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51.
Differences between Lactobacillus casei subsp. casei 2206 and Citrate-Positive Lactococcus lactis subsp. lactis 3022 in the Characteristics of Diacetyl Production 下载免费PDF全文
Lactobacillus casei subsp. casei 2206 exhibited much lower levels of diacetyl reductase activity than Citr+Lactococcus lactis subsp. lactis 3022 but two-, three-, and more than eightfold-higher levels of diacetyl synthase, lactate dehydrogenase, and NADH oxidase activities, respectively. A requirement for metal ions by the diacetyl synthases in both species was observed. The extracts of strain 2206 but not strain 3022 produced more diacetyl from pyruvate when the reaction for diacetyl synthase was aerated than when it was conducted statically. 相似文献
52.
Hajime Tokuda Tsutomu Unemoto 《Biochemical and biophysical research communications》1981,102(1):265-271
The membrane potential generated at pH 8.5 by K+-depleted and Na+-loaded is not collapsed by proton conductors which, instead, induce the accumulation of protons in equilibrium with the membrane potential. The generation of such a membrane potential and the accumulation of protons are specific to Na+-loaded cells at alkaline pH and are dependent on respiration. Extrusion of Na+ at pH 8.5 occurs in the presence of proton conductors unless respiration is inhibited while it is abolished by proton conductors at acidic pH. The uptake of α-aminoisobutyric acid, which is driven by the Na+-electrochemical gradient, is observed even in the presence of proton conductors at pH 8.5 but not at acidic pH. We conclude that a respiration-dependent primary electrogenic Na+ extrusion system is functioning at alkaline pH to generate the proton conductor-insensitive membrane potential and Na+ chemical gradient. 相似文献
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3′,4′-Dideoxykanamycin B, the kanamycin B derivative that is active against resistant bacteria, was prepared from kanamycin B viaN-tosylation, 3′,4′-O-sulphonylation, 3′,4′-unsaturation, and hydrogenation. The unsaturated intermediate was obtained from the 3′,4′-di-O-sulphonyl derivatives by the action of sodium iodide in N,N-dimethylformamide; if zinc dust was added in this reaction, aziridine derivatives were formed, Removal of the tosyl group was successfully performed by using sodium in ammonia-ethylamine. 相似文献
55.
The antibiotic cordycepin (3'-deoxyadenosine), a known specificinhibitor of nucleic acid synthesis and polyadenylation of RNA,remarkably retarded decrease in the chlorophyll and proteincontents of senescing tobacco leaf disks. The effectivenessof cordycepin, at its optimum concentration (ca. 4 x 105M), was 53% as effective as a cytokinin, benzyladenine at 106M. Adenosine and 2'-deoxyadenosine had no anti-senescence action. (Received May 29, 1975; ) 相似文献
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Sakiyama Tomoki Morimoto Junko Matsubayashi Jun Furukawa Yasuto Kondo Mami Tsuruga Hifumi Mano Tsutomu Nakamura Futoshi 《Landscape and Ecological Engineering》2021,17(3):351-362
Landscape and Ecological Engineering - Investigating factors underlying human-wildlife conflicts in agricultural landscapes is important for both preventing crop damage and wildlife conservation.... 相似文献
58.
Arakawa Tsutomu Tokunaga Masao Kita Yoshiko Niikura Takako Baker Richard W. Reimer Janice M. Leschziner Andres E. 《The protein journal》2021,40(6):867-875
The Protein Journal - Difference circular dichroism (CD) spectroscopy was used here to characterize changes in structure of flexible peptides upon altering their environments. Environmental changes... 相似文献
59.
Phylogeography of Fischer’s blue,Tongeia fischeri,in Japan: Evidence for introgressive hybridization
Ekgachai Jeratthitikul Takehiro Hara Masaya Yago Tateo Itoh Min Wang Shin-ichi Usami Tsutomu Hikida 《Molecular phylogenetics and evolution》2013,66(1):316-326
The widespread lycaenid butterfly Tongeia fischeri is distributed from eastern Europe to northeastern Asia and represented by three geographically isolated populations in Japan. In order to clarify the phylogeographic history of the species, we used sequences of three mitochondrial (COI, Cyt b and ND5) and two nuclear (Rpl5 and Ldh) genes of 207 individuals collected from 55 sites throughout Japan and five sites on the Asian continent. Phylogenetic trees and the median-joining network revealed six evolutionary mitochondrial haplotype clades, which corresponded to the geographic distribution of the species. Common ancestors of Japanese T. fischeri might have come to Japan during the mid-Pleistocene by multiple dispersals of continental populations, probably via a land bridge or narrow channel between western Japan and the Korean Peninsula. The geographical patterns of variation of mitochondrial and nuclear markers are discordant in northeastern Kyushu, possibly as a result of introgressive hybridization during the ancient contact between the Kyushu and Shikoku populations in the last glacial maximum. The phylogeographic pattern of T. fischeri in Japan are probably related to the geological history, Pleistocene climatic oscillations and distribution of the host plant. 相似文献
60.
Hiroto Ueba Masashi Shiomi Michael Brines Michael Yamin Tsutomu Kobayashi Junya Ako Shin-ichi Momomura Anthony Cerami Masanobu Kawakami 《Molecular medicine (Cambridge, Mass.)》2013,19(1):195-202
Erythropoietin (EPO), a type I cytokine originally identified for its critical role in hematopoiesis, has been shown to have nonhematopoietic, tissue-protective effects, including suppression of atherosclerosis. However, prothrombotic effects of EPO hinder its potential clinical use in nonanemic patients. In the present study, we investigated the antiatherosclerotic effects of helix B surface peptide (HBSP), a nonerythropoietic, tissue-protective compound derived from EPO, by using human umbilical vein endothelial cells (HUVECs) and human monocytic THP-1 cells in vitro and Watanabe heritable hyperlipidemic spontaneous myocardial infarction (WHHLMI) rabbits in vivo. In HUVECs, HBSP inhibited apoptosis (≈70%) induced by C-reactive protein (CRP), a direct mediator of atherosclerosis. By using a small interfering RNA approach, Akt was shown to be a key molecule in HBSP-mediated prevention of apoptosis. HBSP also attenuated CRP-induced production of tumor necrosis factor (TNF)-α and matrix metalloproteinase-9 in THP-1 cells. In the WHHLMI rabbit, HBSP significantly suppressed progression of coronary atherosclerotic lesions as assessed by mean cross-sectional stenosis (HBSP 21.3 ± 2.2% versus control peptide 38.0 ± 2.7%) and inhibited coronary artery endothelial cell apoptosis with increased activation of Akt. Furthermore, TNF-α expression and the number of M1 macrophages and M1/M2 macrophage ratio in coronary atherosclerotic lesions were markedly reduced in HBSP-treated animals. In conclusion, these data demonstrate that HBSP suppresses coronary atherosclerosis, in part by inhibiting endothelial cell apoptosis through activation of Akt and in association with decreased TNF-α production and modified macrophage polarization in coronary atherosclerotic lesions. Because HBSP does not have the prothrombotic effects of EPO, our study may provide a novel therapeutic strategy that prevents progression of coronary artery disease. 相似文献