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11.
Soh Chang-Ho; Kamiya Yuji; Yoshida Shigeo; Yamane Hisakazu; Takahashi Nobutaka 《Plant & cell physiology》1994,35(7):1037-1042
Oryzains, cysteine proteinases of rice seeds, are induced byGA3 in germinating rice seeds [Abe et al. (1987) Agric. Biol.Chem. 51: 1509]. The effects of GA1, GA3, GA4, GA9, and GA20on the production of oryzain and -amylase were investigatedin embryoless half- and whole-seeds of rice (cv. Nipponbare).When gibberellins (GAs) were incubated with embryoless half-seeds,GA1, GA3 and GA4 induced oryzain and -amylase, but GA9, andGA20 did not. GA9 and GAM induced oryzain and -amylase productionin whole seeds, but this production was inhibited by the simultaneousapplication of prohexadione, an inhibitor of 2ß- and3ß-hydroxylation of GAs. Prohexadione did not inhibitthe activities of oryzain and -amylase induced by GA1. Theseresults suggest that GAs possessing the 3ß-hydroxylgroup induce activities of oryzain and -amylase in rice seedsand that GA9 and GA20 have activity only after they are convertedmetabolically to active GAs, probably GA4 and GA1, respectively.GA1, was more active than GA4 in both half seeds and wholeseeds incubation. Oryzain and -amylase activities induced byGA4 were significantly inhibited in the presence of 104M prohexadione. This suggests that the conversion of GA1, toGA4 (13-hydroxylation) might be inhibited at a high dose ofprohexadione in whole seeds.
4Present address: Institute of Food Development, Kyung Hee University,Suwon 449-701, Korea 相似文献
12.
Zhao Ying Hiromasa Tojo Takanori Komatsubara Manabu Nakagawa Masami Inada Sumio Kawata Yuji Matsuzawa Mitsuhiro Okamoto 《生物化学与生物物理学报:疾病的分子基础》1994,1226(2):201-205
Enzyme activity, protein contents, and mRNA contents of group II phospholipase A2 (PLA2) in hepatocellular carcinoma (HCC) surgically obtained from 8 patients were compared with those in either its neighboring liver tissues or control liver tissues. The PLA2 specific activity towards the mixed micelles of 1-palmitoyl-2-oleoyl-phosphatidylglycerol and cholate was significantly greater in the tumor tissues (6.62 ± 1.46 nmol/min/mg) than those in the surrounding liver tissues (1.33 ± 0.22 nmol/min/mg) and controls (0.43 ± 0.04 nmol/min/mg). The results of immunoblot analysis using a specific anti-human group II PLA2 antibody and of Northern blot analysis using a human group II PLA2 cDNA as a probe demonstrated that group II PLA2 was responsible for the increased enzyme activity. The contents of immunoreactive group II PLA2 in the tumor tissues (8.81 ± 1.24 ng/mg) were significantly higher than those in the surrounding liver tissues (1.77 ± 0.27 ng/mg); those in the control tissues were below the analytical range of the method used. The group II PLA2 mRNA was also significantly increased in the tumor tissues, compared with that in the surrounding liver tissues, whereas it was not detectable in th controls. This indicates that group II PLA2 in HCC is induced at the pretranslational level. 相似文献
13.
Kazuhito Hisatsune Takehiro Iguchi Yuji Haishima Norihiko Tamura Seiichi Kondo 《Microbiology and immunology》1993,37(2):143-147
The chemical properties of a lipopolysaccharide (LPS) isolated from a new O-antigenic form (O13) of Vibrio parahaemolyticus were investigated. The LPS contained glucose, galactose, L -glycero-D -manno-heptose and glucosamine. 2-Keto-3-deoxy-octonate (KDO) was not detected in the LPS by the periodate-thiobarbituric acid test (Weissbach's reaction) under conventional hydrolysis conditions. Instead, phosphorylated KDO (X1 and X2) was found in its strong-acid hydrolysate. This sugar composition was identical to that of V. parahaemolyticus O3, O5 and O11 LPS, indicating that, based on the sugar composition, O13 LPS belongs to Chemotype III to which O3, O5 and O11 belong. In addition, structural study demonstrated the presence of KDO 4-phosphate in its inner-core region. 相似文献
14.
Yuji Moriwaki Tetsuya Yamamoto Kei Yamaguchi Sumio Takahashi Kazuya Higashino 《Histochemistry and cell biology》1996,105(1):71-79
Tissues from male Wistar rats, fixed with 4% paraformaldehyde and embedded in paraffin, were studied with immunoperoxidase techniques using polyclonal antibodies raised against aldehyde oxidase or xanthine oxidase purified from rat liver. Immunohistochemical studies demonstrated that aldehyde oxidase-bearing cells were strongly stained in renal tubules, esophageal, gastric, intestinal and bronchial epithelium as well as liver cytoplasm. Weak but positive immunoreactivity was observed on the pulmonary alveolar epithelial cells, gastric glands and intestinal goblet cells. In contrast, it was demonstrated that cells with xanthine oxidase were strongly stained in renal tubules, esophageal, gastric, and small and large intestinal and bronchial epithelia etc. Positive immunostaining was also found in adrenal gland, skeletal muscle, spleen and cerebral hippocampus. Immunoreactivity againt aldehyde oxidase was not found in adrenal gland, spleen, mesentery or aorta, while immunoreactivity against xanthine oxidase was not found in mesentery or aorta. Although the significance of this ubiquitous and similar localization of aldehyde and xanthine oxidase seems unclear at present, these results may provide a clue as to the full understanding of the pathophysiological role of these oxidases in tissues. 相似文献
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John R. Silvius Yuji Saito Ronald N. McElhaney 《Archives of biochemistry and biophysics》1977,182(2):455-464
The regulation of the nature and quantity of the fatty acids produced in vivo by Acholeplasma laidlawii B in the presence of various exogenous fatty acids has been investigated. In the presence of exogenous medium- or long-chain fatty acids, the organism appears to reduce the amounts of de novo biosynthesized fatty acids in its cellular lipid pool by two distinct mechanisms: an excretion of biosynthesized fatty acids to the growth medium as free fatty acids, and a reduction in total de novo biosynthetic output. These two mechanisms do not suffice to maintain constant total membrane lipid levels, but they do appear to significantly moderate the effect of exogenous fatty acids on the level of membrane lipid. In the presence of short-chain fatty acids, total membrane lipid levels are not elevated. Exogenous fatty acids can cause shifts in the average chain length of de novo biosynthesized fatty acids; the magnitudes and directions of these shifts can be correlated with the specificity of the exogenous species for esterification to the 1- or the 2-position of the glycerol moiety of membrane glycerolipids. As the various endogenously synthesized fatty acids differ in their positional specificity for glycerolipid esterification, we propose that the competition of an exogenous species with significant specificity for a particular position with the endogenously derived fatty acids specific for that position can selectively depress the synthesis of such endogenously derived species, thereby altering the overall product spectrum of de novo fatty acid biosynthesis in vivo. 相似文献
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19.
Two kinds of ATP binding sites were found on the ATPase molecule in deoxycholic acid-treated sarcoplasmic reticulum. One was the catalytic site (1 mol/mol active site) and its affinity was high. Upon addition of Ca2+, all the ATP bound to the catalytic site disappeared at 75 mM KCl, while a significant amount of ATP remained bound to the site at 0–2 mM KCl. The latter binding was found to be due to the formation of a slowly exchanging enzyme-ATP complex, which is in equilibrium with phosphoenzyme + ADP. The other binding site was the regulatory one (1 mol/mol active site) and its affinity was low, changing only insignificantly upon addition of Ca2+. The ATP binding to the regulatory site shifted the equilibrium between the slowly exchanging complex and EP toward EP. 相似文献
20.
Two-dimensional nmr techniques have been carried out for the peak assignment of the spectrum of a somatostatin analog. Two-dimensional J-resolved spectroscopy simplified the rather broad and complicated spectrum to show the center of chemical shifts of each resonance and gave information on the coupling profiles. Another technique, two-dimensional spin-echo correlated spectroscopy, revealed the connectivities between protons which are correlated by weak spin–spin couplings. The combination of the results of these two complementary techniques made it possible for us to assign almost all peaks of the spectrum of the 11-residue somatostatin analog. 相似文献