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31.
Stabilization of the phosphorylated form of Bacillus subtilis DegU caused by degU9 mutation 总被引:1,自引:0,他引:1
Abstract A Bacillus subtilis response regulator, DegU9, carrying an amino acid alteration caused by the degU9 (Hy) mutation was partially purified, and phosphorylation and dephosphorylation of the protein was studied. The extent of phosphorylation was not as high as the level attained with wild-type DegU, but the DegU9-phosphate once formed was more stable than the wild-type DegU-phosphate. An in vivo study with a degU9 mutant showed that degS was necessary for the overproduction of exoproteases. These results suggest that phosphorylation is necessary for the mutant DegU9 to exert its effect and that the higher stability of phosphorylated DegU9 is responsible for the overproulation phenotype. 相似文献
32.
Safak Yalcin Hirohiko Kuratsune Koji Yamaguchi Teruo Kitani Koichi Yamanishi 《Microbiology and immunology》1994,38(7):587-590
Peripheral blood mononuclear cells collected from 13 patients with chronic fatigue syndrome and 13 healthy controls were analyzed for the presence of human herpesvirus 6 (HHV-6) DNA by variant-specific polymerase chain reaction and dot blot hybridization. HHV-6 DNA was detected in 7 of 13 (53%) patients, and of those 7 patients, 4 were positive for HHV-6 variant A DNA and 3 were for variant B. No HHV-6 DNA was detected in the controls. Serum antibody titers to the late antigen and antibody prevalence to the early antigen of HHV-6 were significantly higher in the patient group. These results suggest active replication of HHV-6 in patients with chronic fatigue syndrome. 相似文献
33.
34.
Naoyuki Nakahama Ryosuke Okano Yuichiro Nishimoto Yusuke Nakatani Asato Noishiki Naoki Ogawa 《Entomological Science》2023,26(2):e12545
Wetland biodiversity is currently declining on a global scale. Wetland biodiversity understanding is critical for determining the wetlands' conservation value. In this study, Macroplea Samouelle, 1819 (Coleoptera: Chrysomelidae) was discovered in Aomori Prefecture, Honshu Island, Japan. Only two Macroplea species have been recorded in Japan, M. japana (Jacoby, 1885) and M. mutica (Fabricius, 1792). Macroplea japana had been unrecorded for 60 years before being rediscovered in Honshu Island in 2022, and a single adult M. mutica female was discovered in Hokkaido Prefecture in 2003. The discovered individuals were concluded to be M. mutica based on morphological and molecular analyses. Although morphological differences were observed with the Eurasian M. mutica individuals, the male genitalia was nearly identical to M. mutica. For the molecular phylogenetic analysis based on COI and 28S sequences, Macroplea individuals in Japan were clustered with M. mutica on the Eurasian Continent. This is the first record of this species on Honshu Island (and the second in Japan), as well as the first record of adult males. This species would require conservation policies and additional distributional surveys. 相似文献
35.
Genetic transformation in Helicobacter pylori was investigated by using its chromosomal and plasmid DNAs. Six out of the eight strains exhibited the natural competence for incorporation of H. pylori chromosomal DNA, and all the strains incorporated the donor DNA efficiently by washing and concentrating the cells, with a glycerol solution. The much higher frequency of transformation was obtained in each strain by means of electroporation. Electroporation experiments were also conducted by use of the recombinant DNAs consisting of the H. pylori and Escherichia coli plasmids as the donors, and the occurrence of the homologous recombination was demonstrated between the incoming H. pylori plasmid-derived region and the corresponding region of the originally residing plasmid in H. pylori. 相似文献
36.
Shuhei Takatsuka Takeshi Kubota Yuta Kurashina Sho Kurihara Motoki Hirabayashi Masato Fujioka Hirotaka James Okano Hiroaki Onoe 《Biotechnology and bioengineering》2023,120(8):2371-2377
Adeno-associated virus (AAV)-based gene therapy holds promise as a fundamental treatment for genetic disorders. For clinical applications, it is necessary to control AAV release timing to avoid an immune response to AAV. Here we propose an ultrasound (US)-triggered on-demand AAV release system using alginate hydrogel microbeads (AHMs) with a release enhancer. By using a centrifuge-based microdroplet shooting device, the AHMs encapsulating AAV with tungsten microparticles (W-MPs) are fabricated. Since W-MPs work as release enhancers, the AHMs have high sensitivity to the US with localized variation in acoustic impedance for improving the release of AAV. Furthermore, AHMs were coated with poly-l -lysine (PLL) to adjust the release of AAV. By applying US to the AAV encapsulating AHMs with W-MPs, the AAV was released on demand, and gene transfection to cells by AAV was confirmed without loss of AAV activity. This proposed US-triggered AAV release system expands methodological possibilities in gene therapy. 相似文献
37.
Yoriko Masuda Satoshi Haramizu Kasumi Oki Koichiro Ohnuki Tatsuo Watanabe Susumu Yazawa Teruo Kawada Shu-ichi Hashizume Tohru Fushiki 《Journal of applied physiology》2003,95(6):2408-2415
Capsiate is a nonpungent capsaicin analog, a recently identified principle of the nonpungent red pepper cultivar CH-19 Sweet. In the present study, we report that 2-wk treatment of capsiate increased metabolic rate and promoted fat oxidation at rest, suggesting that capsiate may prevent obesity. To explain these effects, at least in part, we examined uncoupling proteins (UCPs) and thyroid hormones. UCPs and thyroid hormones play important roles in energy expenditure, the maintenance of body weight, and thermoregulation. Two-week treatment of capsiate increased the levels of UCP1 protein and mRNA in brown adipose tissue and UCP2 mRNA in white adipose tissue. This dose of capsiate did not change serum triiodothyronine or thyroxine levels. A single dose of capsiate temporarily raised both UCP1 mRNA in brown adipose tissue and UCP3 mRNA in skeletal muscle. These results suggest that UCP1 and UCP2 may contribute to the promotion of energy metabolism by capsiate, but that thyroid hormones do not. 相似文献
38.
A 19-kb CpG Island Associated with Single-minded Gene 2 in Down Syndrome Chromosomal Region 总被引:1,自引:0,他引:1
Osoegawa Kazutoyo; Okano Saishi; Kato Yasutake; Nishimura Yukinobu; Soeda Eiichi 《DNA research》1996,3(3):175-179
To help in isolating the genes involved in Down syndrome, wesought CpG islands in 4 Mb cosmid/PAC contigs spanning mostof the 21q.22.2 band using seven rare cutting enzymes. A strikingfeature was observed upstream of hSIM2 where at least 41 rare-cuttingsites were clustered within a 20-kb region. To investigate thestructure of the cluster, a cosmid containing hSIM2 was submittedto shotgun sequencing. Sequence analysis revealed that the clusterwas a long CpG island extending 19, 128 nucleotides which includesin the first and second exons of hSIM2. Taken together withour observation in which the CpG islands were concentrated within1.2 Mb around hSIM2, we propose that this region functions asan R-band, and the cluster provides a unique element for markingof DNA for the spatial and temporal expression of the hSIM2locus. 相似文献
39.
Podocytes outgrown from isolated glomeruli in vitro have failed to express fully differentiated in vivo phenotypes. In an
attempt to determine whether podocytes in metanephric culture accomplish terminal differentiation, as observed in vivo, we
investigated expression of their characteristic phenotypic features in rat metanephric organ cultures using immunohistochemistry
and electron microscopy. Rat metanephroi were harvested on embryonic day 12.5 and cultured on transmembrane filters for 9
days. Morphological examination revealed two maturation stages when the podocytes resembled those of the S-shaped body stage
and maturational stages of glomeruli in vivo. Electron microscopy revealed that, firstly podocytes lost their intercellular
contacts and, simultaneously, the tight junctions shifted into close proximity to cell bases, followed by foot process development.
Immunohistochemistry demonstrated that the tight junction protein, ZO-1, and specific podocytic markers, pp44, 5-1–6, podocalyxin
and vimentin were expressed in a cell maturity-dependent manner, as observed in newborn rat kidneys. Furthermore, glomerular
basement membrane components, collagen type IV and laminin, were expressed in the glomerular center. Our findings that cell
maturity-dependent expression of structural and functional phenotypes in podocytes in metanephric culture was the same as
that observed in developing kidneys in vivo indicate that podocyte differentiation during glomerulogenesis may be operated
by an intrinsic property, such as programmed cell fate. Furthermore, these highly differentiated podocytes in vitro may provide
clues that will help to establish a podocyte culture system.
Accepted: 26 February 1997 相似文献
40.
Teruo Yamashita Kenji Sakae Shinichi Kobayashi Yuichi Ishihara Takashi Miyake Agboatwalla Mubina Shin Isomura 《Microbiology and immunology》1995,39(6):433-435
Aichi virus was isolated in Vero cells from 5 (2.3%) of 222 Pakistani children with gastroenteritis but none was found in 91 healthy children. Aichi virus was also isolated from 5 (0.7%) of 722 Japanese travelers returned from tours to Southeast Asian countries and complained of gastrointestinal symptoms at the quarantine station of Nagoya International Airport in Japan. Of 5 Japanese travelers, 3 were returning from Indonesia, and 2 from Thailand or Malaysia. These results indicate that Aichi virus or a similar agent is endemic in Southeast Asian countries and is a cause of gastrointestinal symptoms in children in these areas or in Japanese travelers who visit there. 相似文献