> From: rrg at aber.ac.uk (Roy Goodacre)
> Subject: Re: Are Viruses Living?
> In article <3nbbsj$i9r at d2.tufts.edu> welkin <wjohnson at opal.tufts.edu> writes:
> >ED at molbiol.uct.ac.za ("Ed Rybicki") wrote:
> >> > From: craigm at sanger.otago.ac.nz (Craig Marshall)
> >> > This seems to be a question with no answer. I would argue that there is
> >> > references for this claim). The property of replication is not
> >> > equivalent to life in the sense that a bacterium (or whatever) is
> >> > alive.
> >> This is snowballing nicely...B-)
> >> The above does not wash: the only difference between some bacteria and
> >> some viruses is that the former have membranes surrounding them and
> >> live? All that separates them and free-living bacteria is a few
> >> hundred million years of evolution, after all.
> >>And what about the endospores of species such
> >as Bacillus and Clostridium? They too are nothing
> >until placed in the right environment. If they are nlving
> >they do a remarkable job of propagating themselves
>> Yes ture but the point here is that they are viable and recoverable. And
> yes viable does = life ....
I make the point to my students that bacterial spores that have been
dessicated and kept for decades are qualitatively no different from
the tobacco mosaic virus inocula that Beijerinck put away, and which
were found (apprarently) to be infectious 90-odd years later.
What is the difference between a spore and a virion? If both can
withstand dessication to the point where no "life" can be sustained,
yet reconstitute "life" when given the correct milieu (=water and
air and nutrients for spores, cells for viruses), then surely both
have gone through a "non-living but viable" stage? Viable in the
sense of "capable of life"? Virions are just viral spores...! B-)
| Ed Rybicki, PhD | ed at molbiol.uct.ac.za |
| Dept Microbiology | University of Cape Town |
| Private Bag, Rondebosch | 7700, South Africa |
| fax: x27-21-650 4023 | phone: x27-21-650-3265 |
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