Gut flora helps the body produce vitamin C
We live in a time and age where decades old assumptions about the human body are being overturned on a surprisingly regular basis. For instance, bodily cells were recently found to communicate inheritable information to sex cells (e.g. sperm) capable of being passed down to the next generation, effectively challenging the exclusivity of Darwinian forms of inheritance in favor of including the long denied Larmarckian view. Last year, edible plant material was found to 'talk' to the cells in our body via nanoparticles known as exosomes that regulate the expression of our DNA, as well as other important physiological pathways. This month, we reported on research showing that mammalian cells are capable of extracting energy directly through the sun with the help of the 'plant blood' molecule chlorophyll. Even more amazing may be Gerald Pollack's notion that water's hypothesized fourth phase acts like a battery within the body, providing a continuous source of sunlight-driven energy that requires no intermediary to convert directly to biochemical energy through the charge separation it affects in water.
These are only small sampling of new, scientifically confirmed discoveries that fly in the face of conventional scientific wisdom, opening up possibilities in nutrition and medicine that may contribute to radically safer and more effective therapeutic interventions in the near future.
'Germs' makes us supra-human?
Recently, I had a rather stimulating email exchange with my colleague Stephanie Seneff, PhD, who pointed out a study she had found wherein it was discovered that the human microbiome is capable of producing vitamin C. This is a remarkable possibility, as the human body is not believed capable of producing this essential vitamin, long since our hominid ancestors lost the genetic ability to do so about 60 million years ago. The microbiome, however, is part of the new definition of the human body as a meta-organism, consisting of trillions of other microbial organisms and viruses without which we would never have survived. Also known as the hologenome theory of evolution, the idea is that the object of natural selection is not the individual organism, but the holobiont, i.e. the individual organism plus its associated microbial communities which include a mind numbingly complex web of bacteria, viruses, protozoa, helminths and fungi. In fact, if one looks at the genetic contribution of the human genome versus the total set of genes represented by the other organisms that make up the holobiont our genes only account for about 1%.
Not only is this a real ego challenge to anthropocentric and germophobic thinkers, but it reveals just how many capabilities we may borrow from these tiny co-inhabitants. For instance, recent research shows that our body draws from over 90 different bacterial strains in our gut to digest the gluten proteins in wheat that our own genome does not readily enable us to break down with any efficiency. Another cool example of how 'germs' help us to compensate for our genetic defects is the discovery that a certain Lactobacillus strain of food importance is capable of producing the active methylated form of folate -- 5-methylenetetrahydrofolate -- that those with MTHFR mutations are notoriously poor at producing in optimal quantities. We can assume, therefore, that single nucleotide polymorphisms (SNPs) are not the final story on nutritional deficiencies or aberrations, but that our microbial friends may fill in gaps or voids that our genes are not capable satisfying.
In this sense, the microbial portion of the holobiont significantly extends our genetic and/or epigenetic capabilities, making it possible to survive the ever-shifting ecological, environmental, nutritional niches that we have traversed in our seemingly infinitely long march (biological time stretching back millions of years) to our present-day incarnation. Whereas the primary nucleotide sequences in our DNA may require tens, hundreds and even millions of years to be significantly and/or functionally altered, microbial DNA contributions may shift in years, months, weeks, minutes and perhaps even in real-time in a matter of seconds. Can you see why Nature has compelled us into collaborating and even incorporating 'germs' into our body (note: the mitochondria in our body, according to the endosymbiotic view, were once proteobacteria outside of us!).
How we produce vitamin C
And so, it was within the context of this new understanding of the human body and it's physiological capabilities that Seneff and I explored the possibility of vitamin C producing bacteria in our gut.
The paper where this idea first emerged was published in titled, "Bacteria as vitamin suppliers to their host: a gut microbiota perspective." The remarkable paper focused on the role of food-related lactic acid bacteria (as found in cultured foods such as yogurt) as well as human gut commensal such as bifidobacteria and their ability to produce the vitamins we are not able to produce ourselves. The highlight, of course, was the discovery that bacterial isolates from human gut samples were capable of producing a wide range of vitamins, including vitamin C (ascorbate):
Unfortunately, the paper did not discuss the methodological details as to how exactly they uncovered this fact. And so, in an effort to validate this study I did an extensive database search until I discovered a concrete example of a bacterial strain known to inhabit the human body that is capable of producing ascorbate: Corynebacterium glucuronolyticum (ATCC 51867), which contains an L-ascorbate biosynthesis pathway depicted below.Notably, vitamin metabolism pathways were shown to be highly represented in all enterotypes, while two enterotypes were particularly enriched in genes that specify the biosynthetic enzymes for biotin, riboflavin, pantothenate, ascorbate, thiamine and folate production. These phylogenetic and functional differences among enterotypes thus reflect different combinations of microbial trophic chains with a probable impact on synergistic interrelations with the human host." [emphasis added]
Interestingly, most Corynebacterium species are considered benign, but C. glucouronolyticum has been been linked to human urogential infections, and C. diphtheria is associated with opportunistic diphtheria infections. Emerson once said that a weed is an herb whose virtues have yet to be discovered. So too may be the case with 'germs.' A nuisance, perhaps, may grow into greater numbers when the body is suffering from a deficiency of one of its primarily biosynthetic pathways and associated biomolecule, be it a vitamin, anti-tumor agent, or antibiotic. It is possible that C. glucuronolyticum grows into 'infectitious' proportions when the body is starved in vitamin C, and that when the body is replete with vitamin C the normally benign strain does not contribute to urogenital infection.
Of course this discovery does not prove that the gut flora are capable of producing physiological relevant quantities of vitamin C via this strain alone. But it does prove that it is for the human body to produce vitamin C -- further exemplifying how little we know about the human body, and again, how vitally important the 'germs' may be in helping us to compensate for our genetic impairments. I've always struggled with the idea that our ancestors were somehow able to survive 60 million years completely dependent on dietary sources of vitamin C, when an extreme deficiency (an inevitability given the famine-fast fluctuations of hunter-gatherer modes of subsistence) could result in severe debilitation or even death. That our body may contain a means to produce vitamin C -- perhaps small but still life-saving amounts -- makes intuitive sense, given the intelligence shot through the infinite complexity of Nature. And so, perhaps we are now only beginning to understand how much more energetic and biomolecular independence we have than conventional science has claimed we have.
