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101.
Ken Sasaki Tohru Tanaka Yoshinori Nishizawa Mitsunori Hayashi 《Applied microbiology and biotechnology》1990,32(6):727-731
Summary For the production of a herbicide, 5-amino-levulinic acid (ALA), from anaerobic digestion liquor, the utilization of the photosynthetic bacterium, Rhodobacter sphaeroides was examined. This bacterium could produce ALA extracelularly from this liquor with the addition of levulinic acid (LA), an inhibitor of ALA dehydratase (ALAD), and glycine, a precursor of ALA biosynthesis in the Shemin pathway. Succinate (another precursor) addition was unnecessary for ALA production. When repeated additions of LA were made together with glycine ALA production was significantly enhanced. However, above three additions of LA, ALA production was not further enhanced. The maximum value of ALA production attained was 4.2 mM (0.63 g/ 1), which was over double that of other ALA producers such as Chlorella vulgaris. Propionic acid was predominantly utilized compared with other lower fatty acids, suggesting that this might be converted to ALA via succinyl-coenzyme A (CoA) in the methylmalonyl-CoA pathway.Offprint requests to: Y. Nishizawa 相似文献
102.
A Nonneuronal Isoform of Cell Adhesion Molecule L1: Tissue-Specific Expression and Functional Analysis 总被引:4,自引:1,他引:3
Yasuo Takeda Hiroaki Asou Yoshinori Murakami Masayuki Miura Masaaki Kobayashi Keiichi Uyemura 《Journal of neurochemistry》1996,66(6):2338-2349
Abstract: The cell adhesion molecule L1 is a multifunctional protein in the nervous system characterizing cell adhesion, migration, and neurite outgrowth. In addition to full-length L1, we found an alternatively spliced variant lacking both the KGHHV sequence in the extracellular part and the RSLE sequence in the cytoplasmic part of L1. This L1 variant was expressed exclusively in nonneuronal cells such as Schwann cells, astrocytes, and oligodendrocytes, in contrast to the expression of the full-length L1 in neurons and cells of neuronal origin. To investigate the functions of the L1 variant, we established cell lines transfected with a cytoplasmic short L1 (L1cs) cDNA that lacks only the 12-bp segment encoding for the RSLE sequence. The promoting activities of homophilic cell adhesion, neurite outgrowth, and neuronal cell migration of L1cs-transfected cells (L4-2) were similar to those of full-length L1-transfected cells (L3-1), but the cell migratory activity of L4-2 itself was clearly lower than that of L3-1. In conclusion, the short form of L1 is a nonneuronal type, in contrast to the neuronal type of the full-length L1. Deletion of the four amino acids RSLE in the cytoplasmic region of L1 markedly reduced cell migratory activity, suggesting an importance of the RSLE sequence for the signaling events of neuronal migration mediated by L1. 相似文献
103.
104.
Protein Kinases Are Involved in Prolonged Acetylcholine Release from Rat Hippocampus Induced by Thyrotropin-Releasing Hormone Analogue NS-3 总被引:2,自引:0,他引:2
Michiko Oka Yoshinori Itoh Yojiro Ukai Yoshiaki Yoshikuni Kiyoshi Kimura 《Journal of neurochemistry》1996,66(5):1889-1893
Abstract: The effects of various protein kinase inhibitors on acetylcholine release from the rat hippocampus induced by the local application of NS-3 (montirelin hydrate, CG-3703), a thyrotropin-releasing hormone analogue, into the medial septum-diagonal band were examined using in vivo microdialysis. Perfusion of NS-3 (1 µ M ) into the medial septum-diagonal band for 20 min produced a pronounced and prolonged increase in the hippocampal acetylcholine efflux. Pretreatment of the medial septum-diagonal band with either K-252a, a nonselective protein kinase inhibitor, or selective protein kinase A inhibitor H-89 almost completely blocked the acetylcholine efflux evoked by NS-3, and selective protein kinase C inhibitor calphostin C inhibited the action of NS-3. On the other hand, NS-3 (0.1–10 µ M ) or TRH (1–100 µ M ) increased the cyclic AMP efflux from the medial septum-diagonal band in a concentration-dependent manner, as measured by microdialysis. These findings suggest that protein kinases A and C in the neurons of the medial septum-diagonal band are involved in the mechanism of the prolonged stimulation of acetylcholine release from the hippocampus induced by thyrotropin-releasing hormone and its analogue, NS-3. 相似文献
105.
Akira Yamada Masaaki Murakami Kenichi Ijima Hideo Yagita Ko Okumura Sakuzo Komatsu Toshimitsu Uede 《Microbiology and immunology》1996,40(7):513-518
The immunosuppressant FK506 prolongs allograft survival. However, at therapeutic doses it has significant side effects. A fusion protein consisting of the extracellular portion of CTLA4 and the Fc portion of human IgG (CTLA4IgG) also prolongs allograft survival, but large doses of CTLA4IgG are required for the induction of cardiac allograft acceptance. Therefore, we constructed a pentameric form of a new CTLA4 fusion protein, CTLA4IgM. We tested whether low doses of CTLA4IgG or CTLA4IgM in combination with subtherapeutic doses of FK506 can prolong allograft survival in a synergistic fashion. C57BL/6 (H-2b) neonatal hearts were transplanted to CBA/J (H-2k) mice in a heterotopic, nonvascularized cardiac allograft model. The findings demonstrate that a combination of low doses of FK506 plus a pentameric form of CTLA4Ig, CTLA4IgM, leads to significant graft survival, while a combination of FK506 plus CTLA4IgG does not. 相似文献
106.
M. Sunairi N. Iwabuchi K. Murakami F. Watanabe Y. Ogawa H. Murooka M. Nakajima 《Letters in applied microbiology》1996,22(1):66-69
M. SUNAIRI, N. IWABUCHI, K. MURAKAMI, F. WATANABE, Y. OGAWA, H. MUROOKA AND M. NAKAJIMA. 1996. Suitable conditions for the introduction of bacteriophage DNA into cells of Rhodococcus rhodochrous CF222 by electroporation were established, and penicillin G was found to enhance the transfection frequency. When conditions optimal for the parental strain were applied to its colony-morphological mutants, different transfection frequencies were observed. Penicillin G enhanced the transfection frequency of smooth and mucoidal mutants but not of rough mutants. 相似文献
107.
Ahmed S. Rahman Mieko Kimura Katsuhiko Yokoi Tanvir-E Naher Yoshinori Itokawa 《Biological trace element research》1996,53(1-3):57-64
Three groups of rats were fed two types of synthetic diets for 52 d. The—A group was allowed free access to a vitamin A-deficient
diet and showed classical signs of vitamin A deficiency. The brain was the only organ in our experiment where no significant
weight difference was present among the three groups. In the brain, calcium concentration was significantly higher in the—A
group when compared with the PF (Pair-fed; allowed restricted amount of control diet) and +A groups (allowed free access to
control diet). In the tibia, calcium and magnesium concentrations were significantly lower in the—A group when compared with
other two groups. Excessive accumulation of calcium in brain and apparently similar unbalance in bone, mineral concentration
were observed in central nervous system (CNS) degenerative diseases. Our results suggest that abnormal metabolism of calcium
and magnesium in some tissues and excessive accumulation of calcium in brain may be responsible for the development of neurological
disorders in vitamin A-deficient rats. 相似文献
108.
109.
110.
Takeuchi Yuichi; Murakami Mina; Nakajima Nobuyoshi; Kondo Noriaki; Nikaido Osamu 《Plant & cell physiology》1996,37(2):181-187
Photoinduced lesions in DNA, namely, cyclobutane pyrimidinedimers (CPDs) and pyrimidine-(6-4)-pyrimidone photoproducts[(6-4)photoproducts], in cucumber cotyledons that had been irradiatedwith naturally occurring levels of UV-B (290320 nm) werequantitated by enzyme-linked immunosorbent assays with monoclonalantibodies specific to each type of photolesion. Induction ofthese photolesions was dependent on temperature and their extentwas reduced by simultaneous irradiation with white light. Thedark repair of both types of photolesion was undetectable. Light-dependentremoval of (6-4)photoproducts was very slow, with 50% removalin 4 h. By contrast, 50% of initial CPDs were removed within15 min. Both photorepair processes were dependent on the intensityof white light and were sensitive to temperature. These resultsindicate that high photolyase activity is present in cucumbercotyledons and that repair activities in cucumber cotyledonsare different from those reported in Arabidopsis, in which (6-4)photoproductsare photorepaired more rapidly than CPDs. (Received October 13, 1995; Accepted December 28, 1995) 相似文献