stored for 20 days at 30°C, showed two peaks which corresponded to F- and S-component.Ability of F-component to interact with lysozyme was greater than that of S-component. 相似文献
995.
It is well known that axons of the adult mammalian central nervous system have a very limited ability to regenerate after injury. Therefore, the neurodegenerative process of glaucoma results in irreversible functional deficits, such as blindness. Brimonidine (BMD) is an alpha2-adrenergic receptor agonist that is used commonly to lower intraocular pressure in glaucoma. Although it has been suggested that BMD has neuroprotective effects, the underlying mechanism remains unknown. In this study, we explored the molecular mechanism underlying the neuroprotective effect of BMD in an optic nerve injury (ONI) model. BMD treatment promoted optic nerve regeneration by inducing Erk1/2 phosphorylation after ONI. In addition, an Erk1/2 antagonist suppressed BMD-mediated axonal regeneration. A gene expression analysis revealed that the expression of the neurotrophin receptor gene p75 was increased and that the expression of the tropomyosin receptor kinase B (TrkB) gene was decreased after ONI. BMD treatment abrogated the changes in the expression of these genes. These results indicate that BMD promotes optic nerve regeneration via the activation of Erk1/2. 相似文献
996.
Glutathione maintenance is crucial for survival of melanocytes after exposure to rhododendrol 下载免费PDF全文
Masatoshi Kondo Keigo Kawabata Kohji Sato Sayuri Yamaguchi Akira Hachiya Yoshito Takahashi Shintaro Inoue 《Pigment cell & melanoma research》2016,29(5):541-549
Rhododendrol is a phenolic compound that shows a tyrosinase‐dependent toxicity for melanocytes and occasionally induces a vitiligo‐like skin depigmentation. The post‐tyrosinase mechanisms determining melanocyte death or survival, however, are far from clear. Here, we find that rhododendrol treatment leads to a reduction in the levels of cellular glutathione but also induces a cellular antioxidant response that eventually increases glutathione levels. We further find that rhododendrol toxicity is enhanced when glutathione levels are experimentally reduced and alleviated when glutathione levels are increased. Hence, it appears that the size of the preexisting glutathione pool along with the capacity to supply glutathione via the antioxidant response determines whether melanocytes survive or die after rhododendrol exposure. It is conceivable, therefore, that rhododendrol‐induced leukoderma depends on the capacity to maintain appropriate glutathione levels and that enhancement of glutathione levels may preserve a patient's melanocytes and potentially help in repigmentation. 相似文献
997.
998.
Murakami Shinsuke Nakatani Jun Nakajima Kenichi Amasawa Eri Ii Ryota Hayashi Kiyotada Yoshikawa Naoki Daigo Ichiro Kishita Yusuke Ihara Tomohiko Shobatake Koichi Kudoh Yuki Motoshita Masaharu Kanemoto Keiichiro Hara Minako Kashiwagi Aiichiro Hashimoto Seiji Shigetomi Yosuke Kanzaki Masayuki Kikuchi Yasunori Ohno Hajime Fukushima Yasuhiro 《The International Journal of Life Cycle Assessment》2019,24(8):1544-1552
The International Journal of Life Cycle Assessment - 相似文献
999.
1000.
Lewis acid-promoted reactions of peracetylated sugars (glucose, galactose, maltose, lactose) with omega-bromo-1-alkanols (C(8), C(12)) were investigated. ZnCl(2) was found to promote the 1,2-trans-glycosylation of the alcohols in toluene at about 60 degrees C in a stereocontrolled manner with better yields than commonly employed promoters such as SnCl(4). The omega-bromoalkyl acetylated glycosides were readily converted to omega-mercaptoalkyl glycosides, which are useful for the preparation of glycoclusters. 相似文献