نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه زیست شناسی، دانشکده علوم پایه، دانشگاه الزّهرا(س)، تهران- ایران
2 حوزه معاونت دانشجویی، وزارت علوم، تحقیقات و فناوری، صندوق پستی: 1513-14665، تهران- ایران
کلیدواژهها
عنوان مقاله English
نویسندگان English
In this work, the capacity of an extreme halophilic archaebacterium, isolated from Uromia lake, Haloferax radiotolerans to withstand the lethal effects of ultraviolet light (UV),and 60Co r-rays has heen studied. The resistibility of this organism against the DNA-damaging agents was evaluated by calculating of the survival fractions at different dose rates of UV and 60Co r-rays radiations and compared with those of Escherichia coli B/r (a radioresistant strain of E. coli). D37 values for Haloferax radiotolerans and E. coli B/r were 231, and 9 J/m2, respectively, by exposure to the UV light. They were 645, and 99 Gy, respectively, by exposure to 60Co r-rays. Against these agents, Haloferax radiotolerans shows much more resistance compare to that of E. coli B/r. This is catogorized as the first report of resistibility in the member of Archaea.
کلیدواژهها English
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