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A genetically modified bacterium that outcompetes bacteria causing tooth decay

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Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#21

Post by margalabargala »

david_l_lin wrote: post #20

This story has been around for far too long and evidence is unbelievably weak, and the claims border on fraudulent. 1. The claim that this strain outcompetes the same S mutans from occupying the same niche cannot be true unless this strain is also capable of creating and tolerating environments with low pH. By definition if it creates acid to the same degree it will also cause cavities. 2. Single applications are ins…

Your first point seems wrong.

> cannot be true unless this strain is also capable of creating and tolerating environments with low pH

Whether it can tolerate low pH environments is not particularly related to whether it creates low pH environments. If it's agnostic to pH levels around that range, then it can inhabit that niche whether or not there is acid being secreted.

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#22

Post by jussij »

elcritch wrote: post #15
jussij wrote: post #12

Earlier quoted context omitted.

Do you have any examples of how the FDA is starting to put corporate interest ahead of public interest?

I’d say corporate and good-old-boy senior researcher clubs: https://www.nbcnews.com/news/amp/rcna63662

It's very difficult for any major institution to not have problems similar to this, as there will always be individuals in positions of power who take it upon themselves to make decisions that can be construed as corrupt. However, the fact this issue was revealed to the public, reported widely and also found to be a highly dubious shows the institute is working fine. They appear to have systems and processes in place to help stop these kinds of dubious decisions, and because of the blowback from this rather poor decision, I'm certain the people at the FDA working the next round of approvals will make sure they hold up to scrutiny, which will be stronger than ever.

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#23

Post by pkaye »

Is there a way to determine if FDA actually set this requirement for the study? Is it on public record? Or do we just have to rely on what they claim.

Also why not try getting it approved elsewhere first like in the EU if FDA is making it harder to approve?

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#24

Post by margalabargala »

gamblor956 wrote: post #16

This seems like a scam... The author claims that the FDA set impossible standards for getting this approved when it was originally discovered and that those same standards prevent them from seeking FDA approval now....but further down acknowledges that probiotics like this product are actually subject to much more lenient standards.

I think you misunderstood the author.

The treatment was proposed to the FDA decades ago as a drug. The drug approval process yielded the impossible ask. Those same standards prevent them from seeking FDA approval now as a drug.

That this could be approved as a probiotic is a recent idea. The impossible standards are not the probiotic lenient standards.

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#25

Post by david_l_lin »

margalabargala wrote: post #21
david_l_lin wrote: post #20

This story has been around for far too long and evidence is unbelievably weak, and the claims border on fraudulent. 1. The claim that this strain outcompetes the same S mutans from occupying the same niche cannot be true unless this strain is also capable of creating and tolerating environments with low pH. By definition if it creates acid to the same degree it will also cause cavities. 2. Single applications are ins…

Your first point seems wrong. > cannot be true unless this strain is also capable of creating and tolerating environments with low pH Whether it can tolerate low pH environments is not particularly related to whether it creates low pH environments. If it's agnostic to pH levels around that range, then it can inhabit that niche whether or not there is acid being secreted.

I should clarify: there’s some more details to why S mutans actually requires low pH. The correct term wouldn’t be “tolerate low pH” but rather “requires low pH” for its stable colonization.

S mutans creates incipient lesions by making acid, incipient lesions are micro environments where the low pH that causes enamel decay is determined by the biofilm on its surface. S mutans cannot thrive in environments with neutral or high pH. the existing community (including other Streptococcus species) create local alkaline environment via multiple metabolic pathways, including the most well studied and prevalent arginine deiminase system. A “normal” healthy community antagonizes S mutans by maintaining a normal pH in saliva and the tooth surface, preventing stable colonization by S mutans.

Without acid production, S mutans cannot stably colonize. and is readily outcompeted by the existing community. Any novel strains of S mutans to “compete for the same niche” will suffer the same weakness unless they create acid. but if this “probiotic” also creates acid, then by definition it also causes cavities.

edit: adding citation https://www.futuremedicine.com/doi/10.2217/fmb-2018-0043

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#26

Post by clumsysmurf »

I use a similar product, LEF Florassist Oral

https://www.lifeextension.com/vitamins-supplements/item02120...

That has BLIS M18™ and Immuno-LP20®

BLIS M18: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9012604/

I have not noticed any difference.

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#27

Post by space_fountain »

david_l_lin wrote: post #20

This story has been around for far too long and evidence is unbelievably weak, and the claims border on fraudulent. 1. The claim that this strain outcompetes the same S mutans from occupying the same niche cannot be true unless this strain is also capable of creating and tolerating environments with low pH. By definition if it creates acid to the same degree it will also cause cavities. 2. Single applications are ins…

A part of the story that has always made the claim more plausible to me is the claim that apes tend not to get cavities at the same rate we do. Since they have teeth that are as susceptible to acid as ours the story goes their diet tends to lead to other populations of bacteria in their mouthes out competing the cavity causing ones. Then people will go on to say that this ecosystem of mouth bacteria have co-evolved. The reason we have so much trouble is that we've changed our diets drastically relatively recently aka a few hundred thousand years. It sounds like you would argue that some part of that story is wrong. Maybe the bit where eventually a less damaging microbiome would evolve?

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#28

Post by elcritch »

jussij wrote: post #22
elcritch wrote: post #15

Earlier quoted context omitted.

I’d say corporate and good-old-boy senior researcher clubs: https://www.nbcnews.com/news/amp/rcna63662

It's very difficult for any major institution to not have problems similar to this, as there will always be individuals in positions of power who take it upon themselves to make decisions that can be construed as corrupt. However, the fact this issue was revealed to the public, reported widely and also found to be a highly dubious shows the institute is working fine. They appear to have systems and processes in place…

Of course major institutions will always face these sorta problems.

However your comment seems to assume the FDA self-corrected. They faced a lot of external criticism and eventually partially capitulated. Even then they just restricted its listed audience.

> They appear to have systems and processes in place to help stop these kinds of dubious decisions

Except that it was external pressure that forced changes, not internal processes. The congressional report found that the FDA violated their own processes. Thankfully we still have a fairly transparent government and the incident was made public.

Though congress seems to have just given them a slap in the wrist. No officials were fired AFAICT, why wouldn't other FDA officials do the same in the future? Based on the parent article it might still be happening.

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#29

Post by mplewis »

space_fountain wrote: post #27
david_l_lin wrote: post #20

This story has been around for far too long and evidence is unbelievably weak, and the claims border on fraudulent. 1. The claim that this strain outcompetes the same S mutans from occupying the same niche cannot be true unless this strain is also capable of creating and tolerating environments with low pH. By definition if it creates acid to the same degree it will also cause cavities. 2. Single applications are ins…

A part of the story that has always made the claim more plausible to me is the claim that apes tend not to get cavities at the same rate we do. Since they have teeth that are as susceptible to acid as ours the story goes their diet tends to lead to other populations of bacteria in their mouthes out competing the cavity causing ones. Then people will go on to say that this ecosystem of mouth bacteria have co-evolved.…

The idea that primates get cavities less frequently than modern humans is a bit outdated and not terribly supported by recent studies. The main difference is in the location of the cavities, not frequency – apes tend to get cavities in their front teeth, humans tend to get cavities in the molars.

Re: A genetically modified bacterium that outcompetes bacteria causing tooth decay

#30

Post by space_fountain »

david_l_lin wrote: post #25
margalabargala wrote: post #21

Earlier quoted context omitted.

Your first point seems wrong. > cannot be true unless this strain is also capable of creating and tolerating environments with low pH Whether it can tolerate low pH environments is not particularly related to whether it creates low pH environments. If it's agnostic to pH levels around that range, then it can inhabit that niche whether or not there is acid being secreted.

I should clarify: there’s some more details to why S mutans actually requires low pH. The correct term wouldn’t be “tolerate low pH” but rather “requires low pH” for its stable colonization. S mutans creates incipient lesions by making acid, incipient lesions are micro environments where the low pH that causes enamel decay is determined by the biofilm on its surface. S mutans cannot thrive in environments with neutra…

So to be specific what you're skeptical of here is that S. mutans can outcompete other bacteria without its ability to generate acid If this engineered version can stay in the mouth it should be able to live in the exact same lesions the non mutated version can right? It should still have all the adaptations to live in a low pH environment. I guess this is an extraordinary claim so it's right to be more cautious than the internet usually is, but that also seems to be an easy thing to test for. You can swab someone's mouth who's taken this and see if they still have the mutated bacteria or if it's been out competed
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