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181.
Takuro Nunoura Yoshihiro Takaki Hiromi Kazama Jungo Kakuta Shigeru Shimamura Hiroko Makita Miho Hirai Masayuki Miyazaki Ken Takai 《PloS one》2014,9(8)
Strain Hiromi 1, a sulfur-oxidizing gammaproteobacterium was isolated from a hydrothermal vent chimney in the Okinawa Trough and represents a novel genus that may include a phylogenetic group found as endosymbionts of deep-sea gastropods. The SSU rRNA gene sequence similarity between strain Hiromi 1 and the gastropod endosymbionts was approximately 97%. The strain was shown to grow both chemolithoautotrophically and chemolithoheterotrophically with an energy metabolism of sulfur oxidation and O2 or nitrate reduction. Under chemolithoheterotrophic growth conditions, the strain utilized organic acids and proteinaceous compounds as the carbon and/or nitrogen sources but not the energy source. Various sugars did not support growth as a sole carbon source. The observation of chemolithoheterotrophy in this strain is in line with metagenomic analyses of endosymbionts suggesting the occurrence of chemolithoheterotrophy in gammaproteobacterial symbionts. Chemolithoheterotrophy and the presence of homologous genes for virulence- and quorum sensing-related functions suggest that the sulfur-oxidizing chomolithotrophic microbes seek animal bodies and microbial biofilm formation to obtain supplemental organic carbons in hydrothermal ecosystems. 相似文献
182.
Hirai Nobuhiro; Yamamuro Munehiro; Koshimizu Koichi; Shinozaki Masateru; Takimoto Atsushi 《Plant & cell physiology》1994,35(4):691-695
Extracts from the cotyledons of seedlings of Pharbitis nil strainViolet cultured at low temperature, which inducestheir flowering even in continuous light, with or without precedentexposure to high-intensity light, which shortens the periodof low temperature required for flowering, were analyzed byHPLC for substances correlating with the flower-inducing process.The content of two phenylpropanoids were found to increase duringthe low-temperature, and were identified as 3-O-feruloylquinicacid and dehydrodiconiferyl alcohol-13-O-ß-D-glucoside.The increase was more rapid in the cotyledons exposed to high-intensitylight before the low-temperature. This suggests that the accumulationof these compounds is correlated to the promotive effect ofhigh-intensity light on the flower-induction by low temperature. (Received March 7, 1994; Accepted April 2, 1994) 相似文献
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A recombinant Bacillus subtilis MI113(pC115), carrying a gene responsible for the production of surfactin and iturin A cloned from B. subtilis RB14C, produced new surfactin variants, in addition to the already reported surfactin, when MI113(pC115) was cultured in
solid-state fermentation of soybean curd residue (okara) as a substrate. All variants isolated by HPLC were characterized.
Received: 18 December 1996 / Received revision: 20 February 1997 / Accepted: 28 February 1997 相似文献
187.
Yumi Nakayama Weiping Su Kei-Ichi Katayama Hiroyuki Nakayama Kunio Doi 《Experimental Animals》2004,53(2):165-169
Pregnant mice of the BALB/c CrSlc strain were experimentally infected with the D variant of encephalomyocarditis virus (EMC-D, 5 x 10(2) PFU/head) on three different gestational days (GD). Mice were intraperitoneally inoculated with EMC-D on 11, 13 and 15 GD and sacrificed 3 days post inoculation. There was no significant difference in the fetal mortality among all inoculation groups. Placenta showed higher virus titer than fetus and dam's serum in all inoculation groups, and the virus titer of the fetus was lowest in the 15GD group. Histopathological changes and signals of viral RNAs detected by in situ hybridization were observed almost restricted to the spongiotrophoblast layer of the placenta in all inoculation groups, and the signals were strongest in the 11GD group. In the fetus of the11GD group, signals of viral RNAs were also seen in myocardium and hepatocytes. Ultrastructurally, intracytoplasmic aggregations of virus-like particles in crystalline array were observed in trophoblast cells and giant cells in the spongiotrophoblast layer in all inoculation groups. 相似文献
188.
M Ihara M Mitao H Yamasaki T Kodama T Murakami G Hirai T Sugiyama N Toyoda 《Hormones et métabolisme》2002,34(6):338-340
The effect of twin gestation on carbohydrate metabolism was evaluated using a 75 g oral glucose tolerance test (75 g OGTT). A 75 g OGTT was performed in 63 twin gestations and 3 791 singleton gestations during the third trimester. Plasma glucose concentrations were measured in the pregnant women under fasting conditions as well as 30 min, 1 h, and 2 h after ingestion of glucose (75 g oral load), and serum insulin concentrations were measured in fasting and 30 min post-ingestion samples. Women with twin gestations showed significantly lower plasma glucose concentrations during fasting and 30 min after the glucose load in the samples taken than those with singleton gestations. No significant difference in serum glucose concentrations was found in the other specimens. There were no cases of gestational diabetes mellitus in our study. Although women with twin gestations demonstrated lower plasma glucose concentrations than women with singleton gestations, the difference observed was subtle. We could not find any significant differences in these plasma glucose values as used to define a pathologic OGTT between twin and singleton pregnancies, with the exception of the fasting value. 相似文献
189.
Tetsuya Tanaka Shin Murakami Haruto Kumura Ikuo Igarashi Kei-Ichi Shimazaki 《Biochimie et biologie cellulaire》2006,84(5):774-779
Toxoplasma gondii is an obligatory intracellular parasitic protozoan transmitted via the ingestion of raw, infected meat that causes congenital infections. In a cell-free environment, virulent Toxoplasma was strikingly resistant to H2O2. The activity of H2O2 or H2O2 generated by glucose-glucose oxidase against the resistant tachyzoite stage of pathogenic T. gondii was enhanced by adding KI and bovine lactoperoxidase (bLPO), referred to here as the bLPO system. Replacing bLPO (heme content, 90%) with recombinant bLPO (heme content, 6%) did not enhance the parasiticidal activity with KI and H2O2. These results indicated that heme contributed to the enzyme activity and resulted in the killing of tachyzoites of T. gondii. Tachyzoites treated with the bLPO system also lost the ability to penetrate the mouse fibroblast cell line (NIH/3T3), and could be killed intracellularly after exposure by bLPO to a mouse macrophage cell line (J774A.1). These findings suggested that toxicity was mediated through small amounts of H2O2 generated by phagocytic events in naive macrophages, and by the peroxidative activity of bLPO. Our observations suggest that the bLPO system could help prevent the development of Toxoplasmosis in humans after ingesting raw, infected meat. 相似文献
190.
Pudjiatmoko Hideto Fukushi Yoshitsugu Ochiai Tsuyoshi Yamaguchi Katsuya Hirai 《Microbiology and immunology》1998,42(1):61-63
The in vitro susceptibility of Chlamydia pecorum to two macrolides (clarithromycin and erythromycin), two tetracyclines (doxycycline and minocycline), two quinolones (ofloxacin and ciprofloxacin) and one β-lactam (ampicillin) was determined. The MICs were 0.004 to 0.008 μg/ml for clarithromycin, 0.008 to 0.031 μg/ml for doxycycline and minocycline, 0.063 to 0.125 μg/ml for erythromycin, 0.25 to 0.5 μg/ml for ofloxacin and 0.25 to 1.0 μg/ml for ciprofloxacin. The MIC for ampicillin was greater than 1,024 μg/ml. The results show clarithromycin and doxycycline are the two most effective drugs against C. pecorum. 相似文献