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11.
Kazuaki Manabe Mitsuyoshi Morii Masaru Honjo Masaharu Ohoka Kouichiro Fushimi Akiko Sawakura 《Bioscience, biotechnology, and biochemistry》2013,77(8):2261-2267
Bacillus subtilis 1A20 transformed with a hybrid plasmid, pNP150, to which a DNA fragment from Bacillus amyloliquefaciens F was attached, produced a large amount of a neutral protease. To identify the origin of the gene specifying this neutral protease, neutral proteases from B. amyloliquefaciens F, B. subtilis NP58 (a derivative of Marburg 6160), and B. subtilis 1A20 transformed with pNP150 were purified. We investigated their immunological properties and primary structures.The proteases from these two species were indistinguishable by chromatography, but they were distinguishable from each other by SDS-polyacrylamide gel electrophoresis and double immunodiffusion. Amino acid sequencing of these two proteases by Edman degradation showed that there were four substitutions in the 20-residue amino acid sequence from the N-termini.Neutral protease from the transformant had the same immunological characteristics and N-terminal amino acid sequence as that from B. amyloliquefaciens. These results meant that the gene in question was derived from a gene specifying the neutral protease in this bacterium. 相似文献
12.
Hiromichi Kato Mitsuyoshi Yamamoto Masao Fujimaki 《Bioscience, biotechnology, and biochemistry》2013,77(6):939-948
Degradation mechanisms of d-fructose by the interaction with amino acids or organic acids in aqueous solution at initial pH 5.5 heated at 100°C were investigated and a substantial difference in mechanisms between fructose degradation and glucose-glycine reaction was presented. d-Fructose browned more intensely than did d-glucose in lower concentration of glycine and/or in earier stage of reaction period. By catalytic action of carboxylate anions without any condensation with amino groups, d-fructose was decomposed to 3-deoxy-d-erythrohexosulose, 5-(hydroxymelhyl)-2-furaldehyde, and a less amount of pyruval-dehyde through caramelization. It was considered that the main path of fructose degradation was 1,2-enolization but 2,3-enolization would also occur to a little extent. 相似文献
13.
Asadullah Azam Yasuhisa Kunimi Maki N. Inoue Madoka Nakai 《Applied Entomology and Zoology》2016,51(3):479-488
14.
Yoichiro?OkuboEmail author Osamu?Motohashi Norisuke?Nakayama Ken?Nishimura Rika?Kasajima Yohei?Miyagi Manabu?Shiozawa Emi?Yoshioka Masaki?Suzuki Kota?Washimi Kae?Kawachi Madoka?Nito Yoichi?Kameda Tomoyuki?Yokose 《Diagnostic pathology》2016,11(1):128
Background
As the World Health Organization grading system for gastroenteropancreatic-neuroendocrine tumors (GEP-NETs) may not always correlate with tumor progression, it is imperative that other independent predictors of tumor progression be established. To identify such predictors, we conducted a retrospective histopathological study of hindgut NETs, obtained from endoscopic procedures, and used statistical analyses to evaluate predictive factors.Methods
We first obtained clinicopathological data of cases of hindgut NETs. Tissue sections from tumor samples were prepared and subjected to pathological examination. In particular, we calculated the microvessel density (MVD) and lymphatic microvessel density (LMVD) values, and performed appropriate statistical analyses.Results
A total of 42 cases of hindgut NETs were selected for the study, 41 from the rectum and 1 from the sigmoid colon. Based on the Ki-67 labeling index, 34 cases were classified as NET G1 tumors and 8 as NET G2 tumors. MVD values ranged from 1.4/mm2 to 73.9/mm2 and LMVD values from 0/mm2 to 22.9/mm2. MVD and LMVD were identified as risk factors for venous and lymphatic invasion of hindgut NETs. Moreover, MVD positively correlated with the maximum diameter of the tumor.Conclusions
Tumor progression of NETs may cause angiogenesis and lymphangiogenesis, via an unknown mechanism, as well as lymphovascular invasion. Angiogenesis likely plays an important role in occurrence and progression in the initial phase of hindgut NETs.15.
Germain H Houde J Gray-Mitsumune M Sawasaki T Endo Y Rivoal J Matton DP 《FEBS letters》2007,581(26):5137-5142
Solanum chacoense ovule receptor kinase 28 (ScORK28) was found among 30 receptor kinases from an ovule cDNA library enriched for weakly expressed mRNAs. This LRR-RLK displayed high level of tissue specificity at the RNA and protein levels and was predominantly expressed in female reproductive tissues. Protein expression analyses in planta revealed that ScORK28 was N-glycosylated and ScORK28::GFP fusion analyses showed that it was localized at the plasma membrane. Bacterial expression of ScORK28 catalytic domain followed by kinase activity assays revealed that ScORK28 is an active Mg2+-dependent protein kinase and that the juxtamembrane domain is necessary for kinase activity. 相似文献
16.
A simple method to disperse eggs from lepidopteran scalelike egg masses and to observe embryogenesis
Various insect species lay tiny, thin- and soft-shelled eggs in a connected “egg mass”. Especially in several lepidopteran species, the structure of such clustered eggs is covered with complicated scale-like secretion, which has so far prevented analysis of individual embryos. However, few studies on methods to disperse egg clusters of such insects and to compare different methods have been carried out. To overcome these problems, we developed methods to separate egg masses into individual eggs, using two Tortricidae pests, Homona magnanima Diakonoff and Adoxophyes honmai Yasuda (Lepidoptera: Tortricidae). The eggs were successfully separated from each other using potassium hydroxide and sodium hypochlorite. Although the separated eggs no longer continued their embryogenesis, fixation with heptane–paraformaldehyde, permeabilization with heptane–methanol, and staining with several dyes enabled easy observation of embryogenesis. This protocol is expected to be applicable to other insect taxa and will facilitate further morphological and genetic studies in insects that lay egg masses. 相似文献
17.
Structural and biochemical analyses of hemimethylated DNA binding by the SeqA protein 总被引:1,自引:1,他引:0
Fujikawa N Kurumizaka H Nureki O Tanaka Y Yamazoe M Hiraga S Yokoyama S 《Nucleic acids research》2004,32(1):82-92
The Escherichia coli SeqA protein recognizes the 11 hemimethylated G-mA-T-C sites in the oriC region of the chromosome, and prevents replication over-initiation within one cell cycle. The crystal structure of the SeqA C-terminal domain with hemimethylated DNA revealed the N6-methyladenine recognition mechanism; however, the mechanism of discrimination between the hemimethylated and fully methylated states has remained elusive. In the present study, we performed mutational analyses of hemimethylated G-mA-T-C sequences with the minimal DNA-binding domain of SeqA (SeqA71–181), and found that SeqA71–181 specifically binds to hemimethylated DNA containing a sequence with a mismatched mA:G base pair [G-mA(:G)-T-C] as efficiently as the normal hemimethylated G-mA(:T)-T-C sequence. We determined the crystal structures of SeqA71–181 complexed with the mismatched and normal hemimethylated DNAs at 2.5 and 3.0 Å resolutions, respectively, and found that the mismatched mA:G base pair and the normal mA:T base pair are recognized by SeqA in a similar manner. Furthermore, in both crystal structures, an electron density is present near the unmethylated adenine, which is only methylated in the fully methylated state. This electron density, which may be due to a water molecule or a metal ion, can exist in the hemimethylated state, but not in the fully methylated state, because of steric clash with the additional methyl group. 相似文献
18.
Absorption of acylated anthocyanins in rats and humans after ingesting an extract of Ipomoea batatas purple sweet potato tuber 总被引:3,自引:0,他引:3
Harada K Kano M Takayanagi T Yamakawa O Ishikawa F 《Bioscience, biotechnology, and biochemistry》2004,68(7):1500-1507
We evaluated the absorbability of anthocyanins in humans and rats administered with a beverage prepared from an extract of the tuber of purple sweet potato (Ipomoea batatas Cultivar Ayamurasaki), or with an anthocyanin concentrate. Two major anthocyanin components, cyanidin 3-O-(2-O-(6-O-(E)-caffeoyl-beta-D-glucopyranosyl)-beta-D-glucopyranoside)-5-O-beta-D-glucopyranoside) and peonidin 3-O-(2-O-(6-O-(E)-caffeoyl-beta-D-glucopyranosyl)-beta-D-glucopyranoside)-5-O-beta-D-glucopyranoside), were detected in the plasma and urine of both rats and humans by HPLC or liquid chromatography/mass spectrometry (LC/MS). The plasma concentration of anthocyanins in humans reached a maximum 90 minutes after ingestion, and the recovery of anthocyanins in the urine was estimated as 0.01-0.03%. These results indicate that acylated anthocyanins could be selectively absorbed after ingesting food. 相似文献
19.
Komoda T Kishi M Abe N Sugiyama Y Hirota A 《Bioscience, biotechnology, and biochemistry》2004,68(4):903-908
Three novel lipoxygenase inhibitors, tetrapetalone B (2, C(28)H(35)NO(9)), C (3, C(26)H(34)NO(8)), and D (4, C(28)H(36)NO(10)), were isolated from a culture broth of Streptomyces sp. USF-4727 that produced a lipoxygenase inhibitor tetrapetalone A (1) simultaneously. Each chemical structure was revealed by spectroscopic evidence, this suggests that these three compounds are structurally related to 1. They had a tetracyclic skeleton and a beta-D-rhodinosyl moiety. Tetrapetalone B, C, and D inhibited soybean lipoxygenase with IC(50): 320, 360, and 340 microM respectively. 相似文献
20.
Changes in oligosaccharide expression on plasma membrane of the mouse oocyte during fertilisation and early cleavage 总被引:3,自引:0,他引:3
Kitamura K Suganuma N Takata K Matsuyama K Goto J Furuhashi M Kanayama N 《Zygote (Cambridge, England)》2003,11(2):183-189
It has been reported that various structural and functional changes occur on the surface of the plasma membrane of the ovum and embryo during fertilisation and cleavage in preparation for implantation. Glycoproteins are thought to be one of the factors in cell attachment. Thus, we investigated the changes in glycoprotein expression on the cell surface membrane of the mouse embryo by using lectins. Among seven types of lectin (ConA, WGA, UEA-I, MPA, LCA, DBA and PNA), the fluorescent intensities of ConA and WGA markedly increased from unfertilised ova to blastocysts. By quantitative analysis using immuno-scanning electron microscopy, the numbers of ConA-gold particles were small until 4-cell cleavage, but increased significantly at the blastocyst stage. In contrast, an increased number of WGA-gold particles was detected even at the 4-cell stage, and this increase continued to the blastocyst stage. From the above observations, we conclude that the numbers of sugar chains bound to both ConA andWGA increases with blastocyst formation and earlier expression is observed with WGA. The present study dearly shows that glycoproteins on the cell membrane surface of the mouse embryo quantitatively increase at the time of implantation, and the possibility has been indicated that glycoproteins are involved in intercellular recognition and adhesion between the embryo and endometrial epithelium. 相似文献