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961.
When urinary bladder epithelia of rats were grown in association with fetal urogenital sinus mesenchyme, prostatic morphogenesis was induced. The epithelial proteins were examined by HPLC fractionation followed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE). More than 500 bands of silver-stained epithelial proteins were analyzed. The glandular epithelia induced from both adult and fetal bladder epithelia lost all of the 7 bladder-specific bands (BE 1–7) in most recombinants and expressed a number of prostate-specific bands. Among the 18 bands commonly found in all prostatic lobes, 13 (PE 4, 7–18) were constantly and 3 (PE 1–3) were sporadically detected, while the other 2 (PE 5 and 6) bands were not detected when the adult epithelium was used in recombination. Among the 7 prostatic lobe-specific bands (vPE 14, dPE 1–3), most of them were detected when the fetal epithelium was used, while few of them when the adult epithelium was used. These results demonstrate that prostatic morphogenesis induced in the bladder epithelium was associated with most of biochemical features of prostate. In addition to the biochemical study, histological examination revealed that the prostatic differentiation was more complete in the fetal bladder epithelium than the adult one. 相似文献
962.
Lectin activity, agglutinating sheep erythrocytes, was associated with parasporal inclusion proteins from a Lepidoptera-specific
isolate of Bacillus thuringiensis serovar galleriae (H5ab). The activity was generated when parasporal inclusions were solubilized in an alkaline condition. Proteolytic processing
was not required for generation of the lectin activity; the activity level was not affected by the presence/absence of the
three proteases (trypsin, chymotrypsin, and proteinase K). SDS-PAGE analysis revealed that (1) alkali-solubilized parasporal
inclusion proteins consisted of two major components of 130 kDa and 65 kDa, and (2) proteinase K treatment of alkali-solubilized
proteins yielded a single major protein of 60 kDa. Lectin activity of our isolate was strongly inhibited by preincubation
with D-mannose, but not with the six other monosaccharides: D-galactose, D-glucose, L-fucose, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, and N-acetylneuraminic acid. In contrast, D-mannose did not inhibit the in vivo larvicidal activity of the proteins against the silkworm, Bombyx mori.
Received: 21 February 2002 / Accepted: 28 March 2002 相似文献
963.
The mutagenicities of aniline, -toluidine and yellow OB were demonstrated only in the presence of the β-carboline compound, norharman. The effect of norharman increased linearly with increase in the amount of S-9. The mutagenicity of 4-dimethylaminoazobenzene was greatly enhanced by the presence of norharman, and again dose-dependency on the amount of S-9 was observed. In the presence of a large amount of S-9, norharman caused several fold enhancement of the mutagenicities of -2-fluorenylacetamide, benzo(a)-pyrene, and 1,4-dimethyl-3-amino-5-pyrido(4,3) indole, isolated from a tryptophan pyrolysate. However, norharman suppressed the mutagenicities of these compounds in the presence of a small amount of S-9. The mutagenicity of kaempferol, a flavonoid, was inhibited by norharman with either a large or small amount of S-9. 相似文献
964.
965.
Toshio Suzuki Naoya Kasai Ryoichi Yamamoto Noshi Minamiura 《Applied microbiology and biotechnology》1993,40(2-3):273-278
A bacterium that assimilates (S)-3-chloro-1,2-propanediol [monochlorohydrin (MCH)] was isolated from soil by enrichment culture. The bacterium was identified as Pseudomonas sp. by taxonomic studies. The strain grew in a medium containing racemic MCH as a source of carbon and degraded (S)-MCH stereoselectively, liberating chloride ions. The residual isomer was the (R)-form [99.5% enantiomeric excess (ee)], which was obtained from the racemate in a final yield of 36% by using this strain. Subsequently, highly optically active (R)-glycidol (GLD) (99.3% ee) was prepared from the (R)-MCH obtained by reaction in alkaline solution. The cell-free extracts of the cells had both dehalogenating and epoxide-opening activities, which converted various halohydrins to the corresponding epoxides and epoxides to the corresponding diols, respectively.
Correspondence to: T. Suzuki 相似文献
966.
Osao Adachi Thuy M. Nguyen Roque A. Hours Naoya Kataoka Kazunobu Matsushita Yoshihiko Akakabe 《Bioscience, biotechnology, and biochemistry》2020,84(8):1745-1747
ABSTRACT
Gluconobacter frateurii CHM 43 have D-mannitol dehydrogenase (quinoprotein glycerol dehydrogenase) and flavoprotein D-fructose dehydrogenase in the membranes. When the two enzymes are functional, D-mannitol is converted to 5-keto-D-fructose with 65% yield when cultivated on D-mannitol. 5-Keto-D-fructose production with almost 100% yield was realized with the resting cells. The method proposed here should give a smart strategy for 5-keto-D-fructose production. 相似文献
967.
Yamaya Tomoyuki; Tanno Hiromi; Hirose Naoya; Watanabe Sachiko; Hayakawa Toshihiko 《Plant & cell physiology》1995,36(7):1197-1204
When rice seedlings, after the growth for 26 days in water alone,were transferred to nutrient medium contained 1 mM NH4Cl, thelevel of NADH-dependent glutamate synthase (GOGAT) protein andthe activity of the enzyme increased more than 10-fold in root,but not in shoots. Both the level of the protein and the activityreached a maximum within 24 h. NH4Cl was effective at concentrationsas low as 50 µM. A supply of either 1 mM NaNO3 or 0.5mM NH4NO3 also caused such increases, but NHa4Cl was most effective.A supply of glutamine or glutamate was less effective. The increasewas specific to NADH-GOGAT and little change was observed inthe levels of ferredoxin-GOGAT and glutamine synthetase isoproteinsin roots. These inducible increases in the levels of NADH-GOGATprotein and in its activity were greater in the root-tip regionthan at the base of the root. Both 6-methylpurine and cycloheximidecompletely inhibited the effects of NH4Cl. Moreover, the mRNAfor NADH-GOGAT in rice roots accumulated markedly within 12h of the start of a supply of NH4Cl. A possible role for therapid response of NADH-GOGAT to a supply of NH4C1 is discussed. (Received May 18, 1995; Accepted July 10, 1995) 相似文献
968.
Takashi Nobusawa Misaki Kamei Hiroaki Ueda Naoya Matsushima Hiroshi Yamatani Makoto Kusaba 《Plant physiology》2021,186(1):767
The cytochrome P450 CYP78A5/KLUH in Arabidopsis thaliana is predicted to be involved in the synthesis of a mobile signal molecule that has a pleiotropic function that is distinct from classical phytohormones. CYP78A5 has five close relatives in Arabidopsis. We first investigated their functions, focusing on the plastochron, leaf size, and leaf senescence. Our analyses revealed that CYP78A5 and CYP78A7 are involved in the plastochron and leaf size, and CYP78A6 and CYP78A9 are involved in leaf senescence. Complementation analyses using heterologous promoters and expression analyses suggested that CYP78A isoforms have a common biochemical function and are functionally differentiated via organ-specific expression. The altered meristem program1 (amp1) carboxypeptidase mutant shows a phenotype very similar to that of the cyp78a5 mutant. Complementation analyses using boundary and organizing center-specific promoters suggested that both CYP78A5 and AMP1 act in a non-cell-autonomous manner. Analyses of multiple cyp78a mutants and crosses between cyp78a and amp1 mutants revealed that AMP1/LIKE AMP1 (LAMP1) and CYP78A isoforms regulate plastochron length and leaf senescence in the same genetic pathway, whereas leaf size is independently regulated. Furthermore, we detected feedback regulation between CYP78A6/CYP78A9 and AMP1 at the gene expression level. These observations raise the possibility that AMP1 and CYP78A isoforms are involved in the synthesis of the same mobile signal molecule, and suggest that AMP1 and CYP78A signaling pathways have a very close, albeit complex, functional relationship.ALTERED MERISTEM PROGRAM1 and isoforms of the cytochrome P450 CYP78A regulate plastochron and leaf senescence in non-cell-autonomous/organ-specific manners, and have a close, albeit complex, and functional relationship. 相似文献