Abstract
Micronutrients cannot be synthesized by humans and are obtained from three different sources: diet, gut microbiota, and oral supplements. The microbiota generates significant quantities of micronutrients, but the contribution of these compounds to total uptake is unclear. The role of bacteria in the synthesis and uptake of micronutrients and supplements is widely unexplored and may have important implications for human health. The efficacy and safety of several micronutrient supplements, including folic acid, have been questioned due to some evidence of adverse effects on health. The use of the simplified animal-microbe model, Caenorhabditis elegans, and its bacterial food source, Escherichia coli, provides a controllable system to explore the underlying mechanisms by which bacterial metabolism impacts host micronutrient status. These studies have revealed mechanisms by which bacteria may increase the bioavailability of folic acid, B12, and iron. These routes of uptake interact with bacterial metabolism, with the potential to increase bacterial pathogenesis, and thus may be both beneficial and detrimental to host health.
Highlights
Bacterial folate is essential for C. elegans development and reproduction Folates are a family of interconvertible water-soluble molecules based on tetrahydrofolate (THF) (Fig. 2) and are used as enzymatic cofactors in a series of reactions known as one-carbon metabolism [38]
Implications for human health The advancement in metagenomic sequencing technologies has enabled the description of the micronutrient biosynthetic capacity of the human gut microbiota, but there is a substantial lack of mechanistic studies examining whether this contributes significantly to host micronutrient status and whether dietary and supplemental micronutrients interact with bacterial metabolism
While a simplified invertebrate model system cannot be used to make quantitative conclusions on human micronutrient demand and intake, it can be useful in understanding the qualitative mechanisms in which bacteria play a role in the provision of micronutrients and the effects that these have on health [63]
Summary
Bacterial, and supplemental micronutrients An array of essential vitamins and minerals, collectively known as micronutrients, is required to drive fundamental biosynthetic cellular reactions. Recent metagenomic studies have probed the B-vitamin biosynthetic capacity of the human gut microbiota and are consistent with a model in which micronutrients are exchanged between microbial producers and non-producers in synthesis and salvage pathways [8, 9] This exchange is predicted to play an important role in the stabilization of the microbial community and the maintenance of host-microbe homeostasis. Given the emerging importance of microbiota composition and stability on human health, combined with the impact of diet on bacterial metabolism, it is surprising that the interaction of the third absorbable source of micronutrients, oral supplements, with bacterial metabolism has not been considered. Studies using C. elegans have provided novel insights into how bacterial folate synthesis can be both beneficial and detrimental on host health depending on developmental stage and how bacteria act as conduits for folic acid, B12, and iron uptake.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
