I recently released a podcast episode with Aaron Silverbook, a person within the LW-o-sphere, about his new start-up that produces a bacterium that might cure cavities, and also how cavities work and what's up with the bacteria we all have coating our teeth.
Here are links to Lumina Probiotic (the brand name of this new type of bacterium) and Lantern Bioworks (the company making the bacterium).
There are plenty of biology questions where I feel like Aaron Silverbook should study them more to be able to give answers.
One of them was why about mutacin 1140 and why it's no problem of the new bacterium. I would be pretty certain that given that the new bacteria was grown in a culture after getting the gene to produce mutacin 1140 it likely evolved changes to be able to partly immunize itself against mutacin.
While those mutations were not explicitly inserted, they likely evolved under evolutionary pressure.
i am still convinced, that this will cause unknown implications after oral sex. as lactic acid is the main factor balancing the female intime floral ph.So introducing a bacteria that prevents this might be problematic.
Streptococcus mutans is not part of the vaginal microbiome. Lactobacillus seems responsible for lactic acid production in the vagina. Lactobacillus is also present in the mouth but it's unlikely that this intervention will do anything to reduce the amount of Lactobacillus in the mouth let alone in the vaginal microbiome.