X-Message-Number: 1052 From: (Number Ten Ox) Newsgroups: sci.bio,sci.med,sci.cryonics Subject: Re: Better Living through DNA Encryption Date: 23 Jul 1992 06:13:38 GMT Message-ID: <> References: <> <> <> In article <>, (kevin.q.brown) writes: [forwarded msg from Hugh Hixon] |> The radiation-resistant bug I know a little about is *micrococcus |> radiodurans*, and it was discovered during early attempts to radiation- |> sterilize foods. I believe it is an archebacterium. It withstands Hmmm. I studied this bug for my undergrad thesis, and last I remember (albeit five years ago) it was classified as a eubacterium. It's genus was changed a number of years ago from Micrococcus to Deinococcus, and it's one of a number of Deinococci with this amazing radiation resistance (ref: Brooks and Murray, 1981, Int. J. Syst. Bact., 31: 353). |> four million rads without special culturing, six million rads with special |> culturing, and has been cultured with fission products. It protects itself |> from radiation damage with large amounts of superoxide dismutase and catalase |> among other things. The original paper is at least 30 years old, and the |> author is Raj. I have the original citation as Anderson et al. (1956) Food Technology, v10, pp 575-577. When I studied this bug, it was far from clear that the antioxidant enzymes were responsible for the radiation resistance. My project was actually to purify the superoxide dismutase from D. radio- durans, so I was pretty familiar with the literature at the time. Have there been new reports in the last 5 years? I'd be interested to know, but I haven't been following the story very closely. My impression from my undergrad days was that the highly efficient DNA repair mechanisms of this bacterium were thought to be responsible for the unusual resistance. -- ____ Scott Keeney, DNA repair-queer ____ \ / \ / \/ Biochemistry and Molecular Biology \/ U.C. Berkeley Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=1052