Changes

:::::The whole point of the discussion above was to illustrate that there are methods to isolate cells with a particular genotype from a mixed population.  Suppose we used the replica plating method (maybe not the best choice, but it's standard procedure).  Care to explain where the Cit+ contaminants could possibly come from?  And the naivete inherent in objecting that "nothing in the paper" rules it out is simply astounding.  Standard laboratory procedures, like isolating specific clones, typically don't show up in papers.  For example, if I to write a paper on my research, it would not include a detailed discussion of the construction of my expression plasmid.  I might mention that I cloned my gene into a particular vector, but there wouldn't a discussion of how I did my PCR, restriction digests, or transformations.  Things like that are simply extraneous details that are taken for granted by experienced researchers.  There is simply no reason for Lenski et al. to include a discussion of their method for isolating specific clones.  This is why this whole exercise of Conservapedia criticizing Lenski's paper is folly, because most Conservapedia users simply don't know standard laboratory techniques. It's kind of important to know what scientists today are able to do on a routine basis before wading in to claim that they couldn't have done what they claim.[[User:Gerlach|Gerlach]] 09:05, 15 July 2008 (EDT)

:::::The whole point of the discussion above was to illustrate that there are methods to isolate cells with a particular genotype from a mixed population.  Suppose we used the replica plating method (maybe not the best choice, but it's standard procedure).  Care to explain where the Cit+ contaminants could possibly come from?  And the naivete inherent in objecting that "nothing in the paper" rules it out is simply astounding.  Standard laboratory procedures, like isolating specific clones, typically don't show up in papers.  For example, if I to write a paper on my research, it would not include a detailed discussion of the construction of my expression plasmid.  I might mention that I cloned my gene into a particular vector, but there wouldn't a discussion of how I did my PCR, restriction digests, or transformations.  Things like that are simply extraneous details that are taken for granted by experienced researchers.  There is simply no reason for Lenski et al. to include a discussion of their method for isolating specific clones.  This is why this whole exercise of Conservapedia criticizing Lenski's paper is folly, because most Conservapedia users simply don't know standard laboratory techniques. It's kind of important to know what scientists today are able to do on a routine basis before wading in to claim that they couldn't have done what they claim.[[User:Gerlach|Gerlach]] 09:05, 15 July 2008 (EDT)

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:::::Actually the methods cited in the paper would separate the Cit+ lines from the Cit-. They took single colonies (founded by single cells), and tested them on selective agar (minimal citrate media - MC agar) and an indicator medium, Christensen's citrate agar (Product information from Sigma here: http://www.sigmaaldrich.com/sigma/datasheet/c7595dat.pdf). As Gerlach notes from the Blount paper, Christensen's citrate agar is very sensitive to citrate utilization. E.coli strains do not produce a color change but other citrate-using enterics like ''S. typhimurium'' and Cit+ ''E. coli'' mutants appear pink/red on the plates.

:::::Actually the methods cited in the paper would separate the Cit+ lines from the Cit-. They took single colonies (founded by single cells), and tested them on selective agar (minimal citrate media - MC agar) and an indicator medium, Christensen's citrate agar (Product information from Sigma here: http://www.sigmaaldrich.com/sigma/datasheet/c7595dat.pdf). As Gerlach notes from the Blount paper, Christensen's citrate agar is very sensitive to citrate utilization. E.coli strains do not produce a color change but other citrate-using enterics like ''S. typhimurium'' and Cit+ ''E. coli'' mutants appear pink/red on the plates.