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641.
Miso is a fermented food widely consumed in the Orient and is prepared from mold rice, soybeans and salt. About 13 million bushels of soybeans are made into miso each year, the annualproduction amounting to 974,000 metric tons. 相似文献
642.
Heat-induced blebbing and vesiculation of the outer membrane of Escherichia coli. 总被引:7,自引:0,他引:7
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N Katsui T Tsuchido R Hiramatsu S Fujikawa M Takano I Shibasaki 《Journal of bacteriology》1982,151(3):1523-1531
Thermal damage to the outer membrane of Escherichia coli W3110 was studied. When E. coli cells were heated at 55 degrees C in 50 mM Tris-hydrochloride buffer at pH 8.0, surface blebs were formed on the cell envelope, mainly at the septa of dividing cells. Membrane lipids were released from the cells during the heating period, and part of the released lipids formed vesicle-like structures from the membrane. This vesicle fraction had a lipopolysaccharide to phospholipid ratio similar to that of the outer membrane of intact cells, whereas it had a lower content of protein than the isolated outer membrane. After heating bacterial cells at 55 degrees C for 30 min, the resulting leakage from the cells of a periplasmic enzyme, alkaline phosphatase, amounted to 52% of the total activity, whereas no release of a cytoplasmic enzyme, glucose-6-phosphate dehydrogenase, was detected. The results obtained suggest that surface blebs formed by heat treatment almost completely consist of the outer membrane and that the blebs may be gradually released from the cell surface into the heating menstruum to partially form vesicles. 相似文献
643.
Koichi Shibasaki Masatoshi Kimura Ryuichi Ikarashi Akira Yamaguchi Takuya Watanabe 《Metabolomics : Official journal of the Metabolomic Society》2012,8(3):484-491
To date, few studies have examined uric acid in saliva or dental calculus. The purpose of this study is to examine the uric acid concentration in saliva and serum. Saliva and blood samples were collected from 244 participants. We divided them into four groups: untreated or treated group in normal or abnormal serum uric acid concentration groups. Within the untreated group, Pearson??s correlation coefficient was used to examine the correlation between salivary and serum uric acid concentrations. We compared uric acid concentrations between saliva and serum, or between untreated and treated groups using the paired or unpaired student??s t-test. In the untreated group, uric acid concentrations in saliva and serum were significantly and positively correlated (r?=?0.503, P?<?0.01). Within the untreated group, those with abnormal serum uric acid concentrations had significantly higher uric acid concentrations in serum and saliva compared to those with normal serum uric acid concentrations (P?<?0.01). Within the untreated group, uric acid concentrations in serum were significantly higher than that in saliva (P?<?0.01). Uric acid concentrations in saliva of the treated group were significantly higher than that of the untreated group (P?<?0.01). Within the treated group, uric acid concentrations in saliva were significantly higher than that of serum, particularly in users of benzbromarone (P?<?0.01). Uric acid concentrations in saliva were lower than that in serum among non-users of benzbromarone. In contrast, uric acid concentrations in saliva of patients taking benzbromarone were higher than that in serum. We surmise that URAT1 may influence uric acid excretion in the salivary gland. 相似文献
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The formaldehyde dehydrogenase (EC 1.2.1.1) from the yeast Pichia pastoris IFP 206 was purified to homogeneity. The enzyme had a molecular weight of 84,000 daltons and was composed of two identical subunits of a molecular weight of 39,000 daltons. The N-terminal end of the subunits is blocked. The protein showed 6,3 free -SH groups per mole and 12,5 in the presence of NAD+. Enzyme stability was increased by addition of glycerol during the purification.The enzyme activity is NAD+ and glutathione dependent. The reaction product is S formylglutathione. The presence of an S-formylglutathione hydrolase (EC 3.1.2.12) in the cell free extract was detected. The formaldehyde dehydrogenase showed an optimum pH of 7.9 and an optimum temperature of 47°C. The activation energy was 3.2 kcal/mol. The Michaelis constants for NAD+ and S-hydroxymethyl glutathione were respectively 0.24 mM and 0.26 mM. 相似文献
646.
Light-driven sodium-pumping rhodopsins are able to actively transport sodium ions. Structure/function studies of Krokinobacter eikastus rhodopsin 2 (KR2) identified N61 and G263 at the cytoplasmic surface constituting the “Ion-selectivity filter” for sodium ions, while retinal Schiff base acts as the light “Switch and Gate” for transport of sodium ions. Q123 is located between the two regions, and plays an important role for the pump function, which was implicated by functional, spectroscopic, X-ray crystallographic and computational studies. According to the atomic structure of KR2, Q123 is involved in the hydrogen-bonding network at the cytoplasmic region, together with S64, protein-bound waters, and peptide carbonyl of K255 bound to the chromophore. To gain the detailed structural information around Q123, here we compared light-induced difference Fourier-transform infrared (FTIR) spectra at 77?K between the wild-type (WT) and mutant proteins of KR2, such as Q123A, Q123V, and S64A. The obtained spectra were very similar between WT and these mutants, whereas the observed mutation effects enabled us to identify vibrations of the hydrogen-bonding network at the Q123 and S64 region. This is unique for KR2, not for the corresponding mutations in a light-driven proton-pump bacteriorhodopsin (BR). Hydrogen-bonding alteration is absent for the mutants of KR2, suggesting that proper inter-helical connectivity of helices B, C, and G is important for protein structural changes for sodium-pump function, which is controlled by the region around Q123. 相似文献
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Effects of adrenergic blockers on corticotropin-releasing factor-induced behavioral changes in rats 总被引:1,自引:0,他引:1
The effects of adrenoreceptor blocking agents on corticotropin-releasing factor (CRF)-induced behavioral changes in rats were examined. The i.c.v. injection of 1 micrograms ovine CRF significantly increased the grooming frequency, number of occurrences of rearing and total distance moved. I.c.v. administered phentolamine at a dose of 10 nmol completely suppressed the increase in rearing and total distance moved induced by CRF without affecting the grooming frequency, whereas 100 nmol phentolamine significantly decreased the grooming frequency as well as the rearing and total distance moved. In contrast, propranolol reduced the increase in rearing induced by CRF only at a dose which induced ataxia in rats. The increases in rearing and total distance moved induced by CRF were reduced by 10 nmol of yohimbine and 100 nmol of prazosin. S.c. injection of caffeine (10 mg/kg) produced a significant increase in grooming frequency, rearing, and total movement. Administration of 10 nmol phentolamine and yohimbine did not affect these behavioral changes induced by caffeine, while 100 nmol prazosin suppressed them. Therefore, prazosin depressed the behavior of rats non-specifically. These results suggest that CRF-induced behavioral hyperactivity is mediated at least in part by alpha-noradrenergic, mainly alpha 2-noradrenergic, systems in the brain. 相似文献