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991.
Involvement of Two Plasmids in Fenitrothion Degradation by Burkholderia sp. Strain NF100 总被引:4,自引:0,他引:4
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A bacterium capable of utilizing fenitrothion (O,O-dimethyl O-4-nitro-m-tolyl phosphorothioate) as a sole carbon source was isolated from fenitrothion-treated soil. This bacterium was characterized taxonomically as being a member of the genus Burkholderia and was designated strain NF100. NF100 first hydrolyzed an organophosphate bond of fenitrothion, forming 3-methyl-4-nitrophenol, which was further metabolized to methylhydroquinone. The ability to degrade fenitrothion was found to be encoded on two plasmids, pNF1 and pNF2. 相似文献
992.
Yuki Nakamura Xiuyu Shi Tomohiro Numata Yasuo Mori Ryuji Inoue Christoph Lossin Tallie Z. Baram Shinichi Hirose 《PloS one》2013,8(12)
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channel-mediated currents, known as I
h, are involved in the control of rhythmic activity in neuronal circuits and in determining neuronal properties including the resting membrane potential. Recent studies have shown that HCN channels play a role in seizure susceptibility and in absence and limbic epilepsy including temporal lobe epilepsy following long febrile seizures (FS). This study focused on the potential contributions of abnormalities in the HCN2 isoform and their role in FS. A novel heterozygous missense mutation in HCN2 exon 1 leading to p.S126L was identified in two unrelated patients with FS. The mutation was inherited from the mother who had suffered from FS in a pedigree. To determine the effect of this substitution we conducted whole-cell patch clamp electrophysiology. We found that mutant channels had elevated sensitivity to temperature. More specifically, they displayed faster kinetics at higher temperature. Kinetic shift by change of temperature sensitivity rather than the shift of voltage dependence led to increased availability of I
h in conditions promoting FS. Responses to cyclic AMP did not differ between wildtype and mutant channels. Thus, mutant HCN2 channels cause significant cAMP-independent enhanced availability of I
h during high temperatures, which may contribute to hyperthermia-induced neuronal hyperexcitability in some individuals with FS. 相似文献
993.
Takayuki Hoshino Yuki Hidaka Takehide Kosuge Masumi Hasegawa Tomoyuki Saito Tadaatsu Nakahara 《FEMS microbiology letters》1994,117(2):175-179
Abstract Recombination indexes were measured among six Trp− mutants of Thermus thermophilus HB27 by reciprocal transformation among the mutants. Based on the index values, the order and distance of four closely located mutation sites were predicted. Cloning and sequence analysis of the mutants revealed that the order and distance among the mutation sites predicted from the index values were correct. A similar relationship between the index value and real distance was also obtained for two Pro− mutants. These results suggest that transformation can be used as a tool for genetic fine mapping in T. thermophilus . 相似文献
994.
Shinichi Nakamura Masato Mikawa Naomi Tanabe Kiyotaka Yamakawa Shoki Nishida 《Microbiology and immunology》1982,26(11):985-992
A total of 80 strains of Clostridium difficile, 33 toxigenic and 11 nontoxigenic clindamycin (CLDM)-sensitive (MIC less than 12.5 μg/ml), and 23 toxigenic and 13 nontoxigenic CLDM-resistant (MIC 200 to 6,400 μg/ml) were tested for cytotoxin production in the presence of CLDM. None of the 24 nontoxigenic strains produced cytotoxin regardless of the presence of CLDM and only six out of the 56 toxigenic strains showed 16- to 64-fold higher levels of cytotoxic activity in the presence of CLDM at the concentrations of 1/2 to 1/32 of the MIC than in the absence of CLDM; all of the six strains were CLDM sensitive. Further studies revealed that addition of CLDM to the culture caused enhanced cytotoxin synthesis, and that the maximum production of cytotoxin was obtained when CLDM was added to the medium at the time of inoculation or of the ensuing early logarithmic phase. Also, the influence of other antibiotics on the effect of CLDM was examined. Addition of metronidazole, vancomycin, chloramphenicol, cephaloridine, or penicillin, which induced cytotoxin to medium containing CLDM did not increase the effect of CLDM any further. Addition of CLDM to medium containing tetracycline, which inhibited cytotoxin production, induced cytotoxin production but not fully. 相似文献
995.
T Sakurai S Sawada S Suzuki A Nakahara 《Biochemical and biophysical research communications》1985,131(2):647-652
Reoxidation process of reduced cucumber ascorbate oxidase (1.10.3.3) with dioxygen was investigated in detail through absorption, circular dichroic (CD) and electron paramagnetic resonance (EPR) spectra. One of the three type I coppers and the type II copper were reoxidized more rapidly than other type I coppers. The principal active site of ascorbate oxidase was considered to be comprised of one type I, one type II and a pair of type III coppers similarly to the active sites in laccase and ceruloplasmin. Remaining two type I and a pair of type III coppers were also disclosed to contribute to the oxidation of L-ascorbate. 相似文献
996.
Tadahiro Karasawa Shin Takasawa Kiyotaka Yamakawa Hideto Yonekura Hiroshi Okamoto Shinichi Nakamura 《FEMS microbiology letters》1995,130(2-3):201-204
Abstract NAD+ -glycohydrolase from Streptococcus pyogenes was purified by successive chromatography on CM Sepharose CL-6B, Sephacryl S-200 HR and hydroxyapatite. The purified enzyme possessed synthesis and hydrolysis activities of cyclic ADP-ribose (cADPR), a newly found second messenger for Ca2+ mobilisation, along with cleavage activity of the ribose-nicotinamide bond in NAD+ . 相似文献
997.
Tsehaye Tesfamariam H. Yoshinaga S. P. Deshpande P. Srinivasa Rao K. L. Sahrawat Y. Ando K. Nakahara C. T. Hash G. V. Subbarao 《Plant and Soil》2014,378(1-2):325-335
Aims
Organically-certified orchard floor management was assessed for its ability to improve soil fertility and biological activity and apple orchard performance.Methods
‘Ambrosia’/B9 apple was maintained for the first six growing seasons with four orchard floor treatments, including 1) annual compost application; 2) in-row application of mown alfalfa grown between the rows; 3) bark mulch plus in-row application of mown hay; and 4) black plastic mulch.Results
Soil collected from 0 to 10 cm indicated high soil organic matter and exchangeable K were measurable for all treatments by the second year. After 6 years, highest organic matter, total-, particulate- and mineral–C were associated with soil beneath the bark mulch treatment which also had most vigorous trees, decreased leaf N and elevated leaf P and K. Addition of alfalfa and bark mulch were equally effective at maintaining high exchangeable K and soil phosphatase enzymes, high total and particulate-N by the fourth year.Conclusions
Despite measurable improvements in soil properties among treatments, fruit yield and quality were minimally affected by management implying no limitations to adoption of any of the assessed strategies. 相似文献998.
Yusuke Goto Rika Nishikawa Satoko Kojima Takeshi Chiyomaru Hideki Enokida Satoru Inoguchi Takashi Kinoshita Miki Fuse Shinichi Sakamoto Masayuki Nakagawa Yukio Naya Tomohiko Ichikawa Naohiko Seki 《FEBS letters》2014
Our recent study of the microRNA expression signature of prostate cancer (PCa) revealed that microRNA-224 (miR-224) is significantly downregulated in PCa tissues. Here, we found that restoration of miR-224 significantly inhibits PCa cell migration and invasion. Additionally, we found that oncogenic TPD52 is a direct target of miR-224 regulation. Silencing of the TPD52 gene significantly inhibits cancer cell migration and invasion. Moreover, TPD52 expression is upregulated in cancer tissues and negatively correlates with miR-224 expression. We conclude that loss of tumour-suppressive miR-224 enhances cancer cell migration and invasion in PCa through direct regulation of oncogenic TPD52. 相似文献
999.
Ken Tokizawa Shinichi Sawada Tatsuo Oka Akinori Yasuda Tetsuo Tai Hirofumi Ida Kazumi Nakayama 《International journal of biometeorology》2014,58(9):1919-1925
This study compared heat strain during walking while wearing impermeable protective suits between fan-precooling and nonprecooling conditions. Six males engaged in 60 min of walking at a moderate speed (~2.5 km/h) in a hot environment (37 °C, 40 % relative humidity). Fanning using a fan (4.5 m/s) and spraying water over the body before wearing the suits produced significantly lower rectal temperature before the walking (37.3?±?0.1 °C vs. 37.0?±?0.1 °C, P?0.05). In addition, whilst walking, rectal temperature was significantly lower in the precooling condition (maximum difference: 0.4 °C at 15 min of walking; 38.0?±?0.1 °C vs. 37.8?±?0.1 °C at the end of walking, P?0.05). Although skin temperature decreased during fanning, no difference was observed during walking. Heart rate was lower in the precooling condition during the early stages of walking. Thermal and fatigue perceptions whilst walking did not differ between the conditions. Body weight loss was significantly lower in the precooling condition. These results may indicate that fan precooling attenuates exertional heat strain while wearing impermeable protective clothing. The fan-cooling method is practical, convenient, and yields lower heat strain during prolonged moderate exertion. 相似文献