The Effect of Internal Bacteria On the Human Body 227
meckdevil writes with this excerpt from the Miller-McCune magazine:
"In a series of recent findings, researchers describe bacteria that communicate in sophisticated ways, take concerted action, influence human physiology, alter human thinking, bioengineer the environment and control their own evolution. ... The abilities of bacteria are interesting to understand in their own right, and knowing how bacteria function in the biosphere may lead to new sources of energy or ways to degrade toxic chemicals, for example. But emerging evidence on the role of bacteria in human physiology brings the wonder and promise — and the hazards of misunderstanding them — up close and personal. ... Because in a very real sense, bacteria are us. Recent research has shown that gut microbes control or influence nutrient supply to the human host, the development of mature intestinal cells and blood vessels, the stimulation and maturation of the immune system, and blood levels of lipids such as cholesterol. They are, therefore, intimately involved in the bodily functions that tend to be out of kilter in modern society: metabolism, cardiovascular processes and defense against disease. Many researchers are coming to view such diseases as manifestations of imbalance in the ecology of the microbes inhabiting the human body. If further evidence bears this out, medicine is about to undergo a profound paradigm shift, and medical treatment could regularly involve kindness to microbes."
Anthropomorphic bacteria (Score:5, Informative)
I know it's a bit of nit-picking in an otherwise fascinating and informative article, but this bit about bacteria directing their own evolution is quite unfounded and - I suspect - added to sensationalize a teeny bit.
Bacteria do engage in horizontal gene transfer, and so can shape their own genomes beyond relying on random mutation (which is perfectly reasonable and expected, given that us dumb eukaryotes have even figured out how to do that part pretty well). However, to suggest that the bacteria are making "intentional changes to their heritable scaffolding" with some kind of intelligence is anthropomorphizing a little overmuch, especially with this part: "To suggest that organisms as primitive as bacteria are capable of controlling their own evolution is obviously silly. Isn’t it?" Yes, bacteria can share genetic material and yes, some bits of material (plasmids!) seem developed almost explicitly to do this, but evidence of "intentions" or "control" behind their evolutionary direction is lacking. Bacteria share genes; the ones who pick up successful (eg, antibiotic resistance) genes survive and proliferate. Natural selection favors mobility of these situationally beneficial genes (and, one must note, only when they are beneficial; they otherwise drop rather rapidly out of the population) and the bacteria who harbor them, just like every other living thing on the planet.
Final note: no serious tree of life puts humans at the "apex." To do so is to misunderstand evolutionary theory: we are just as "evolved" as every other extant life form.
Sincerely,
A Pedantic Biologist
Re:Bacteria - real life nanobots (Score:2, Informative)
nevermind even knowing which, why, how.
Imagine the magic be thin pill: a daily capsule of select bacteria, little to no side effects.
Or, as discussed in the article, a fecal transplant...
Re:Different bacteria in different parts of the wo (Score:5, Informative)
Re:10x (Score:1, Informative)
There are cases where antibiotics have killed off friendly bacteria and unfriendly types become a problem.
In the case of Pseudomembranous colitis [wikipedia.org]
one effective treatment amounts to a poop transplant [wikipedia.org]. No joke!
Re:This means giving up (Score:4, Informative)
the eradication of all even potentially pathogenic bacteria living in the human host
You would die. You would completely keel over and be an ex-parrot.
You rely on bacteria just to get through the day, and *all* are potentially pathogenic. There is e. coli that lives in your gut happily digesting food and helping give you vitamin B, and then there is e. coli that can kill you dead via food poisoning. It only takes a few gene swaps to make one the other, and bacteria do this all the time on their own.
Ask myself? I did. I answered "he's a nut."
--
BMO
Re:10x (Score:5, Informative)
Hate to quote Wikipedia, but: "Citation needed."
If you can quote Wikipedia, I can cite it.
The average human body, consisting of about 1013 (10,000,000,000,000 or about ten trillion) cells, has about ten times that number of microorganisms in the gut.
http://en.wikipedia.org/wiki/Human_flora#Gut_flora [wikipedia.org]
Of course, bacteria are much smaller than animal cells. Its a bit like saying cars contain more dirt particles than functioning components.
Re:Different bacteria in different parts of the wo (Score:2, Informative)
Perhaps you could make your post more informative, by showing us both the mechanism for converting sugars(and starches) to body fat, and the mechanism for converting dietary fat into bady fat - And demonstrate that the second is "easier" than the first.
For extra credit you can shoot for insightful and show us that the body stores fat even when glucose(blood sugar) levels are low.
Re:The reason everyone is lactose intolerant... (Score:3, Informative)
Anyone who is lactose intolerant simply does not have the mutation allowing the production of lactase beyond the juvenile stage of developement. It's a mutation, you either have it, or you don't. No bacteria involved.
Re:This means giving up (Score:3, Informative)
Prune,
Humans are living organisms, not well-understood machines. We are also ecosystems. The relationship between us and our microflora is part of the deal. You can't just eliminate it, nor is there any need or benefit in doing so if you could.
The notion that trying to understand this vital relationship and working with it is somehow "cowardly" or an abdication of progress is absurd. It is an important step forward for medicine and biology, a recognition of another level of complexity.
This post and your previous one make you out to be some kind of control freak. Do you want to be a sterilized brain in a vat? Or maybe you'd rather download yourself into a robot body.
Or maybe you're just trolling for reactions.
Re:The reason everyone is lactose intolerant... (Score:3, Informative)
No bacteria involved.
That's not strictly true, in that even if you're not producing lactase a steady, lowish level consumption of milk products can lead to enough lactose-digesting bacteria in your guts to allow some dairy consumption without the usual side effects. But the GP is totally wrong about UHT milk, as pointed out by others above.
Re:Different bacteria in different parts of the wo (Score:3, Informative)
I get the impression that you use word "sugar" to mean carbohydrates in general, and not just what is usually meant by sugars: sweet mono- and disaccharides. I don't see a lot of those behind that link, it ceratinly is not "primarily sugar diet".
I mean, earlier you talked about food that takes long to digest. Long-chained carbohydrates are just that, their rate of digestion is just about right for the common interval between meals.