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511.
We developed a local AIT using PEL cultured with TCGF combined with preadministration of OK-432. Twenty-six patients of breast cancer with pleural effusion have been treated with this therapy since 1983. PEL expanded and tumor cells collapsed by day 9 in culture with TCGF. Cultured PEL possessed significantly higher cytotoxic activity against autologous tumor cells than PBL cultured in the same condition (p < 0.05), but there was no difference between their cytotoxic activities against K562. The proliferation rate of PEL obtained after intrapleural administration of OK-432 was higher than that obtained before OK-432 (p < 0.01). Moreover, the cytotoxic activities against both autologous tumor and K562 of cultured PEL obtained after OK-432 administration was significantly (p < 0.05) higher than those cultured PEL obtained before.Cultured PEL (1 x 108 - 6 x 109) were transferred into the pleural cavity after the intrapleural administration of OK-432 (1–5 KE). The volume of pleural effusion increased temporarily after the administration of OK-432 but significantly (p < 0.01) decreased after AIT. Tumor cells disappeared cytologically in 22 patients at the last puncture of pleural effusion. Pleural effusion disappeared completely in 19 of 26 patients and decreased by more than 50% in volume in 6 patients. Performance status improved in 22 patients. The response rate for OK-432-combined AIT in the present study was 96%. The survival period of the patients treated by OK-432-combined AIT in this trial was significantly (p < 0.002) prolonged compared to that of the patients receiving chemotherapy alone. The side effects were fever and general malaise after OK-432 administration but no critical toxicity was observed.  相似文献   
512.
Pseudomonas putida Which Can Grow in the Presence of Toluene   总被引:7,自引:3,他引:4       下载免费PDF全文
A Pseudomonas putida strain able to grow in the presence of more than 50% toluene was isolated from soil. The strain was tolerant of other toxic solvents, including aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, alcohols, and ethers. The stability of the solvent tolerance of strain IH-2000 was stimulated by addition of Mg2+ and Ca2+ to the medium containing toluene.  相似文献   
513.
A trehalose synthase (TSase) that catalyzes the synthesis of trehalose from d-glucose and α-d-glucose 1-phosphate (α-d-glucose 1-P) was detected in a basidiomycete, Grifola frondosa. TSase was purified 106-fold to homogeneity with 36% recovery by ammonium sulfate precipitation and several steps of column chromatography. The native enzyme appears to be a dimer since it has apparent molecular masses of 120 kDa, as determined by gel filtration column chromatography, and 60 kDa, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Although TSase catalyzed the phosphorolysis of trehalose to d-glucose and α-d-glucose 1-P, in addition to the synthesis of trehalose from the two substrates, the TSase equilibrium strongly favors trehalose synthesis. The optimum temperatures for phosphorolysis and synthesis of trehalose were 32.5 to 35°C and 35 to 37.5°C, respectively. The optimum pHs for these reactions were 6.5 and 6.5 to 6.8, respectively. The substrate specificity of TSase was very strict: among eight disaccharides examined, only trehalose was phosphorolyzed, and only α-d-glucose 1-P served as a donor substrate with d-glucose as the acceptor in trehalose synthesis. Two efficient enzymatic systems for the synthesis of trehalose from sucrose were identified. In system I, the α-d-glucose 1-P liberated by 1.05 U of sucrose phosphorylase was linked with d-glucose by 1.05 U of TSase, generating trehalose at the initial synthesis rate of 18 mmol/h in a final yield of 90 mol% under optimum conditions (300 mM each sucrose and glucose, 20 mM inorganic phosphate, 37.5°C, and pH 6.5). In system II, we added 1.05 U of glucose isomerase and 20 mM MgSO4 to the reaction mixture of system I to convert fructose, a by-product of the sucrose phosphorylase reaction, into glucose. This system generated trehalose at the synthesis rate of 4.5 mmol/h in the same final yield.Trehalose (1-α-d-glucopyranosyl-α-d-glucopyranoside) is a nonreducing disaccharide with an α,α-1,1 glycosidic linkage and is widely distributed in plants, insects, fungi, yeast, and bacteria (7). Due to the absence of reducing ends in trehalose, it is highly resistant to heat, pH, and Maillard’s reaction (24). In trehalose-producing organisms, this compound may serve as an energy reserve, a buffer against stresses such as desiccation and freezing, and a protein stabilizer (5, 7, 26, 31, 32). If trehalose can be produced economically, then it has potential commercial applications as a sweetener, a food stabilizer, and an additive in cosmetics and pharmaceuticals (6, 25). Recently, trehalose production through fermentation of yeast (17) and Corynebacterium (30), enzymatic processes from starch (18, 34) and maltose (19, 22, 23, 33), and extraction from transformed plants (10) has been reported.Our approach to trehalose production is to use an enzymatic process to produce trehalose from sucrose, one of the least expensive sugars. Since sucrose is efficiently converted to α-d-glucose 1-phosphate (α-d-glucose 1-P) and fructose by sucrose phosphorylase (SPase), we screened microorganisms for an enzyme that converts α-d-glucose 1-P to trehalose on the assumption that the combination of the putative trehalose synthase (TSase) and SPase would convert sucrose into trehalose. Although similar enzyme activities have been reported in the basidiomycete Flammulina velutipes (11) and in the yeast Pichia fermentans (27), these enzymes have not been well characterized.Our objectives were (i) to screen microorganisms, primarily fungi, for TSase activity; (ii) to purify and characterize the TSase; (iii) to identify the enzymatic process by which trehalose is produced from sucrose; and (iv) to identify an enzymatic process for production of trehalose from sucrose in which the fructose component is also converted to trehalose.  相似文献   
514.
Several barophilic Shewanella species have been isolated from deep-sea sediments at depths of 2,485– 6,499 m. From the results of taxonomic studies, all of these isolates have been identified as strains of Shewanella benthica except for strain DSS12. Strain DSS12 is a member of a novel, moderately barophilic Shewanella species isolated from the Ryukyu Trench at a depth of 5,110 m. On Marine Agar 2216 plates, this organism produced a violet pigment, whereas the colonies of other isolates (S. benthica) were rose-colored. Phylogenetic analysis based on 16 S ribosomal RNA gene sequences showed that strain DSS12 represents a separate lineage within the genus Shewanella that is closely related to S. benthica and particularly to the members of the Shewanella barophiles branch. The temperature range for growth and some of the biochemical characteristics indicate that strain DSS12 differs from other Shewanella species. Furthermore, strain DSS12 displayed a low level of DNA similarity to the Shewanella type strains. Based on these differences, it is proposed that strain DSS12 represents a new deep-sea Shewanella species. The name Shewanella violacea (JCM 10179) is proposed. Received: 15 May 1998 / Accepted: 15 July 1998  相似文献   
515.
A pressure-regulated operon has been cloned and sequenced from deep-sea barophilic Shewanella strains. To understand pressure-regulated mechanisms of gene expression, a regulatory element upstream of the pressure-regulated operon from Shewanella sp. strain DSS12 was studied. Regions A and B were classified by sequence analysis. A unique octamer motif, AAGGTAAG, was found to be repeated in tandem 13 times in region B. An electrophoretic mobility shift assay demonstrated that a σ54-like factor recognizes region A and other unknown factors recognize region B. Different shift patterns of the protein–DNA complexes were observed when extracts of cells cultured at 0.1 MPa or 50 MPa were incubated with a DNA probe specific for region B. These results indicate that the deep-sea strain DSS12 expresses different DNA-binding factors under different pressure conditions. Received: January 22, 1998 / Accepted: February 16, 1998  相似文献   
516.
The genes encoding membrane-bound nitrate reductase and its locus from Pseudomonas sp. strain MT-1, which is isolated from the sediment of Mariana Trench, were identified. To some extent, the gene organization in the cluster was different from those of other Pseudomonads. Quite interestingly, two genes encoding putative nitrate transporter (narK and narM) showed higher homologies to counterparts of organisms belonging to other genera than those of Pseudomonads. Especially, narM showed no significant homology to the genes for nitrate transporter of Pseudomonads, and was homologous to those of some marine bacteria. Further, arrangements of NarL- and Fnr-binding motifs in the cluster were different from those of P. stutzeri, closely related strain with MT-1. These observations clearly indicated that lateral transfer of genes in nar gene cluster had occurred in deep sea, and it may contribute to bacterial adaptation to environment of there.  相似文献   
517.
Halophilic and halotolerant bacteria were isolated from soil samples of a Japanese salt field, an environment where salt concentrations vary annually. From 1 g of each of the five samples collected, over 1×103 bacterial colonies (colony forming units (cfu)g-1) grew on agar medium containing 2M Na+. In contrast, 0–4 bacterial colonies (cfu g-1) were observed on agar medium containing 4M Na+. Two of the five samples contained numerous bacteria (102–103 cfu g-1) capable of growth on a 2M Na+ alkaline (pH=9.5) medium, while few bacterial colonies were observed from the other three samples. Only one of the five samples was shown to contain bacteria capable of growth on a 4M Na+ alkaline medium. Most of the bacteria isolated on 4M Na+ agar were eubacteria, but one extreme halophile (TR-1, already described as Haloarcula japonica JCM7785) was also isolated. The 16S rRNA sequence of TR-1 was determined and shows high homology (94.4–98.5%) to Ha. marismortui and Ha. sinaiiensis. These results suggested that: 1) environments with seasonally varying salinity can harbour halotolerants as well as halophiles and, 2) closely related halophiles can be isolated from geographically distant habitats.  相似文献   
518.
Application of electric pulses (1000 V/cm, 20 m sec duration) to macroliposomes containing pure stable H+-ATPase (F0·F1) resulted in synthesis of ATP. Microliposomes containing F0·F1 showed very little ATP synthesis under the same conditions. The amount of ATP synthesized was increased by increasing the number of electric pulses applied and decreased by addition of either an uncoupler or an energy transfer inhibitor.  相似文献   
519.
The hydrothermal-vent gastropod Alviniconcha aff. hessleri from the Kairei hydrothermal field on the Central Indian Ridge houses bacterium-like cells internally in its greatly enlarged gill. A single 16S rRNA gene sequence was obtained from the DNA extract of the gill, and phylogenetic analysis placed the source organism within a lineage of the epsilon subdivision of the Proteobacteria. Fluorescence in situ hybridization analysis with an oligonucleotide probe targeting the specific epsilonproteobacterial subgroup showed the bacterium densely colonizing the gill filaments. Carbon isotopic homogeneity among the gastropod tissue parts, regardless of the abundance of the endosymbiont cells, suggests that the carbon isotopic composition of the endosymbiont biomass is approximately the same as that of the gastropod. Compound-specific carbon isotopic analysis revealed that fatty acids from the gastropod tissues are all 13C enriched relative to the gastropod biomass and that the monounsaturated C16 fatty acid that originates from the endosymbiont is as 13C enriched relative to the gastropod biomass as that of the epsilonproteobacterial cultures grown under chemoautotrophic conditions. This fractionation pattern is most likely due to chemoautotrophy based on the reductive tricarboxylic-acid (rTCA) cycle and subsequent fatty acid biosynthesis from 13C-enriched acetyl coenzyme A. Enzymatic characterization revealed evident activity of several key enzymes of the rTCA cycle, as well as the absence of ribulose-1,5-bisphosphate carboxylase/oxygenase activity in the gill tissue. The results from anatomic, molecular phylogenetic, bulk and compound-specific carbon isotopic, and enzymatic analyses all support the inference that a novel nutritional strategy relying on chemoautotrophy in the epsilonproteobacterial endosymbiont is utilized by the hydrothermal-vent gastropod from the Indian Ocean. The discrepancies between the data of the present study and those of previous ones for Alviniconcha gastropods from the Pacific Ocean imply that at least two lineages of chemoautotrophic bacteria, phylogenetically distinct at the subdivision level, occur as the primary endosymbiont in one host animal type.  相似文献   
520.
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