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71.
Thi Hai Yen Tran Aya Fukuda Shiho Aizawa Phuong Linh Bui Yohei Hayashi Ken Nishimura Koji Hisatake 《Biochemistry and Biophysics Reports》2018
Generation of induced pluripotent stem cells (iPSCs) with naive pluripotency is important for their applications in regenerative medicine. In female iPSCs, acquisition of naive pluripotency is coupled to X chromosome reactivation (XCR) during somatic cell reprogramming, and live cell monitoring of XCR is potentially useful for analyzing how iPSCs acquire naive pluripotency. Here we generated female mouse embryonic stem cells (ESCs) that carry the enhanced green fluorescent protein (EGFP) and humanized Kusabira-Orange (hKO) genes inserted into an intergenic site near either the Syap1 or Taf1 gene on both X chromosomes. The ESC clones, which initially expressed both EGFP and hKO, inactivated one of the fluorescent protein genes upon differentiation, indicating that the EGFP and hKO genes are subject to X chromosome inactivation (XCI). When the derived somatic cells carrying the EGFP gene on the inactive X chromosome (Xi) were reprogrammed into iPSCs, the EGFP gene on the Xi was reactivated when pluripotency marker genes were induced. Thus, the fluorescent protein genes inserted into an intergenic locus on both X chromosomes enable live cell monitoring of XCI during ESC differentiation and XCR during reprogramming. This is the first study that succeeded live cell imaging of XCR during reprogramming. 相似文献
72.
Characterization of Fusarium oxysporum β-1,6-Galactanase, an Enzyme That Hydrolyzes Larch Wood Arabinogalactan 下载免费PDF全文
Tatsuji Sakamoto Yuya Taniguchi Shiho Suzuki Hideshi Ihara Haruhiko Kawasaki 《Applied microbiology》2007,73(9):3109-3112
A type II arabinogalactan-degrading enzyme (FoGal1) was purified from Fusarium oxysporum 12S, and the corresponding cDNA was isolated. FoGal1 had high similarity to enzymes of glycoside hydrolase family 5. Treatment of larch wood arabinogalactan with the recombinant enzyme indicated that FoGal1 is a β-1,6-galactanase that preferentially debranches β-1,6-galactobiose from the substrate. 相似文献
73.
Koji Kashima Yoshikazu Yuki Mio Mejima Shiho Kurokawa Yuji Suzuki Satomi Minakawa Natsumi Takeyama Yoshiko Fukuyama Tatsuhiko Azegami Takeshi Tanimoto Masaharu Kuroda Minoru Tamura Yasuyuki Gomi Hiroshi Kiyono 《Plant cell reports》2016,35(3):667-679
Key message
The first Good Manufacturing Practices production of a purification-free rice-based oral cholera vaccine (MucoRice-CTB) from transgenic plants in a closed cultivation system yielded a product meeting regulatory requirements.Abstract
Despite our knowledge of their advantages, plant-based vaccines remain unavailable for human use in both developing and industrialized countries. A leading, practical obstacle to their widespread use is producing plant-based vaccines that meet governmental regulatory requirements. Here, we report the first production according to current Good Manufacturing Practices of a rice-based vaccine, the cholera vaccine MucoRice-CTB, at an academic institution. To this end, we established specifications and methods for the master seed bank (MSB) of MucoRice-CTB, which was previously generated as a selection-marker-free line, evaluated its propagation, and given that the stored seeds must be renewed periodically. The production of MucoRice-CTB incorporated a closed hydroponic system for cultivating the transgenic plants, to minimize variations in expression and quality during vaccine manufacture. This type of molecular farming factory can be operated year-round, generating three harvests annually, and is cost- and production-effective. Rice was polished to a ratio of 95 % and then powdered to produce the MucoRice-CTB drug substance, and the identity, potency, and safety of the MucoRice-CTB product met pre-established release requirements. The formulation of MucoRice-CTB made by fine-powdering of drug substance and packaged in an aluminum pouch is being evaluated in a physician-initiated phase I study.74.
Obata M Hirohara S Sharyo K Alitomo H Kajiwara K Ogata S Tanihara M Ohtsuki C Yano S 《Biochimica et biophysica acta》2007,1770(8):1204-1211
75.
Tetsuya Yabutani Mami Tsujimoto Shunsuke Ohira Shiho Shimizu Hideo Nakano 《Bioscience, biotechnology, and biochemistry》2017,81(7):1456-1459
A Gram-positive bacterium Lentzea sp. 7887 hydroxylates a cyclosporine derivative FR901459 into AS1837812 (9-hydroxide), which is an important intermediate of candidate drugs that target the hepatitis C virus. We screened a UV-induced mutant, named M-1, which showed about 1.2-fold higher conversion yields, 2-fold higher substrate concentrations (3.69 mM), and 2.5-fold higher yield per unit volume than the wild-type strain. 相似文献
76.
Given the reported degraded nature of DOC in the Rio Negro, and low oxygen, pH, and bacterial riverine levels, we hypothesized: (1) DOC would have strong humic and fulvic acid fluorescence signals with high aromaticity and large mean molecular weight; and (2) photo-oxidation rates would be slow, and reactive oxygen species (ROS) concentrations low, producing no oxidative stress in biota. We surveyed the environment and properties of DOC and explored DOC photo-oxidation and fish sensitivity to DOC products. DOC properties were investigated using absorption and fluorescence indices and parallel factor analysis (PARAFAC) of excitation–emission matrices. ROS concentrations were measured spectrophotometrically. A native fish, Hemigrammus levis, was exposed to photo-oxidizing DOC and its tissues (brain, gill, liver) assayed for changes in antioxidant and biotransformation enzymes. With respect to our hypotheses, (1) DOC was highly terrigenous, with high SAC340 values (aromaticity), high capacity to produce ROS, and high tryptophan-like fluorescence (bacterial, autochthonous signal); (2) photo-oxidation rates were appreciable, while products were related to mean UV-radiation levels (total radiation was constant). ROS levels were often higher than freshwater averages, yet fish experienced no oxidative stress. Results suggest photo-oxidation influences patterns in C-cycling, bacterial production and community dynamics between wet and dry seasons. 相似文献
77.
Cryptosporidium parvum is an intracellular protozoan parasite belonging to the phylum Apicomplexa, and a major cause of waterborne gastroenteritis throughout the world. Invasive zoites of apicomplexan parasites, including C. parvum, are thought to have characteristic organelles on the apical apex; however, compared with other parasites, the cytoskeletal ultrastructure of C. parvum zoites is poorly understood. Thus, in the present study, we ultrastructurally examined C. parvum sporozoites using electron microscopy to clarify the framework of invasive stages. Consequently, at the apical end of sporozoites, 3 apical rings and an electron-dense collar were seen. Two thick central microtubules were seen further inside sporozoites and extended to the posterior region. Using anti-alpha and -beta tubulin antibodies generated from sea urchin and rat brain, both antibodies cross-reacted at the apical region of sporozoites in immunofluorescent morphology. The molecular mass of C. parvum alpha tubulin antigen was 50 kDa by Western blotting and the observed apical cytoskeletal structures were shown to be composed of alpha tubulin by immunoelectron microscopy. These results suggested that C. parvum sporozoites were clearly different in their cytoskeletal structure from those of other apicomplexan parasites. 相似文献
78.
CONTRIBUTION OF MULTIPLE ISOLATING BARRIERS TO REPRODUCTIVE ISOLATION BETWEEN A PAIR OF PHYTOPHAGOUS LADYBIRD BEETLES 总被引:1,自引:0,他引:1
Kei W. Matsubayashi Haruo Katakura 《Evolution; international journal of organic evolution》2009,63(10):2563-2580
Reproductive isolation between species may often be attained by multiple isolating barriers, but the components are rarely studied in animal taxa. To elucidate the nature of multiple isolating barriers, we quantified the strength of three premating barriers, including ecologically based ones (seasonal, habitat, and sexual), two postmating–prehatching barriers (reduced egg hatchability and conspecific sperm precedence [CSP]), and one posthatching barrier, including four components of F1 hybrid reduced fitness, between two phytophagous ladybird beetles, Henosepilachna vigintioctomaculata and H. pustulosa . We detected five positive barriers (habitat isolation, sexual isolation, reduced egg hatchability, CSP, and reduced egg hatchability in backcrosses of F1 hybrids). None of these barriers entirely prevents gene exchange when it acts alone, but jointly they generate nearly complete reproductive isolation even between sympatric populations. Host fidelity contributed most strongly to reproductive isolation by reducing interspecific hybridization through several important types of ecological isolation, including microspatial, habitat, and seasonal isolation. The existence of multiple isolating barriers likely helps keep reproductive isolation stable and robust, by complementing changes in the strength of leaky barriers. This complementarity of multiple isolating barriers yields the concept of robustness of reproductive isolation, which is important when considering the long-term maintenance of species boundaries in coexisting species pairs. 相似文献
79.
80.
Nagaaki Sato Makoto Jitsuoka Shiho Ishikawa Keita Nagai Hiroyasu Tsuge Makoto Ando Osamu Okamoto Hisashi Iwaasa Akira Gomori Akane Ishihara Akio Kanatani Takehiro Fukami 《Bioorganic & medicinal chemistry letters》2009,19(6):1670-1674
Novel imidazoline derivatives were discovered to be potent neuropeptide Y Y5 receptor antagonists. High-throughput screening of Merck sample collections against the human Y5 receptor resulted in the identification of 2,4,4-triphenylimidazoline (1), which had an IC50 of 54 nM. Subsequent optimization led to the identification of several potent derivatives. 相似文献