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961.
Shinobu Iriuchijima Atsuko Keiyu Natsuko Kojima 《Bioscience, biotechnology, and biochemistry》2013,77(6):1593-1597
Enzymes and microorganisms were screened for the enantioselective hydrolysis of (±)-1-acetoxy-2,3-dichloropropane (1) which is convertible to epichlorohydrin. Pancreatin and steapsin from hog pancreas were found to hydrolyze (±)-1 asymmetrically to give (S)-1 of 90% enantiomeric excess (e.e.). From (S)-1 was synthesized the optically pure (S)-isomer of propranolol[1-isopropylamino-3-(1-naphthoxy)-2-propanol], one of the typical β-adrenergic blocking agents. 相似文献
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Yoshida H Arai S Hara KY Yamada R Ogino C Fukuda H Kondo A 《Applied microbiology and biotechnology》2011,89(5):1417-1422
Glutathione is a valuable tri-peptide that is widely used in the pharmaceutical, food, and cosmetic industries. Glutathione
is produced industrially by fermentation using Saccharomyces cerevisiae. We demonstrated that expression of amylase genes in glutathione-producing S. cerevisiae enables direct use of starch as a carbon source, thus eliminating the Crabtree effect that is caused by excess glucose. Consequently,
cell growth and glutathione productivity were significantly improved. This approach is potentially applicable to a variety
of fermentative processes for production of value-added chemicals under aerobic conditions. 相似文献
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Sato Y Suzuki S Kitabatake M Hara T Kojima M 《Cellular and molecular neurobiology》2011,31(4):605-614
Neurotrophins (NTs) regulate neuronal survival, differentiation, and synaptic plasticity through tropomyosin receptor kinases
(Trks). The molecular mechanisms underlying these functions, however, have remained incompletely understood. In the present
study, we first showed that brain-derived neurotrophic factor (BDNF) increased both the number of primary dendrites and dendritic
complexity in cultured hippocampal neurons. Since hippocampal neurons predominantly express the BDNF receptor TrkB, but not
the nerve growth factor (NGF) receptor Trk, we generated DNA constructs encoding the extracellular domain of TrkA fused with
the transmembrane and intracellular domain of TrkB and introduced these constructs into cultured hippocampal neurons. To visualize
the dendrites, the TrkA/TrkB fusion proteins were bicistronically expressed with green fluorescence protein (GFP). Interestingly,
the GFP-labeled neurons grew dendrites and activated the TrkA/TrkB receptors in response to NGF, but not BDNF. We next generated
a series of TrkA/TrkB receptors with mutations at tyrosine residues in the TrkB kinase domain, and sought to identify the
signaling pathway required for NT-induced dendrite outgrowth. Sholl analyses demonstrated that TrkB signaling through Shc,
but not through PLC-γ, plays a crucial role in NT-elicited dendritic outgrowth in hippocampal neurons. 相似文献
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Spain E Kojima R Kaner RB Wallace GG O'Grady J Lacey K Barry T Keyes TE Forster RJ 《Biosensors & bioelectronics》2011,26(5):2613-2618
Polyaniline (PANI) nanofibres (PANI-NF) have been modified with chemically grown gold nanoparticles to give a nanocomposite material (PANI-NF-AuNP) and deposited on gold electrodes. Single stranded capture DNA was then bound to the gold nanoparticles and the underlying gold electrode and allowed to hybridise with a complementary target strand that is uniquely associated with the pathogen, Staphylococcus aureus (S. aureus), that causes mastitis. Significantly, cyclic voltammetry demonstrates that deposition of the gold nanoparticles increases the area available for DNA immobilisation by a factor of approximately 4. EPR reveals that the addition of the Au nanoparticles efficiently decreases the interactions between adjacent PANI chains and/or motional broadening. Finally, a second horseradish peroxidase (HRP) labelled DNA strand hybridises with the target allowing the concentration of the target DNA to be detected by monitoring the reduction of a hydroquinone mediator in solution. The sensors have a wide dynamic range, excellent ability to discriminate DNA mismatches and a high sensitivity. Semi-log plots of the pathogen DNA concentration vs. faradaic current were linear from 150×10(-12) to 1×10(-6) mol L(-1) and pM concentrations could be detected without the need for molecular, e.g., PCR or NASBA, amplification. 相似文献