In article <5bfqeg$555 at mserv1.dl.ac.uk>, "g.clark" <g.clark at lshtm.ac.uk> wrote:
>>>Perhaps the 'rules' are different for bacteria but I do not think species
>>>should be described on the basis of rDNA alone. In eukaryotes there are
>>>examples of bona fide biological species (i.e. unable to interbreed) of
>>>the ciliate Tetrahymena that have identical small subunit ribosomal RNA
>>>sequences. Therefore identical sequence does not mean same species.
>>>>>>IMHO you need more than just sequence variation to warrant the
>>>recognition of a new species. But perhaps bacteriologists feel differently.
>>>
Graham,
Thanks for your comments....I am indeed interested in BACTERIA.
My impression of the situation with bacteria is that the 16S rRNA
sequence is the "GOLD STANDARD" for designating (or identifying) a
bacterium at the species level. I'm just not sure how much of the
16S rRNA sequence one needs to be able to accomplish this task (as I
queried in my original posting).
-David
