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141.
A nuclear RNA fraction isolated from chick or calf liver, chick or calf kidney, and Rous sarcoma contains four (5.0S, 4.5S, 4.2S, 4.0S), five (5.0S, 4.5S, 4.3S, 4.2S, 4.0S), and three (5.0S, 4.2S, 4.0S) species of RNA, respectively. All RNAs except 4.2S, 4.0S, and the sarcoma 5.0S RNA are capable of stimulating significantly RNA synthesis in vitro with chromatin from the corresponding tissue as template. 5.0S RNAs from the normal tissues of the same animal are also effective in stimulating the RNA polymerization reactions with chromatin of the heterologous tissues but to lesser extent. Available evidence will show that the stimulation may presumably be due to specific structures of RNA molecules which have a high content of uridylic acid. 相似文献
142.
A new bacteriophage of low guanine plus cytosine (GC) content for Methanomonas methylovora has been isolated. Phage deoxyribonucleic acid contained 32 to 35% GC. 相似文献
143.
Takashima Natsuki Ishino Sonoko Oki Keisuke Takafuji Mika Yamagami Takeshi Matsuo Ryotaro Mayanagi Kouta Ishino Yoshizumi 《Extremophiles : life under extreme conditions》2019,23(1):161-172
Extremophiles - DNA polymerase D (PolD), originally discovered in Pyrococcus furiosus, has no sequence homology with any other DNA polymerase family. Genes encoding PolD are found in most of... 相似文献
144.
"Candidatus Accumulibacter phosphatis" is considered a polyphosphate-accumulating organism (PAO) though it has not been isolated yet. To reveal the denitrification ability of this organism, we first concentrated this organism by flow cytometric sorting following fluorescence in situ hybridization (FISH) using specific probes for this organism. The purity of the target cells was about 97% of total cell count in the sorted sample. The PCR amplification of the nitrite reductase genes (nirK and nirS) from unsorted and sorted cells was performed. Although nirK and nirS were amplified from unsorted cells, only nirS was detected from sorted cells, indicating that "Ca. Accumulibacter phosphatis" has nirS. Furthermore, nirS fragments were cloned from unsorted (Ba clone library) and sorted (Bd clone library) cells and classified by restriction fragment length polymorphism analysis. The most dominant clone in clone library Ba, which represented 62% of the total number of clones, was not found in clone library Bd. In contrast, the most dominant clone in clone library Bd, which represented 59% of the total number of clones, represented only 2% of the total number of clones in clone library Ba, indicating that this clone could be that of "Ca. Accumulibacter phosphatis." The sequence of this nirS clone exhibited less than 90% similarity to the sequences of known denitrifying bacteria in the database. The recovery of the nirS genes makes it likely that "Ca. Accumulibacter phosphatis" behaves as a denitrifying PAO capable of utilizing nitrite instead of oxygen as an electron acceptor for phosphorus uptake. 相似文献
145.
G. Wilson Fernandes Yumi Oki Michel Stórquio Belmiro Fernando M. Resende Ary Corrêa Junior João Lucio de Azevedo 《Arthropod-Plant Interactions》2018,12(3):329-337
The tropics are known for their high diversity of plants, animals, and biotic interactions, but the role of the speciose endophytic fungi in these interactions has been mostly neglected. We report a unique interaction among plant sex, bees, and endophytes on the dioecious shrub, Baccharis dracunculifolia (Asteraceae). We assessed whether there was an association between resin collection by bees and fungal endophytes considering the host plant sex. We hypothesized that resin collection by the Africanized honey bee, Apis mellifera L. (Apidae) could favor the entry of endophytes in B. dracunculifolia. Specifically, we tested the hypotheses that (1) bees damage the leaf buds of female and male plant at different proportions; (2) damage on leaf buds increases the richness of endophytic fungi; (3) endophyte richness differs between female and male plants; and (4) in vitro growth of endophytes depends on the sex of the plant individual from which the resin was extracted. Endophyte richness and proportion of leaf bud damage did not vary between the plant sexes. However, species similarity of endophytes between female and male plants was 0.33. Undamaged leaf buds did not show culturable endophytes, with all fungi exclusively found in damaged leaf buds. Endophyte composition changed with the plant sex. The endophytes exclusively found in female plants did not develop in the presence of male resin extract. These findings highlight that resin collection by A. mellifera for propolis production favors the entry of endophytic fungi in B. dracunculifolia. Additionally, endophyte composition and growth are influenced by plant sex. 相似文献
146.
Tear proteins were detected by polyacrylamide gel electrophoresis in the vole, Microtus arvalis. The tear proteins were separated to 6 to 8 bands and the bands were divided to three regions on the anodic side. In the adult male vole, a male specific band (Vtp-1) was detected in the first region. The first region of adult female and immature voles contained two specific bands (Vtp-2, 3). In the castrated adult males or adult males injected with estrogen, the male specific hand, Vtp-1, disappeared and Vtp-2 and 3 bands appeared. In all castrated voles, the Vtp-1 band appeared and Vtp-2 and 3 bands disappeared after the administration of testosterone. Thus, sex hormone-dependent proteins are present in vole tears. 相似文献
147.
Kazuhiro Takeuchi Ikuro Maruyama Sinichi Yamamoto Toshimichi Oki Yukihiro Nagata 《In vitro cellular & developmental biology. Animal》1991,27(9):720-724
Summary In the present study we have established a pure monolayer culture system of human fallopian tube epithelial cells. The cells
were isolated using collagenase digestion, and were cultured in Medium 199 supplemented with 15% fetal bovine serum. The epithelial
cells derived from primary and secondary culture were characterized using immunocytochemical staining and electron microscopy.
The cells continued to grow for 2 to 3 wk once the monolayer culture of the cells was established. It is currently possible
to maintain the cultures until the third generation. Proliferation of these cells was enhanced by epidermal growth factor
but not by basic-fibroblast growth factor, insulin, transferrin, estradiol-17β, or progesterone. This culture system offers a good model for determining characteristics of the tubal epithelium and would
permit effective study of co-culture with embryos. 相似文献
148.
T Komiyama T Oki T Inui T Takeuchi H Umezawa 《Biochemical and biophysical research communications》1978,82(1):188-195
In the course of studies on the metabolism of a new antitumor anthracycline antibiotic, aclacinomycin A, the new keto reductase which catalyzes the reduction of keto group of L-cinerulose of aclacinomycin A to L-rhodinose was found in rat liver microsomal membrane. The enzyme requires NADH for the reduction and showed optimum pH at 7.0. Km value for aclacinomycin A, 2.1 × 10?5 M and the concentration of NADH need to half maximal activity, 6.2 × 10?5 M were obtained. The activity was potently inhibited by detergents, such as Triton X-100, sodium deoxycholate and sodium dodecyl sulfate. 相似文献
149.
We show here novel intracellular Ca2+ oscillation in v-K-ras-transformed NIH3T3 cells induced by mitogenic peptide hormones, bradykinin and bombesin, as well as fetal calf serum. Induction of the Ca2+ oscillation is strongly correlated with the malignant properties and inversely with PKC activities in vitro and in vivo. These results suggest that the mitogen-induced Ca2+ oscillation is negatively regulated by PKC, which modulates Ca2+ influx in v-K-ras-transformed NIH3T3 cells. 相似文献
150.