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1.
RNA was degraded at 60 degrees C for 24 h by halophilic nuclease H in supernatants from broth cultures of Micrococcus varians subsp. halophilus containing 12% NaCl. Since contaminating 5'-nucleotidase exhibited almost no activity under these conditions, the 5'-GMP formed could be recovered from the reaction mixture, and the yield was 805 mg from 5 g of RNA. 相似文献
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Characterization and physiological function of glutathione reductase in Euglena gracilis z. 总被引:2,自引:0,他引:2
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The purified glutathione reductase was homogeneous on polyacrylamide-gel electrophoresis. It had an Mr of 79,000 and consisted of two subunits with a Mr of 40,000. The activity was maximum at pH 8.2 and 52 degrees C. It was specific for NADPH but not for NADH as the electron donor; the reverse reaction was not observed. The Km values for NADPH and GSSG were 14 and 55 microM respectively. The enzyme activity was markedly inhibited by thiol inhibitors and metal ions such as Hg2+, Cu2+ and Zn2+. Euglena cells contained total glutathione at millimolar concentration. GSH constituted more than 80% of total glutathione in Euglena under various growth conditions. Glutathione reductase was located solely in cytosol, as were L-ascorbate peroxidase and dehydroascorbate reductase, which constitute the oxidation-reduction cycle of L-ascorbate [Shigeoka et al. (1980) Biochem. J. 186, 377-380]. These results indicate that glutathione reductase functions to maintain glutathione in the reduced form and to accelerate the oxidation-reduction of L-ascorbate, which scavenges peroxides generated in Euglena cells. 相似文献
5.
R Morita S Morimoto E Koh K Fukuo S Kim K Itoh K Taniguchi T Onishi T Ogihara 《Biochemistry international》1989,18(3):647-653
Low density lipoprotein (LDL), a major cholesterol-carrying lipoprotein in the plasma, binds to its receptor through apoprotein B (Apo-B). The addition of LDL and Apo-B induced rapid (5 s), but transient increase in the inositol 1,4,5-trisphosphate (Ins-1,4,5-P3) level with K0.5 values of 1.1 and 0.07 microgram/ml, accompanied by increases of cytosolic free Ca2+ concentration [( Ca2+]i), in vascular smooth muscle cells (VSMC). The increases by LDL and Apo-B were both reduced by pretreatment of the VSMC with pertussis toxin. The early change in Ins-1,4,5-P3 involving a GTP-binding protein may function as an initial signal for the action of LDL in VSMC. 相似文献
6.
Hiroki Yamaue Hiroshi Tanimura Takuya Tsunoda Makoto Iwahashi Masaji Tani Mikiko Tamai Masaya Inoue 《Biotherapy》1990,2(3):247-259
The tumor-infiltrating lymphocytes (TILs) were cultured with interleukin 2 (IL-2) to induce the activated killer cells possessing autologous tumor-killing activity, and analysed their cell surface phenotypes and assessed anti-tumor killing activity. Furthermore, the activated TILs were transferred into 7 patients adoptively resulting in complete remission in a patient with pancreatic cancer and partial remission in another patient with gastric cancer.The cytotoxic activities of activated TILs at 3 weeks-incubation was 72 ± 15, 42 ± 26, 27 ± 21 and 25 ± 15% against K562, Daudi, KATO-III and autologous tumor, respectively. The negative selection method, indicated that the killer cells recognizing autologous tumor cells consisted of CD4- or CD8-positive T lymphocytes and CD16- or CD56-positive natural killer cells. The activated TILs could not only lyse cultured tumor cell lines, but also autologous tumor cells. 相似文献
7.
Onishi H Kamekura M Yokoi H Kobayashi T 《Applied and environmental microbiology》1988,54(11):2632-2635
A bioreactor with a column of flocculated cells of the moderate halophile Micrococcus varians subsp. halophilus which adsorbed the halophilic nuclease H was designed to be used in the production of 5' nucleotides from RNA. A remarkable characteristic of the flocculated cells was that they preferentially adsorbed much exogenous nuclease, excluding adsorbed 5' nucleotidase. Furthermore, desalting treatment of the flocculated cells in the presence of 2% MgSO(4) . 7H(2)O gave rise to selective inactivation of 5' nucleotidase without the loss of nuclease H activity, and 5'-guanylic acid was produced with the bioreactor. 相似文献
8.
Taichiro Goto Yajoi Katayama-Kumoi Masaya Tohyama Masao Yoshida 《Cell and tissue research》1992,267(2):215-222
Summary The distribution and development of serotonin-and RFamide-like immunoreactivities in the nervous system of Chaetognatha, Paraspadella gotoi, were examined in whole-mount preparations. In adults, a single serotonin-like immunoreactive (5HTLI) neuron and numerous RFamide-like immunoreactive (RFaLI) neurons were found in the central nervous system. Based on the structure of the fins, hooks, and eyes, seven postembryonic developmental stages were recognized. The most obvious features of the stages are: stage 1, newly hatched young; stage 2, elongation of a continuous lateral tail fin; stage 3, separation of the lateral and tail fins; stage 4, appearance of hooks; stage 5, pigmentation of eyes, stage 6, attachment by tail adhesive fins; stage 7, prey capture. Stage 1 did not show any immunoreactivity. The 5HTLI neuron first appeared at stage 4 and its axonal pathway became similar to the adult at stage 6. On the other hand, the RFaLI neurons appeared at stage 3 in the ventral ganglion. Some of their somata disappeared at stage 5 and the neuronal architecture resembled the adult at stage 7 although the RFaLI neurons in the cerebral ganglion were complete at the juvenile stage.We are sad to announce that Dr. M. Yoshida died on 29 October 1988 相似文献
9.
One-stage repair of blepharophimosis 总被引:4,自引:0,他引:4
Congenital blepharophimosis is a congenital anomaly characterized by abnormalities in the area of the eyes, including bilateral ptosis, shortening of the horizontal fissure of the lid, expansion of the intercanthal distance, and epicanthus inversus. The condition is subject to autosomal-dominant heredity and is said to occur more frequently in Orientals than in Occidentals. Over the past 9 years, we have surgically treated 11 cases of congenital blepharophimosis using a procedure in which levator resection and medial canthoplasty are performed in one stage. It has been commonly believed that when levator resection and medial canthoplasty are performed at the same time, tension in the eyelid becomes too strong to achieve favorable results; therefore, the standard procedure has been to divide the operation into two stages. In all 11 cases we experienced, however, it was possible to obtain good results with a single-stage operation. 相似文献
10.
K Itoh S Morimoto T Shiraishi K Taniguchi T Onishi Y Kumahara 《Biochemical and biophysical research communications》1988,150(1):263-270
Studies were made on the mechanism of the effect of parathyroid hormone (PTH) on the activity of (Ca2++Mg2+)-ATPase, a membrane bound Ca2+-extrusion pump enzyme from the basolateral membranes (BLM) of canine kidney (Km for free Ca2+ = 1.3 X 10(-7) M, Vmax = 200 nmol Pi/mg/min). At 1 X 10(-7) M free Ca2+, both PTH (10(-7)-10(-6) M) and cAMP (10(-6)-10(-4) M) stimulated (Ca2++Mg2+)-ATPase activity dose-dependent and their stimulatory effects were inhibited completely by 5 microM H-8, an inhibitor of cAMP-dependent protein kinase. PTH (10(-7) M) also caused 40% increase in 32P incorporation into the BLM and 5 microM H-8 inhibited this increase too. PTH (10(-7) M) was found to stimulate phosphorylation of a protein of Mr 9000 by cAMP dependent protein kinase and 5 microM H-8 was found to block this stimulation also. From these results, it is proposed that PTH stimulates (Ca2++Mg2+)-ATPase activity by enhancing its affinity for free Ca2+ via cAMP-dependent phosphorylation of a BLM protein of Mr 9000. 相似文献