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It was indicated from fluorescence spectra and fluorescence titration that a hydrophobic probe, 1-anilino-8-naphthalenesulfonate (ANS), binds to casein components (αs-, β- and κ-caseins). Fluorescence intensity and affinity of ANS-κ-casein complex were larger than that of ANS-αs- and ANS-β-casein complexes. Enhancements of fluorescence intensity of complexes of casein components were observed by the addition of KCI or CaCl2. Reason for the enhancement was postulated to be the increase of the quantum yield of the ANS fluorescence caused by the environmental change of ANS binding region of the casein components.

Marked increase of sedimentation coefficient of β-casein in the presence of KCl or CaCl2 at 10°C was caused by the addition of ANS. This may be responsible for the stimulation of the Ca-dependent precipitation of β-casein by the addition of ANS.

It was found that αs · κ-association was prevented by ANS and that hydrophobic interaction have an important role for αs · κ-association.  相似文献   
144.
The reversible interaction between dextran sulfate (D) and the low density lipoprotein of human serum (P) was investigated by sedimentation velocity. Analysis of the velocity patterns of dextran sulfate—lipoprotein mixtures revealed that the maximum number of binding sites on dextran sulfate molecule is approximately 6. It was also shown that the species of the complex formed is affected by the mixing ratio of the two constituents: at the molar ratio (P/D) 0.69, the complex exists in average as DP1.6 and at 0.98 as DP2.2. The linear increment of sedimentation coefficient of the complex due to the binding of one lipoprotein molecule was 7.8S. Finally, the mechanism of precipitation of the complexes was discussed.  相似文献   
145.
In order to obtain a basic information of plant cell suspension culture as a step toward the development of large scale culture, culture conditions of crown gall cells (auxin non-requiring cells) were investigated. Addition of yeast extract to culture medium was significantly effective for the growth and cell dispersion.

In experiments on the ability of the cultured cells to utilize sugars as the carbon source, it was observed that galactose, added to the culture medium, markedly inhibited the cell growth.

Pasteurization of the medium containing fructose as carbon source made it brownish by Maillard reaction and the medium apparently restrained the cell growth. However, the fructose medium sterilized by filtration was excellent for the cell growth as well as sucrose or glucose medium. In a jar fermentor, even the glucose medium became brownish by heat sterilization and the brown colored medium restrained the cell growth. Under optimum conditions, the doubling time was 1.1 day in exponential phase and 2.0 g of cell (dry weight) per 100 ml culture was obtained as the maximum yield.  相似文献   
146.
We have engineered a system that holds potential for use as a safety switch in genetically modified yeasts. Human apoptotic factor BAX (no homolog in yeast), under the control of the FBP1 (gluconeogenesis enzyme) promoter, was conditionally expressed to induce yeast cell apoptosis after glucose depletion. Such systems might prove useful for the safe use of genetically modified organisms.  相似文献   
147.
The transglucosidation reaction of brewer’s yeast α-glucosidase was examined under the co-existence of l-sorbose and phenyl-α-glucoside. As the transglucosidation products, three kinds of new disaccharide were chromatographically isolated. It was presumed that these disaccharides consisting of d-glucose and l-sorbose were 1-O-α-d-glucopyranosyl-l-sorbose ([α]D+89.0), 3-O-α-d-glucopyranosyl-l-sorbose ([α]D+69.1) and 4-O-α-d-glucopyranosyl-l-sorbose ([α]D+81.0). The principal product formed in the enzyme reaction was 1-O-α-d-glucopyranosyl-l-sorbose.  相似文献   
148.
Reports indicate that leaf onset (leaf flush) of deciduous trees in cool‐temperate ecosystems is occurring earlier in the spring in response to global warming. In this study, we created two types of phenology models, one driven only by warmth (spring warming [SW] model) and another driven by both warmth and winter chilling (parallel chill [PC] model), to predict such phenomena in the Japanese Islands at high spatial resolution (500 m). We calibrated these models using leaf onset dates derived from satellite data (Terra/MODIS) and in situ temperature data derived from a dense network of ground stations Automated Meteorological Data Acquisition System. We ran the model using future climate predictions created by the Japanese Meteorological Agency's MRI‐AGCM3.1S model. In comparison to the first decade of the 2000s, our results predict that the date of leaf onset in the 2030s will advance by an average of 12 days under the SW model and 7 days under the PC model throughout the study area. The date of onset in the 2090s will advance by 26 days under the SW model and by 15 days under the PC model. The greatest impact will occur on Hokkaido (the northernmost island) and in the central mountains.  相似文献   
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Despite efforts to elucidate its pathophysiology, ischemia–reperfusion injury lacks an effective preventative intervention. Because transient receptor potential cation channel subfamily M member 4 (TRPM4) is functionally expressed by many cell types in the cardiovascular system and is involved in the pathogenesis of various cardiovascular diseases, we decided to assess its suitability as a target of therapy. Thus, the aim of this study was to examine the possible cardioprotective effect of 9-phenanthrol, a specific inhibitor of TRPM4. Isolated Langendorff-perfused rat hearts were pretreated with Krebs–Henseleit (K–H) solution (control), 9-phenanthrol, or 5-hydroxydecanoate (5-HD, a blocker of the ATP-sensitive potassium channel) and then subjected to global ischemia followed by reperfusion with the K–H solution. To evaluate the extent of heart damage, lactate dehydrogenase (LDH) activity in the effluent solution was measured, and the size of infarcted area of the heart was measured by 2,3,5-triphenyltetrazolium chloride staining. In controls, cardiac contractility decreased, and LDH activity and the infarcted area size increased. In contrast, in hearts pretreated with 9-phenanthrol, contractile function recovered dramatically, and the infarcted area size significantly decreased. The cardioprotective effects of 9-phenanthrol was not completely blocked by 5-HD. These findings show that 9-phenanthrol exerts a cardioprotective effect against ischemia in the isolated rat heart and suggest that its mechanism of action is largely independent of ATP-sensitive potassium channels.  相似文献   
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