Comment by Grimblewald

I would say the author has some more substantial problems raised in the article. From the article, it seems the people pushing lumina as that we accept something which is unlikely to solve the issue (mutans is not the sole or even the probable cause of caries, just one of many) and this strain of bacteria is likely to pickup the pathogenic genes over time for higher lactic acid production, and it is no less likely than its pathogenic counterpart to produce biofilms. So now you have a bacterium that is more stubborn, and is at best going to out-compete a narrow band of microbes, some of which might be pathogenic, until it itself becomes pathogenic at some point. Now you have the same problems, with extra moving parts introduced where things can go wrong. What happens if your body becomes sensitive to the toxin this strain produces and you end up with horrific gingivitis that cannot be readily cured?

That isn't a great sales pitch.