Fermentation

For other uses, see Fermentation (disambiguation).
Not to be confused with Anaerobic respiration.

Phylogenetic tree of bacteria and archaea, highlighting those that carry out fermentation. Their end products are also highlighted. Figure modified from Hackmann (2024).[1]

Fermentation is a type of redox metabolism carried out in the absence of oxygen.[1][2] During fermentation, organic molecules (e.g., glucose) are catabolized and donate electrons to other organic molecules. In the process, ATP and organic end products (e.g., lactate) are formed.

Because oxygen is not required, it is an alternative to aerobic respiration. Over 25% of bacteria and archaea carry out fermentation.[2][3] They live in the gut, sediments, food, and other environments. Eukaryotes, including humans and other animals, also carry out fermentation.[4]

Fermentation is important in several areas of human society.[2] Humans have used fermentation in production of food for 13,000 years.[5] Humans and their livestock have microbes in the gut that carry out fermentation, releasing products used by the host for energy.[6] Fermentation is used at an industrial level to produce commodity chemicals, such as ethanol and lactate. In total, fermentation forms more than 50 metabolic end products[2] with a wide range of uses.

  1. ^ a b Hackmann TJ (June 2024). "The vast landscape of carbohydrate fermentation in prokaryotes". FEMS Microbiology Reviews. 48 (4): fuae016. doi:10.1093/femsre/fuae016. PMC 11187502. PMID 38821505.
  2. ^ a b c d Hackmann TJ, Zhang B (September 2023). "The phenotype and genotype of fermentative prokaryotes". Science Advances. 9 (39): eadg8687. Bibcode:2023SciA....9G8687H. doi:10.1126/sciadv.adg8687. PMC 10530074. PMID 37756392.
  3. ^ Hackmann TJ, Zhang B (March 2021). "Using neural networks to mine text and predict metabolic traits for thousands of microbes". PLOS Computational Biology. 17 (3): e1008757. Bibcode:2021PLSCB..17E8757H. doi:10.1371/journal.pcbi.1008757. PMC 7954334. PMID 33651810.
  4. ^ Müller M, Mentel M, van Hellemond JJ, Henze K, Woehle C, Gould SB, et al. (June 2012). "Biochemistry and evolution of anaerobic energy metabolism in eukaryotes". Microbiology and Molecular Biology Reviews. 76 (2): 444–495. doi:10.1128/MMBR.05024-11. PMC 3372258. PMID 22688819.
  5. ^ Liu L, Wang J, Rosenberg D, Zhao H, Lengyel G, Nadel D (2018). "Fermented beverage and food storage in 13,000 y-old stone mortars at Raqefet Cave, Israel: Investigating Natufian ritual feasting". Journal of Archaeological Science: Reports. 21: 783–793. doi:10.1016/j.jasrep.2018.06.011.
  6. ^ Bergman EN (April 1990). "Energy contributions of volatile fatty acids from the gastrointestinal tract in various species". Physiological Reviews. 70 (2): 567–590. doi:10.1152/physrev.1990.70.2.567. PMID 2181501.