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601.
Water molds of the genus Phytophthora include many plant pathogens responsible for epidemics such as potato blight and sudden oak death, causing global economic damages. Sexual reproduction is of biological importance in Phytophthora and has been believed to be stimulated by unknown endogenous factors named a hormones. We describe here the chemical characterization of a Phytophthora mating hormone, a1, which was obtained from approximately 2 tons of culture fluid of one mating type of a species and which induced sexual spores on the counter-mating type at a nanogram level.  相似文献   
602.
The gene for the human platelet alpha 2-adrenergic receptor has been cloned with oligonucleotides corresponding to the partial amino acid sequence of the purified receptor. The identity of this gene has been confirmed by the binding of alpha 2-adrenergic ligands to the cloned receptor expressed in Xenopus laevis oocytes. The deduced amino acid sequence is most similar to the recently cloned human beta 2- and beta 1-adrenergic receptors; however, similarities to the muscarinic cholinergic receptors are also evident. Two related genes have been identified by low stringency Southern blot analysis. These genes may represent additional alpha 2-adrenergic receptor subtypes.  相似文献   
603.
This study investigated the effect of fumarate (FUM) and rice bran (RB), alone and together, on in vitro rumen fermentation, methanogenesis and methanogens. In vitro incubation was performed with six media that were either unsupplemented (control) or supplemented with 10% RB, 5 mmol/L FUM, 10% RB + 5 mmol/L FUM, 10 mmol/L FUM, or 10% RB + 10 mmol/L FUM. Methane (CH4) production, dry matter digestibility, CH4 per digested dry matter, total short‐chain fatty acid (SCFA) production, proportion of SCFA, acetate : proprionate ratio, production of NH3‐N, and population density of rumen microbes were determined. Supplementation with 10% RB + 10 mmol/L FUM yielded a 36% decrease in CH4 production compared to the control. Supplementation of FUM, in the presence or absence of RB, provided increases in total SCFA production and propionate proportion up to 61% and 31%, respectively. Total bacteria, methanogens and protozoa populations were significantly (P < 0.05) decreased with the 10% RB + 10 mmol/L FUM supplementation. The effect of anti‐methanogenesis of FUM was enhanced by the addition of RB. Notably, the CH4 production attenuation was achieved by 10% RB + 10 mmol/L FUM without reduction of digestibility or of ruminal fermentation.  相似文献   
604.
The shut-off of host protein synthesis in virus-infected cells is one of the important mechanisms for viral replication. In this report, we showed that the HL strain of measles virus (MeV-HL) as well as other field isolates, which were isolated from human blood lymphocytes using B95a cells, induce the shut-off in B95a cells. Since the Edmonston strain of MeV failed to induce the shut-off in B95a cells, the ability to induce the shut-off was considered to be dependent on virus strains. Although, the modification of eukaryotic translation initiation factors (eIF) including eIF4G, eIF4E, and 4E-BP1 was reported for shut-off by various viruses, the involvement of these eIFs was not observed in MeV-HL-infected B95a cells. Instead, the accumulation of phosphorylated eIF2alpha was found to coincide to the decrease of host protein synthesis, suggesting the involvement of phosphorylation of eIF2alpha in inhibition of translation as one of the mechanisms of the shut-off.  相似文献   
605.
To make use of underutilized fish species and produce high-quality condiments substitutable for those of mammalian origin, fish sauces were produced on a small industrial scale from three fish species, the flyingfish Cypselurus agoo agoo, the small dolphinfish Coryphaena hippurus, and the deepsea smelt Glossanodon semifasciatus, using salt and koji mold. During 180 days of fermentation, the pH decreased to approximately 4.5 and total nitrogen and free amino acids increased to approximately 2 g/100 mL and 6000 mg/100 mL, respectively. Halophilic and extreme halophilic bacterial counts dramatically increased from 106 to 108 colony forming units/mL between days 14 and 30 and decreased the reafter. In the final products, the pH and salt concentration decreased to between soy sauce and a Vietnamese fish sauce, Nuoc mam. The total amino acid and organic acid contents were almost the same as those of Nuoc mam and soy sauce. Sensory evaluation found these products to have lower smell, saltiness, and bitterness, and higher sweetness and umami taste than Nuoc mam. During fermentation, the histamine content increased in one or two of three fermentation tanks for each fish species. As a result, the histamine content of the final products was higher than that in Nuoc mam.  相似文献   
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