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41.
Pamela M. Reilly Dr. Palmer Rogers 《Journal of industrial microbiology & biotechnology》1987,1(5):329-334
Summary Conditions that allow regeneration of cells fromClostridium acetobutylicum strain B643 protoplasts were studied. Protoplast formation and stabilization in minimal media with 50 mM CaCl2, 50 mM MgCl2 and 0.3 M sucrose were crucial to subsequent regeneration on soft yeast extract agar containing 25 mM CaCl2 and 25 mM MgCl2. A regeneration frequency of 8–25% was consistently obtained. 相似文献
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Pamela J. Letts Les Pinteric Harry Schachter 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,372(2):304-320
Golgi fractions prepared from rat testis have been shown to be enriched in the following glycoprotein glycosyltransferases: N-acetylglucosaminyltransferase, 47-fold, galactosyltransferase, 33-fold, and N-acetylglucosaminide fucosyltransferase, 15-fold. Appreciably lower transferase levels were obtained in other subcellular fractions. In the mouse, Golgi fractions were prepared from testis homogenates, testis cell suspensions and partially purified testis germinal cells; these fractions were also enriched in the above glycoprotein glycosyltransferases. Electron microscopic analysis indicated that a major portion of the total transferase activity was located in the Golgi apparatus of both rat and mouse testis although these experiments could not rule out the possible presence of some transferase activity in other organelles. 相似文献
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Initiation of Germination and Inactivation of Bacillus pumilus Spores by Hydrostatic Pressure 总被引:5,自引:3,他引:2 下载免费PDF全文
The effect of hydrostatic pressures as high as 1,700 atm at 25 C on the heat and radiation resistance of Bacillus pumilus spores was studied. Phosphate-buffered spores were more sensitive to compression than spores suspended in distilled water. Measurements of the turbidity of suspensions, the viability, refractility, stainability, dry weight, and respiratory activity of spores, and calcium and dipicolinic acid release were made for different pressures and times. Initiation of germination occurred at pressures exceeding 500 atm and was the prerequisite for inactivation by compression. The rate of initiation increased with increasing pressure at constant temperature. This result is interpreted as a net decrease in the volume of the system during initiation as a result of increased solvation of the spore components. 相似文献
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A marked increase in the isolation of Group B streptococci from patients in the University Hospital, Saskatoon, has been noted over the past four years, and no change in technical methods has been found to explain this increase. Group B streptococci have been isolated from 242 patients, in 53 of whom the streptococcus was considered the cause of the infection. Infections occurred predominantly in the urinary tract, female genital tract and upper respiratory tract. There was a low incidence of infections in newborn infants, and only four infections were in patients under 1 year old. Infections were more frequent in women than men and in patients over 40 years of age. No particular affinity of Group B streptococci for diabetics was demonstrated. 相似文献
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