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81.
pKJ1, a naturally occurring conjugative plasmid coding for toluene degradation and resistance to streptomycin and sulfonamides. 总被引:5,自引:1,他引:4
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Pseudomonas sp. TA8 isolated by m-toluate enrichment from an aqueous sample metabolized toluene and m- and p-xylenes via the meta cleavage pathway, and manifested specific resistance to streptomycin and sulfonamides. A variety of experiments revealed that the pKJ1 plasmid of about 150 megadaltons carried by TA8 specified both the toluene and xylene degradative function (the Tol function) and streptomycin/sulfonamide resistance. The deletion of a segment of pKJ1 (about 22 megadaltons) resulted in the loss of the Tol function. pKJ1 was not assigned to Pseudomonas incompatibility group P-1, P-2, P-3, or P-9. 相似文献
82.
N Nishi M Kataoka G Soe T Kakuno T Ueki J Yamashita T Horio 《Journal of biochemistry》1979,86(5):1211-1234
1. The membrane of Rhodospirillum rubrum chromatophores was disintegrated with mild detergents (cholate and deoxycholate) in order to study the spatial arrangement of the functional proteins in the photochemical apparatus and the electron transport system in the membrane. 2. The components solubilized from the membrane by a mixture of cholate and deoxycholate (C-DOC) were separated into four fractions by molecular-sieve chromatography in the presence of C-DOC; they were designated as F1, F2, F3, and F4 in the order of elution. The fractions were further purified by repeated molecular-sieve chromatography in the presence of C-DOC until each fraction was chromatographically homogeneous. 3. F1 appeared to be conjugated forms of F2. 4. The purified F2 was composed of a rigid complex having a weight of 7 X 10(5) daltons, containing approximately 10 different kinds of protein species with molecular weights of 3.8 X 10(4), 3.6 X 10(4), 3.5 X 10(4), 2.8 X 10(4), 2.7 X 10(4), 2.6 X 10(4), 1.3 X 10(4), 1.2 X 10(4), 1.1 X 10(4), and 1.0 X 10(4). The complex contained 33 bacteriochlorophylls, 4 iron atoms, and 90 phosphates, but no cytochrome, ubiquinone, or phospholipid. It showed the same reaction center activity as chromatophores, indicating that the complex was a unit of the photochemical apparatus (photoreaction unit). Each chromatophore of average size was estimated to possess about 24 photoreaction units. 5. The purified F3 showed an absorbance spectrum characteristic of reaction centers, and contained 3.4 bacteriochlorophylls, 2.0 bacteriopheophytins, and 1.9 acid-labile iron atoms, but no cytochrome or ubiquinone (C-DOC reaction center). It had a weight of 1.2 X 10(5) daltons, and the main components were 4 protein species with molecular weights of 2.8 X 10(4), 2.7 X 10(4), 2.6 X 10(4), and 1.0 X 10(4). 6. The purified F4 showed a molecular weight of about 11,000, and contained one mole of ubiquinone-10 per mole (ubiquinone-10 protein). 7. The reaction center activity of C-DOC reaction centers was stimulated by ubiquinone-10 protein. In addition, the reaction center oxidized reduced cytochrome c2 in the light, provided that ubiquinone-10 protein was present (photo-oxidase activity). 相似文献
83.
We have purified to homogeneity murine alpha-fetoprotein (MAFP) and determined the amino acid sequence of the first twenty-four residues. The N-terminal sequence obtained shows a high degree of homology with human and rat AFP's, but not human or rat albumins. The C-terminal residue is the same as human and “slow” rat AFP, but different from the corresponding albumins. We conclude that the AFP's are derived from homologous genes which are at best distantly related to the ancestral gene for albumin. The single C-terminal residue and N-terminal sequence suggests that the multiple forms of MAFP observed by others are due to carbohydrate micro-heterogeneity. 相似文献
84.
Akio Shiraishi Nobuyuki Miyachi 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1976,110(1):97-109
Summary The proboscis extension reponse of the blowfly during stimulation of the tarsal sugar receptors was inhibited by the presence of NaCl. Acceptance thresholds for sucrose in various concentrations of NaCl were measured. The median acceptance thresholds for sucrose in mixtures of 0.01, 0.25, 0.5 and 1.0 M NaCl were 1.8 × 10–3, 6.0 × 10–3, 1.2 × 10–2, and 2.0 × 10–2 M, respectively. Concentration-response curves for sucrose in the tarsal D-type sugar receptor shifted to the right under the existence of high concentration of NaCl. Number of impulses per D-type sugar receptor at the median acceptance thresholds described above were 7.5, 8.4, 6.8 and 10.4 for the first 0.1 s of stimulation, respectively. The average number was 8.2 impulses per 0.1 s. Comparisons were made between the behavioral acceptance thresholds (1) on one leg exposed to sucrose mixed with 0.01 M NaCl and (2) on two contralateral legs, one of which was exposed to sucrose in 0.01 M NaCl and the other to 0.5 M NaCl alone. The acceptance thresholds from two experiments agreed with each other. The median threshold value was 1.7 × 10–2 M sucrose. Behavioral inhibition by NaCl in mixtures with sucrose can be explained by its peripheral inhibition of sugar receptors.This research was supported in part by ITO foundation and Scientific Research Fund from the Ministry of Education of Japan. 相似文献
85.
Nobuyuki Itoh Ikuo Yamashina 《Biochemical and biophysical research communications》1975,67(2):840-845
Taka amylase A glycopeptide (TA-GP) strongly inhibited the interaction of antimannan (antibodies directed towards mannan from ) with yeast mannan, whereas ovalbumin glycopeptide (OA-GP) did so only poorly. We inferred that this is due to the strong reactivity of antimannan with terminal trimannosides composed of Manα1→2Man or Manα1→3Man linkages which occur in mannan and TA-GP. In contrast, TA-GP and OA-GP were nearly equally reactive with concanavalin A having the ability to interact with terminal mannose and 2-0-mannose residues which occur abundantly in these glycopeptides. Thus, antimannan should be useful as a probe for characterizing glycoproteins from extracellular fluids or cellular membranes. 相似文献
86.
The high PAL activity in carrot cells in suspension culture was found at the linear and early stationary phases, with concomitant increases in phenylal 相似文献
87.
88.
89.
Nobuyuki Terakado Hayami Azechi Kiyoji Ninomiya Tsuguaki Fukuyasu Takeshi Shimizu 《Microbiology and immunology》1974,18(1):45-48
Bordetella bronchiseptica strains isolated from the nasal cavities of young pigs in Japan from 1969 to 1972 were surveyed for drug resistance and distribution of R factors. Of 304 strains examined, 71 (23%) were resistant to either one or more of following three drugs, streptomycin (SM), sulfadimethoxine (SA), and aminobenzyl penicillin (APC). Triple (SM.SA.APC)-resistance was most frequent among these resistant strains. Strains of double (SM. SA)- or single (SM)- and (SA)-resistance were also isolated, but were very few in numbers. Of the 71 drug-resistant strains, 61 (86%) were found to carry R factors which were capable of conjugal transfer. All of these R factors had the triple (SM.SA.APC)-resistant markers and were identified as fi– (no fertility inhibition) type. The (SM.SA.APC)-resistant strains carrying R factors had been isolated from pigs reared on various farms in different districts, and consequently the prevalence of B. bronchiseptica strains carrying R factors was considered to be relatively wide-spread in young pigs. 相似文献
90.
Ohara Chisato Sekiguchi Atsushi Takakura Shu Endo Yuka Tamura Naho Kikuchi Hiroe Maruo Kazushi Sugawara Norio Hatano Kenji Kawanishi Hitomi Funaba Misako Sugawara Ayako Nohara Nobuhiro Kawai Keisuke Fukudo Shin Sudo Nobuyuki Cooper Zafra Yoshiuchi Kazuhiro Ando Tetsuya 《BioPsychoSocial medicine》2020,14(1):1-3
Although fatigue is a common and distressing symptom in cancer survivors, the mechanism of fatigue is not fully understood. Therefore, this study aims to investigate the relation between the fatigue and mindfulness of breast cancer survivors using anxiety, depression, pain, loneliness, and sleep disturbance as mediators. Path analysis was performed to examine direct and indirect associations between mindfulness and fatigue. Participants were breast cancer survivors who visited a breast surgery department at a university hospital in Japan for hormonal therapy or regular check-ups after treatment. The questionnaire measured cancer-related-fatigue, mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance. Demographic and clinical characteristics were collected from medical records. Two-hundred and seventy-nine breast cancer survivors were registered, of which 259 answered the questionnaire. Ten respondents with incomplete questionnaire data were excluded, resulting in 249 participants for the analyses. Our final model fit the data well (goodness of fit index = .993; adjusted goodness of fit index = .966; comparative fit index = .999; root mean square error of approximation = .016). Mindfulness, anxiety, depression, pain, loneliness, and sleep disturbance were related to fatigue, and mindfulness had the most influence on fatigue (β = − .52). Mindfulness affected fatigue not only directly but also indirectly through anxiety, depression, pain, loneliness, and sleep disturbance. The study model helps to explain the process by which mindfulness affects fatigue. Our results suggest that mindfulness has both direct and indirect effects on the fatigue of breast cancer survivors and that mindfulness can be used to more effectively reduce their fatigue. It also suggests that health care professionals should be aware of factors such as anxiety, depression, pain, loneliness, and sleep disturbance in their care for fatigue of breast cancer survivors. This study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN number. 000027720) on June 12, 2017. 相似文献