Degradation of cellular deoxyribonucleic acid after gamma irradiation of spheroplasted Escherichia coli CR thy- cells.
نویسندگان
چکیده
Gamma-ray-irradiated Escherichia coli CR thy(-) cells and spheroplasts, prelabeled with (14)C-thymine, were assayed for acid-insoluble activity as a function of incubation time after irradiation. Under similar irradiation and incubation conditions, degradation profiles of cells and spheroplasts were virtually identical. Similar results were found for cells and protoplasts irradiated in the presence of rifampin (20 mug/ml). These results suggest that postirradiation deoxyribonucleic acid degradation enzymes are probably not loosely localized in the periplasm, unlike endonuclease I.
منابع مشابه
استفاده از پرتوتابی گاما برای حذف آلودگی باکتریایی آغوز گاو
In order to colostrum pasteurization and creating of dose-response curve for Escherichia coli and Staphylococcus aurous, the colostrum of cow was gamma irradiated at doses of 0, 0.5, 1 and 2 KGy. Chemical composition, true protein, electrophoretic pattern of proteins, lactose content, peroxide level and pH of colostrums samples before and after of irradiation were determinate. The obtained...
متن کاملInfluence of thymine starvation on the integrity of deoxyribonucleic acid in Escherichia coli.
The influence of thymine starvation on the single-strand molecular weight of deoxyribonucleic acid (DNA) from Escherichia coli was determined by sedimentation through gradients of alkaline sucrose. Growth of cells for as long as 150 min in thymineless medium did not significantly reduce the molecular weight below the control value of 2.4 +/- 0.3 x 10(8) daltons. Incubation of cells in thyminele...
متن کاملrecA gene product is responsible for inhibition of deoxyribonucleic acid synthesis after ultraviolet irradiation.
Deoxyribonucleic acid synthesis after ultraviolet irradiation was studied in wild-type, uvrA, recB, recA recB, and recA Escherichia coli strains. Inhibition of deoxyribonucleic acid synthesis, which occurs almost immediately after exposing the cells to ultraviolet radiation, depends on the functional gene recA.
متن کاملLoss of photoreversibility of damage to deoxyribonucleic acid replication in ultraviolet-irradiated Escherichia coli B-r thy trp.
Loss of photoreversibility (LOP) of the ultraviolet (UV) damage which prevents reinitiation of deoxyribonucleic acid (DNA) replication occurred with incubation of Escherichia coli B/r thy trp cultures after UV doses of 240, 320, and 400 ergs/mm(2). LOP occurred at the time of reinitiation of DNA replication in the cultures (i.e., after postirradiation lag periods of 45 min or more). Neither the...
متن کاملRecombination-deficient mutant of Streptococcus faecalis.
An ultraviolet radiation-sensitive derivative of Streptococcus faecalis strain JH2-2 was isolated and found to be deficient in recombination, using a plasmid-plasmid recombination system. The strain was sensitive to chemical agents which interact with deoxyribonucleic acid and also underwent deoxyribonucleic acid degradation after ultraviolet irradiation. Thus, the mutant has properties similar...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of bacteriology
دوره 116 1 شماره
صفحات -
تاریخ انتشار 1973