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81.
We describe the characterization of polyhydroxyalkanoate (PHA)-producing bacteria isolated from an ammunition-polluted soil in Kitakyushu City, Japan. Over 270 strains were evaluated for PHA accumulation based on a colony staining method using Nile red. Of these, nine strains were selected based on the intensity of Nile red fluorescence and the cells were quantitatively analyzed for PHA by gas chromatography. PHA accumulation was observed in five strains, all of which are inferred to be close to the Bacillus cereus group according to 16S rDNA sequence analysis. Interestingly, these strains produced a PHA copolymer, poly(3-hydroxybutyrae-co-3-hydroxyvalerate) [P(3HB-co-3HV)], with a 3HV fraction up to 2 mol% with glucose as a carbon source. Further characterization was performed on one isolate, B. cereus YB-4. Gel permeation chromatography analysis revealed that the number of average molecular weights of PHA accumulated in B. cereus YB-4 drastically changed from 722,000 to 85,000 over a 72-h cultivation period. Furthermore, the PHA synthase genes were cloned and the deduced amino acid sequences were determined. This study provides new insights into PHA biosynthesis by members of the B. cereus group. 相似文献
82.
New fluorescent analogues of menaquinone-4 and phylloquinone were prepared and their subcellular distribution monitored using a confocal laser scanning microscope. These analogues incorporate an FITC group anchored to the naphthoquinone skeleton through an amide bond expected to be resistant to metabolism. On their addition to the culture medium, fluorescence was readily observed inside a human osteosarcoma cell line. This result indicates that the fluorescent analogues penetrate into cells the same as vitamin K, and therefore, would be useful for achieving insight into the action mechanism of vitamin K. 相似文献
83.
Seunghee Jung Yuki TsukudaRie Kawashima Takumi IshikiAyaka Matsumoto Aya NakaniwaMiho Takagi Takuya NoguchiNobuyuki Imai 《Tetrahedron letters》2013
Acetaminophen analogues containing α-amino acid and fatty acids were easily synthesized in 77–99% yields from the corresponding mixed carbonic carboxylic anhydrides of α-amino acid and fatty acids using aniline derivatives in aqueous MeCN. 相似文献
84.
Lipase-catalyzed acylation of ethyl (1-hydroxyalkyl)phenylphosphinates afforded a single diastereomer in high enantiomeric excess. The substituent effect of the alkyl group toward the acylation using Candida antractica (CAL) was larger than that of an immobilized lipase from Pseudomonas fluorescens lipase (lipase AK). 相似文献
85.
Tanatani A Yokoyama A Azumaya I Takakura Y Mitsui C Shiro M Uchiyama M Muranaka A Kobayashi N Yokozawa T 《Journal of the American Chemical Society》2005,127(23):8553-8561
Poly(p-benzamide)s 1 bearing a chiral side chain on the nitrogen atom were synthesized by chain-growth polycondensation methodology. The polyamides exhibited well-defined molecular weights with narrow polydispersities. Solutions of the polyamides in several organic solvents (CH(3)CN, CHCl(3), and CH(3)OH) showed dispersion type CD signals characteristic of coupled-oscillator and much larger as compared with the corresponding monomer. The CD signals were dependent on the temperature and molecular weight of the polyamides but independent of the solvent, as far as examined. An exciton model analysis of the absorption and CD spectra provided a clear-cut picture for the secondary structure of these polyamides in solution that the N-alkylated poly(p-benzamide)s possess a right-handed helical conformation ((P)-helix). In the solid states, the results of X-ray crystallographic analysis of 4-(methylamino)benzoic acid oligomers substantiated that they have a helical conformation with three monomer units per turn. 相似文献
86.
Nishinaga T Tanatani A Oh K Moore JS 《Journal of the American Chemical Society》2002,124(21):5934-5935
A dynamic pool of m-phenylene ethynylene oligomers generated by sequence ligation using the imine metathesis reaction was equilibrated under a variety of conditions, and the mixture of products was analyzed by HPLC. The equilibration was performed in the presence and absence of rodlike ligand 2b, which exhibits an affinity for the helical oligomers that is very length specific. Among the eight oligomers generated during metathesis equilibrium, the formation of 22-mer 6b was enhanced in acetonitrile in the presence of 2b. This particular oligomer has the highest binding affinity for 2b. Quantitative analysis by HPLC of the products indicated that 6b was produced in 66% yield in the presence of 2 equiv 2b while a 37% yield was produced in the absence of 2b. Judging from the binding affinities of oligomers 6 with 2b, the equilibrium shifting was driven by the selective binding of 6b with 2b. 相似文献
87.
Summary
Spectrophotometric Determination of Aluminium with Chromal Blue G in the Presence of Cetyltrimethylammonium Chloride
Chromal Blue G (C. I. 43835) in the presence of cetyltrimethylammonium chloride is proposed for the spectrophotometric determination of microgram amounts of aluminium. The stoichiometric ratio of aluminium to Chromal Blue G is 14. Beer's law is obeyed from 0.01 to 0.16 ppm of aluminium. The molar absorptivity is 1.62×1051·mole–1·cm–1 at 660 nm. 相似文献
88.
Dr. Teresa Mena‐Barragán Aya Narita Dino Matias Dr. Gustavo Tiscornia Dr. Eiji Nanba Dr. Kousaku Ohno Dr. Yoshiyuki Suzuki Dr. Katsumi Higaki Prof. José Manuel Garcia Fernández Prof. Carmen Ortiz Mellet 《Angewandte Chemie (International ed. in English)》2015,54(40):11696-11700
A general approach is reported for the design of small‐molecule competitive inhibitors of lysosomal glycosidases programmed to 1) promote correct folding of mutant enzymes at the endoplasmic reticulum, 2) facilitate trafficking, and 3) undergo dissociation and self‐inactivation at the lysosome. The strategy is based on the incorporation of an orthoester segment into iminosugar conjugates to switch the nature of the aglycone moiety from hydrophobic to hydrophilic in the pH 7 to pH 5 window, which has a dramatic effect on the enzyme binding affinity. As a proof of concept, new highly pH‐responsive glycomimetics targeting human glucocerebrosidase or α‐galactosidase with strong potential as pharmacological chaperones for Gaucher or Fabry disease, respectively, were developed. 相似文献
89.
90.
Tomiko Kuhara Morimasa Ohse Yoshito Inoue Toshihiro Shinka Yoshiyuki Okano Haruo Shintaku Kazuhisa Hongou Toshio Miyawaki Wakaba Morinobu Hirosi Tamai Kenji Omura 《Rapid communications in mass spectrometry : RCM》2009,23(19):3167-3172
Nutrition and drugs are main environmental factors that affect metabolism. We performed metabolomics of urine from an 8‐year‐old patient (case 1) with epilepsy and an 11‐year‐old patient (case 2) with malignant lymphoma who was being treated with methotrexate. Both patients were receiving total parenteral nutrition (TPN). We used our diagnostic procedure consisting of urease pretreatment, partial adoption of stable isotope dilution, gas chromatography/mass spectrometry (GC/MS) measurement and target analysis for 200 analytes including organic acids and amino acids. Surprisingly, their metabolic profiles were identical to that of phenylketonuria. The neopterin level was markedly above normal in case 1, and both neopterin and biopterin were significantly above normal in case 2. Mutation analysis of genomic DNA from case 1 showed neither homozygosity nor heterozygosity for phenylalanine hydroxylase deficiency. The metabolic profiles of both cases were normal when they were not receiving TPN. TPN is presently prohibited for individuals who have inherited disorders that affect amino acid metabolism. Although the Phe content of the TPN was not the sole cause of the PKU profile, its effect, combined with other factors, e.g. specific medication or possibly underlying diseases, led to this metabolic abnormality. The present study suggests that GC/MS‐based metabolomics by target analysis could be important for assuring the safety of the treatments for patients receiving both TPN and methotrexate. Metabolomic profiling, both before and during TPN, is useful for determining the optimal nutritional formula not only for neonates, but also for young children who are known heterozygotes for metabolic disorders or whose status is unknown. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献