Microbial Diversity phase 2

Importance of Microbial Diversity

MICROBIAL DIVERSITY

Microbial volume and diversity is essential.

The gut microbiome—the microbial community in the intestinal tract—is an influencer of metabolism and immunity and a mediator of resistance to some pathogenic infections.1

Microbiome visual

A distinct and essential organ within the human body, the gut microbiome contains an estimated 500-1000 species and 100 trillion organisms, encoding 100-fold more unique genes than our own genome.1-4

In its balanced state, there is a symbiotic relationship between luminal bacteria and our human cells.5

These cells communicate and form long-lasting, interactive associations that play a vital role in conservation of mucosal immune function, epithelial barrier integrity, motility, and nutrient absorption.5-7

Bacteroidetes and Firmicutes are most prevalent in the gut microbime and work symbiotically8-10

Bacteroides

Gram-negative Bacteroidetes
Their ability to adapt and persist in changing gut environments allows abundance and stability,8,11-13 providing long-term associations with human hosts and enabling functions that include8..

  • Immunomodulatory effects8,a
  • Inhibitory activities against C. diff and reduction of colonization14,a,b
Firmicutes

Gram-positive Firmicutes
Composed of helpful and harmful bacteria,2,15 Firmicutes are the most abundant and diverse bacterial gut species,2 with functions that include:

  • Anti-inflammatory effects16-18,c
  • Fortification of gut barrier (along with other bacteria)19-21,b

Deficiencies in Bacteroidetes and Firmicutes are particularly associated with C. diff infection.2,9,22

aSome Bacteroidetes.

bIn preclinical studies.

cDemonstrated in Crohn's disease, inflammatory bowel disease, and ulcerative colitis studies.

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References

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  2. Antharam VC, Li EC, Ishmael A, et al. Intestinal dysbiosis and depletion of butyrogenic bacteria in Clostridium difficile infection and nosocomial diarrhea. J Clin Microbiol. 2013;51(9):2884-2892.
  3. Thursby E, Juge N. Introduction to the human gut microbiota. Biochem J. 2017;474(11):1823-1836.
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  10. Nishijima S, Suda W, Oshima K, et al. The gut microbiome of healthy Japanese and its microbial and functional uniqueness. DNA Res. 2016;23(2)(Suppl Table S6).
    https://academic.oup.com/dnaresearch/article/23/2/125/1745357#supplementary-data. Accessed September 5, 2021.
  11. Gill SR, Pop M, Deboy RT, et al. Metagenomic analysis of the human distal gut microbiome. Science. 2006;312(5778):1355-1359.
  12. Kurokawa K, Itoh T, Kuwahara T, et al. Comparative metagenomics revealed commonly enriched gene sets in human gut microbiomes. DNA Res. 2007;14(4):169-181.
  13. Faith JJ, Guruge JL, Charbonneau M, et al. The long-term stability of the human gut microbiota. Science. 2013;341(6141):1237439.
  14. Li X, Kang Y, Huang Y, et al. A strain of Bacteroides thetaiotaomicron attenuates colonization of Clostridioides difficile and affects intestinal microbiota and bile acids profile in a mouse model. Biomed Pharmacother. 2021;137:111290.
  15. Kho ZY, Lal SK. The human gut microbiome—a potential controller of wellness and disease. Front Microbiol. 2018;9:1835.
  16. Sokol H, Pigneur B, Watterlot L, et al. Faecalibacterium prausnitzii is an anti-inflammatory commensal bacterium identified by gut microbiota analysis of Crohn disease patients. Proc Natl Acad Sci U S A. 2008;105(43):16731-16736.
  17. Willing BP, Dicksved J, Halfvarson J, et al. A pyrosequencing study in twins shows that gastrointestinal microbial profiles vary with inflammatory bowel disease phenotypes. Gastroenterology. 2010;139(6):1844-1854.e1.
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  19. Paust S, Lu L, Mccarty N, Cantor H. Engagement of B7 on effector T cells by regulatory T cells prevents autoimmune disease. Proc Natl Acad Sci U S A. 2004;101(28):10398-10403.
  20. El Aidy S, van Baarlen P, Derrien M, et al. Temporal and spatial interplay of microbiota and intestinal mucosa drive establishment of immune homeostasis in conventionalized mice. Mucosal Immunol. 2012;5(5):567-579.
  21. Lawley TD, Walker AW. Intestinal colonization resistance. Immunology. 2013;138(1):1-11.
  22. Martens EC, Koropatkin NM, Smith TJ, Gordon JI. Complex glycan catabolism by the human gut microbiota: the bacteroidetes Sus-like paradigm. J Biol Chem. 2009;284(37):24673-24677.