REFERENCES
1. Bansil R, Turner BS. The biology of mucus: composition, synthesis and organization. Adv Drug Delivery Rev. 2018;124:3-15.
2. Johansson ME, Hansson GC. Immunological aspects of intestinal mucus and mucins. Nat Rev Immunol. 2016;16:639-49.
3. Johansson ME, Ambort D, Pelaseyed T, et al. Composition and functional role of the mucus layers in the intestine. Cell Mol Life Sci. 2011;68:3635-41.
4. Holmén Larsson JM, Thomsson KA, Rodríguez-Piñeiro AM, Karlsson H, Hansson GC. Studies of mucus in mouse stomach, small intestine, and colon. III. Gastrointestinal Muc5ac and Muc2 mucin O-glycan patterns reveal a regiospecific distribution. Am J Physiol Gastrointest Liver Physiol. 2013;305:G357-63.
5. Johansson ME, Phillipson M, Petersson J, Velcich A, Holm L, Hansson GC. The inner of the two Muc2 mucin-dependent mucus layers in colon is devoid of bacteria. Proc Natl Acad Sci U S A. 2008;105:15064-9.
6. de Ram C, van der Lugt B, Elzinga J, et al. Revealing glycosylation patterns in in vitro-produced mucus exposed to pasteurized mucus-associated intestinal microbes by MALDI-TOF-MS and PGC-LC-MS/MS. J Agric Food Chem. 2024;72:15345-56.
7. Zhao T, Zhang Y, Nan L, et al. Impact of structurally diverse polysaccharides on colonic mucin O-glycosylation and gut microbiota. NPJ Biofilms Microbiomes. 2023;9:97.
8. Pajic P, Shen S, Qu J, et al. A mechanism of gene evolution generating mucin function. Sci Adv. 2022;8:eabm8757.
9. Bergstrom K, Shan X, Casero D, et al. Proximal colon-derived O-glycosylated mucus encapsulates and modulates the microbiota. Science. 2020;370:467-72.
10. Recktenwald CV, Hansson GC. The reduction-insensitive bonds of the MUC2 mucin are isopeptide bonds. J Biol Chem. 2016;291:13580-90.
11. Tailford LE, Crost EH, Kavanaugh D, Juge N. Mucin glycan foraging in the human gut microbiome. Front Genet. 2015;6:81.
12. Jensen PH, Kolarich D, Packer NH. Mucin-type O-glycosylation - putting the pieces together. FEBS J. 2010;277:81-94.
13. Crost EH, Tailford LE, Le Gall G, Fons M, Henrissat B, Juge N. Utilisation of mucin glycans by the human gut symbiont Ruminococcus gnavus is strain-dependent. PLoS ONE. 2013;8:e76341.
14. Larsson JM, Karlsson H, Sjövall H, Hansson GC. A complex, but uniform O-glycosylation of the human MUC2 mucin from colonic biopsies analyzed by nanoLC/MSn. Glycobiology. 2009;19:756-66.
15. Bergstrom K, Fu J, Johansson ME, et al. Core 1- and 3-derived O-glycans collectively maintain the colonic mucus barrier and protect against spontaneous colitis in mice. Mucosal Immunol. 2017;10:91-103.
16. Hoskins LC, Boulding ET. Mucin degradation in human colon ecosystems. Evidence for the existence and role of bacterial subpopulations producing glycosidases as extracellular enzymes. J Clin Invest. 1981;67:163-72.
17. Miller RS, Hoskins LC. Mucin degradation in human colon ecosystems. Gastroenterology. 1981;81:759-65.
18. Taniguchi M, Okumura R, Matsuzaki T, et al. Sialylation shapes mucus architecture inhibiting bacterial invasion in the colon. Mucosal Immunol. 2023;16:624-41.
19. Gamage HKAH, Chong RWW, Bucio-Noble D, et al. Changes in dietary fiber intake in mice reveal associations between colonic mucin O-glycosylation and specific gut bacteria. Gut Microbes. 2020;12:1802209.
20. Yao Y, Kim G, Shafer S, et al. Mucus sialylation determines intestinal host-commensal homeostasis. Cell. 2022;185:1172-1188.e28.
21. Pruss KM, Marcobal A, Southwick AM, et al. Mucin-derived O-glycans supplemented to diet mitigate diverse microbiota perturbations. ISME J. 2021;15:577-91.
22. Arike L, Hansson GC. The densely O-glycosylated MUC2 mucin protects the intestine and provides food for the commensal bacteria. J Mol Biol. 2016;428:3221-9.
23. González-Morelo KJ, Vega-Sagardía M, Garrido D. Molecular insights into O-linked glycan utilization by gut microbes. Front Microbiol. 2020;11:591568.
24. Kostopoulos I, Aalvink S, Kovatcheva-Datchary P, et al. A continuous battle for host-derived glycans between a mucus specialist and a glycan generalist in vitro and in vivo. Front Microbiol. 2021;12:632454.
25. Glover JS, Ticer TD, Engevik MA. Characterizing the mucin-degrading capacity of the human gut microbiota. Sci Rep. 2022;12:8456.
26. Raimondi S, Musmeci E, Candeliere F, Amaretti A, Rossi M. Identification of mucin degraders of the human gut microbiota. Sci Rep. 2021;11:11094.
27. Bell A, Juge N. Mucosal glycan degradation of the host by the gut microbiota. Glycobiology. 2021;31:691-6.
28. Marcobal A, Southwick AM, Earle KA, Sonnenburg JL. A refined palate: bacterial consumption of host glycans in the gut. Glycobiology. 2013;23:1038-46.
29. Mutagenesis reveals how Akkermansia muciniphila degrades mucin and colonizes the gut. Nat Microbiol. 2023;8:1384-5.
30. Qu S, Zheng Y, Huang Y, et al. Excessive consumption of mucin by over-colonized Akkermansia muciniphila promotes intestinal barrier damage during malignant intestinal environment. Front Microbiol. 2023;14:1111911.
31. Hayase E, Hayase T, Jamal MA, et al. Mucus-degrading Bacteroides link carbapenems to aggravated graft-versus-host disease. Cell. 2022;185:3705-3719.e14.
32. Schaus SR, Vasconcelos Pereira G, Luis AS, et al. Ruminococcus torques is a keystone degrader of intestinal mucin glycoprotein, releasing oligosaccharides used by Bacteroides thetaiotaomicron. mBio. 2024;15:e0003924.
33. Salyers AA, Vercellotti JR, West SE, Wilkins TD. Fermentation of mucin and plant polysaccharides by strains of Bacteroides from the human colon. Appl Environ Microbiol. 1977;33:319-22.
34. Davey LE, Malkus PN, Villa M, et al. A genetic system for Akkermansia muciniphila reveals a role for mucin foraging in gut colonization and host sterol biosynthesis gene expression. Nat Microbiol. 2023;8:1450-67.
35. Culp EJ, Goodman AL. Cross-feeding in the gut microbiome: ecology and mechanisms. Cell Host Microbe. 2023;31:485-99.
36. Tingler AM, Engevik MA. Breaking down barriers: is intestinal mucus degradation by Akkermansia muciniphila beneficial or harmful? Infect Immun. 2025;93:e0050324.
37. Berkhout MD, Plugge CM, Belzer C. How microbial glycosyl hydrolase activity in the gut mucosa initiates microbial cross-feeding. Glycobiology. 2022;32:182-200.
38. Engevik MA, Engevik AC, Engevik KA, et al. Mucin-degrading microbes release monosaccharides that chemoattract Clostridioides difficile and facilitate colonization of the human intestinal mucus layer. ACS Infect Dis. 2021;7:1126-42.
39. Burger-van Paassen N, Vincent A, Puiman PJ, et al. The regulation of intestinal mucin MUC2 expression by short-chain fatty acids: implications for epithelial protection. Biochem J. 2009;420:211-9.
40. Gaudier E, Jarry A, Blottière HM, et al. Butyrate specifically modulates MUC gene expression in intestinal epithelial goblet cells deprived of glucose. Am J Physiol Gastrointest Liver Physiol. 2004;287:G1168-74.
41. Belzer C, Chia LW, Aalvink S, et al. Microbial metabolic networks at the mucus layer lead to diet-independent butyrate and vitamin B12 production by intestinal symbionts. mBio. 2017;8:e00770-17.
42. Chia LW, Hornung BVH, Aalvink S, et al. Deciphering the trophic interaction between Akkermansia muciniphila and the butyrogenic gut commensal Anaerostipes caccae using a metatranscriptomic approach. Antonie Van Leeuwenhoek. 2018;111:859-73.
43. Shuoker B, Pichler MJ, Jin C, et al. Sialidases and fucosidases of Akkermansia muciniphila are crucial for growth on mucin and nutrient sharing with mucus-associated gut bacteria. Nat Commun. 2023;14:1833.
44. El Hage R, Hernandez-Sanabria E, Calatayud Arroyo M, Props R, Van de Wiele T. Propionate-producing consortium restores antibiotic-induced dysbiosis in a dynamic in vitro model of the human intestinal microbial ecosystem. Front Microbiol. 2019;10:1206.
45. Bunesova V, Lacroix C, Schwab C. Mucin cross-feeding of infant bifidobacteria and eubacterium hallii. Microb Ecol. 2018;75:228-38.
46. Cantarel BL, Coutinho PM, Rancurel C, Bernard T, Lombard V, Henrissat B. The Carbohydrate-Active EnZymes database (CAZy): an expert resource for glycogenomics. Nucleic Acids Res. 2009;37:D233-8.
47. El Kaoutari A, Armougom F, Gordon JI, Raoult D, Henrissat B. The abundance and variety of carbohydrate-active enzymes in the human gut microbiota. Nat Rev Microbiol. 2013;11:497-504.
48. Lombard V, Golaconda Ramulu H, Drula E, Coutinho PM, Henrissat B. The carbohydrate-active enzymes database (CAZy) in 2013. Nucleic Acids Res. 2014;42:D490-5.
49. Park BH, Karpinets TV, Syed MH, Leuze MR, Uberbacher EC. CAZymes Analysis Toolkit (CAT): web service for searching and analyzing carbohydrate-active enzymes in a newly sequenced organism using CAZy database. Glycobiology. 2010;20:1574-84.
50. Henrissat B, Bairoch A. New families in the classification of glycosyl hydrolases based on amino acid sequence similarities. Biochem J. 1993;293 ( Pt 3):781-8.
51. Henrissat B. A classification of glycosyl hydrolases based on amino acid sequence similarities. Biochem J. 1991;280 ( Pt 2):309-16.
52. Zhang G, Mills DA, Block DE. Development of chemically defined media supporting high-cell-density growth of lactococci, enterococci, and streptococci. Appl Environ Microbiol. 2009;75:1080-7.
53. Horvath TD, Haidacher SJ, Engevik MA, et al. Interrogation of the mammalian gut-brain axis using LC-MS/MS-based targeted metabolomics with in vitro bacterial and organoid cultures and in vivo gnotobiotic mouse models. Nat Protoc. 2023;18:490-529.
54. Engevik KA, Gonzalez H, Daniels C, et al. A high-throughput protocol for measuring solution pH of bacterial cultures using UV-Vis absorption spectrophotometry. STAR Protoc. 2023;4:102540.
55. Ticer TD, Tingler AM, Glover JS, et al. Bacterial metabolites influence the autofluorescence of Clostridioides difficile. Front Microbiol. 2024;15:1459795.
57. Chen Y, Xu J, Chen Y. Regulation of neurotransmitters by the gut microbiota and effects on cognition in neurological disorders. Nutrients. 2021;13:2099.
58. Pokusaeva K, Johnson C, Luk B, et al. GABA-producing Bifidobacterium dentium modulates visceral sensitivity in the intestine. Neurogastroenterol Motil. 2017;29:e12904.
59. Cui Y, Miao K, Niyaphorn S, Qu X. Production of gamma-aminobutyric acid from lactic acid bacteria: a systematic review. Int J Mol Sci. 2020;21:995.
60. Yunes RA, Poluektova EU, Dyachkova MS, et al. GABA production and structure of gadB/gadC genes in Lactobacillus and Bifidobacterium strains from human microbiota. Anaerobe. 2016;42:197-204.
61. Villageliú D, Lyte M. Dopamine production in Enterococcus faecium: a microbial endocrinology-based mechanism for the selection of probiotics based on neurochemical-producing potential. PLoS ONE. 2018;13:e0207038.
62. Yano JM, Yu K, Donaldson GP, et al. Indigenous bacteria from the gut microbiota regulate host serotonin biosynthesis. Cell. 2015;161:264-76.
63. Williams BB, Van Benschoten AH, Cimermancic P, et al. Discovery and characterization of gut microbiota decarboxylases that can produce the neurotransmitter tryptamine. Cell Host Microbe. 2014;16:495-503.
64. Tingler AM, Packirisamy C, Guterriez A, et al. Commensal human gut microbes produce species specific neuro-active compounds. iScience. 2025:114424.
65. Salvi PS, Cowles RA. Butyrate and the intestinal epithelium: modulation of proliferation and inflammation in homeostasis and disease. Cells 2021;10:1755.
66. Yoshida A, Yoshimura M, Ohara N, et al. Hydrogen sulfide production from cysteine and homocysteine by periodontal and oral bacteria. J Periodontol. 2009;80:1845-51.
67. Motta JP, Flannigan KL, Agbor TA, et al. Hydrogen sulfide protects from colitis and restores intestinal microbiota biofilm and mucus production. Inflamm Bowel Dis. 2015;21:1006-17.
68. Teufel R, Mascaraque V, Ismail W, et al. Bacterial phenylalanine and phenylacetate catabolic pathway revealed. Proc Natl Acad Sci USA. 2010;107:14390-5.
69. Saito Y, Sato T, Nomoto K, Tsuji H. Identification of phenol- and p-cresol-producing intestinal bacteria by using media supplemented with tyrosine and its metabolites. FEMS Microbiol Ecol. 2018;94:fiy125.
70. Mu Q, Shi Y, Li R, Ma C, Tao Y, Yu B. Production of propionate by a sequential fermentation-biotransformation process via l-threonine. J Agric Food Chem. 2021;69:13895-903.
71. Cheng ZX, Guo C, Chen ZG, et al. Glycine, serine and threonine metabolism confounds efficacy of complement-mediated killing. Nat Commun. 2019;10:3325.
72. Loeza-Alcocer E, McPherson TP, Gold MS. Peripheral GABA receptors regulate colonic afferent excitability and visceral nociception. J Physiol. 2019;597:3425-39.
73. Gros M, Gros B, Mesonero JE, Latorre E. Neurotransmitter dysfunction in irritable bowel syndrome: emerging approaches for management. J Clin Med. 2021;10:3429.
74. Auteri M, Zizzo MG, Serio R. GABA and GABA receptors in the gastrointestinal tract: from motility to inflammation. Pharmacol Res. 2015;93:11-21.
75. Deng Z, Li D, Yan X, et al. Activation of GABA receptor attenuates intestinal inflammation by modulating enteric glial cells function through inhibiting NF-κB pathway. Life Sci. 2023;329:121984.
76. Liao Y, Fan L, Bin P, et al. GABA signaling enforces intestinal germinal center B cell differentiation. Proc Natl Acad Sci USA. 2022;119:e2215921119.
77. Ren W, Yin J, Xiao H, et al. Intestinal microbiota-derived GABA mediates interleukin-17 expression during enterotoxigenic Escherichia coli infection. Front Immunol. 2016;7:685.
78. Gomes P, Laroute V, Beaufrand C, et al. Lactococcus lactis CNCM I-5388 versus NCDO2118 by its GABA hyperproduction ability, counteracts faster stress-induced intestinal hypersensitivity in rats. FASEB J. 2023;37:e23264.
79. Laroute V, Aubry N, Audonnet M, Mercier-Bonin M, Daveran-Mingot ML, Cocaign-Bousquet M. Natural diversity of lactococci in γ-aminobutyric acid (GABA) production and genetic and phenotypic determinants. Microb Cell Fact. 2023;22:178.
80. Horvath TD, Ihekweazu FD, Haidacher SJ, et al. Bacteroides ovatus colonization influences the abundance of intestinal short chain fatty acids and neurotransmitters. iScience. 2022;25:104158.
81. Luck B, Horvath TD, Engevik KA, et al. Neurotransmitter profiles are altered in the gut and brain of mice mono-associated with Bifidobacterium dentium. Biomolecules. 2021;11:1091.
82. Otaru N, Ye K, Mujezinovic D, et al. GABA production by human intestinal Bacteroides spp.: prevalence, regulation, and role in acid stress tolerance. Front Microbiol. 2021;12:656895.
83. Konstanti P, Ligthart K, Fryganas C, et al. Physiology of γ-aminobutyric acid production by Akkermansia muciniphila. Appl Environ Microbiol. 2024;90:e0112123.
84. Yunes RA, Poluektova EU, Vasileva EV, et al. A multi-strain potential probiotic formulation of GABA-producing Lactobacillus plantarum 90sk and Bifidobacterium adolescentis 150 with antidepressant effects. Probiotics Antimicrob Proteins. 2020;12:973-9.
85. Duranti S, Ruiz L, Lugli GA, et al. Bifidobacterium adolescentis as a key member of the human gut microbiota in the production of GABA. Sci Rep. 2020;10:14112.
86. Wang D, Jiang Y, Jiang J, et al. Gut microbial GABA imbalance emerges as a metabolic signature in mild autism spectrum disorder linked to overrepresented Escherichia. Cell Rep Med. 2025;6:101919.
87. Sharafi S, Nateghi L, Yousefi S. Investigating the effect of pH, different concentrations of glutamate acid and salt on production in low-fat probiotic cheese. Iran J Microbiol. 2021;13:389-98.
88. Dhakal R, Bajpai VK, Baek KH. Production of gaba (γ-Aminobutyric acid) by microorganisms: a review. Braz J Microbiol. 2012;43:1230-41.
89. Raethong N, Chamtim P, Thananusak R, Whanmek K, Santivarangkna C. Genome-wide transcriptomics revealed carbon source-mediated gamma-aminobutyric acid (GABA) production in a probiotic, Lactiplantibacillus pentosus 9D3. Heliyon. 2025;11:e41879.
90. Song HY, Yu RC. Optimization of culture conditions for gamma-aminobutyric acid production in fermented adzuki bean milk. J Food Drug Anal. 2018;26:74-81.
91. Hussin FS, Chay SY, Hussin ASM, et al. GABA enhancement by simple carbohydrates in yoghurt fermented using novel, self-cloned Lactobacillus plantarum Taj-Apis362 and metabolomics profiling. Sci Rep. 2021;11:9417.
92. Chai Y, Zheng W, Hu S, Yang T, Chen G, Huang A. Novel molecular mechanisms of gamma-aminobutyric acid production mediated by LuxS/AI-2 quorum sensing system in Limosilactobacillus fermentum B41. Int J Food Microbiol. 2025;439:111269.
93. Werlang CA, Chen WG, Aoki K, et al. Mucin O-glycans suppress quorum-sensing pathways and genetic transformation in Streptococcus mutans. Nat Microbiol. 2021;6:574-83.
94. Wheeler KM, Gold MA, Stevens CA, et al. Mucus-derived glycans are inhibitory signals for Salmonella Typhimurium SPI-1-mediated invasion. Cell Rep. 2025;44:116304.
95. Ding X, Robbe-Masselot C, Fu X, et al. Airway environment drives the selection of quorum sensing mutants and promote Staphylococcus aureus chronic lifestyle. Nat Commun. 2023;14:8135.
96. Jacob KM, Hernández-Villamizar S, Hammer ND, Reguera G. Mucin-induced surface dispersal of Staphylococcus aureus and Staphylococcus epidermidis via quorum-sensing dependent and independent mechanisms. mBio. 2024;15:e0156224.
97. Budnick JA, Sheehan LM, Benton AH, et al. Characterizing the transport and utilization of the neurotransmitter GABA in the bacterial pathogen Brucella abortus. PLoS ONE. 2020;15:e0237371.
98. Quillin SJ, Tran P, Prindle A. Potential roles for gamma-aminobutyric acid signaling in bacterial communities. Bioelectricity. 2021;3:120-5.
99. Dover S, Halpern YS. Utilization of -aminobutyric acid as the sole carbon and nitrogen source by Escherichia coli K-12 mutants. J Bacteriol. 1972;109:835-43.
100. Feehily C, Karatzas KA. Role of glutamate metabolism in bacterial responses towards acid and other stresses. J Appl Microbiol. 2013;114:11-24.
101. Park HB, Song D, Nguyen M, Palm NW, Crawford JM. Tryptamine metabolism and functionalization in gut commensal bacteria expand human tryptamine signaling responses. ACS Chem Biol. 2025;20:1775-82.
102. Otaru N, Greppi A, Plüss S, et al. Intestinal bacteria-derived tryptamine and its impact on human gut microbiota. Front Microbiomes. 2024;3:1373335.
103. Zhai L, Xiao H, Lin C, et al. Gut microbiota-derived tryptamine and phenethylamine impair insulin sensitivity in metabolic syndrome and irritable bowel syndrome. Nat Commun. 2023;14:4986.
104. Park HB, Song D, Nguyen M, Palm NW, Crawford JM. Tryptamine metabolism and functionalization in gut commensal bacteria expand human tryptamine signaling responses. ACS Chem Biol. 2025;20:1775-82.
105. Blough BE, Landavazo A, Decker AM, Partilla JS, Baumann MH, Rothman RB. Interaction of psychoactive tryptamines with biogenic amine transporters and serotonin receptor subtypes. Psychopharmacology (Berl). 2014;231:4135-44.
106. Bhattarai Y, Williams BB, Battaglioli EJ, et al. Gut microbiota-produced tryptamine activates an epithelial G-protein-coupled receptor to increase colonic secretion. Cell Host Microbe. 2018;23:775-785.e5.
107. Khan MZ, Nawaz W. The emerging roles of human trace amines and human trace amine-associated receptors (hTAARs) in central nervous system. Biomed Pharmacother. 2016;83:439-49.
108. Bugda Gwilt K, González DP, Olliffe N, et al. Actions of trace amines in the brain-gut-microbiome axis via trace amine-associated receptor-1 (TAAR1). Cell Mol Neurobiol. 2020;40:191-201.
109. Padra M, Adamczyk B, Benktander J, et al. Helicobacter suis binding to carbohydrates on human and porcine gastric mucins and glycolipids occurs via two modes. Virulence. 2018;9:898-918.
110. Karlsson NG, Nordman H, Karlsson H, Carlstedt I, Hansson GC. Glycosylation differences between pig gastric mucin populations: a comparative study of the neutral oligosaccharides using mass spectrometry. Biochem J. 1997;326 ( Pt 3):911-7.
111. Nordman H, Davies JR, Herrmann A, et al. Mucus glycoproteins from pig gastric mucosa: identification ofdifferent mucin populations from the surface epithelium. Biochem J. 1997;326 ( Pt 3):903-10.
112. Jin C, Kenny DT, Skoog EC, et al. Structural diversity of human gastric mucin glycans. Mol Cell Proteomics. 2017;16:743-58.
113. Venkatakrishnan V, Quintana-Hayashi MP, Mahu M, Haesebrouck F, Pasmans F, Lindén SK. Brachyspira hyodysenteriae infection regulates mucin glycosylation synthesis inducing an increased expression of core-2 O-glycans in porcine colon. J Proteome Res. 2017;16:1728-42.
114. Marshall T, Allen A. The isolation and characterization of the high-molecular-weight glycoprotein from pig colonic mucus. Biochem J. 1978;173:569-78.
115. Thomsson KA, Holmén-Larsson JM, Angström J, Johansson ME, Xia L, Hansson GC. Detailed O-glycomics of the Muc2 mucin from colon of wild-type, core 1- and core 3-transferase-deficient mice highlights differences compared with human MUC2. Glycobiology. 2012;22:1128-39.
116. Robbe C, Capon C, Coddeville B, Michalski JC. Structural diversity and specific distribution of O-glycans in normal human mucins along the intestinal tract. Biochem J. 2004;384:307-16.
117. Kasahara K, Krautkramer KA, Org E, et al. Interactions between Roseburia intestinalis and diet modulate atherogenesis in a murine model. Nat Microbiol. 2018;3:1461-71.
118. Pichler MJ, Yamada C, Shuoker B, et al. Butyrate producing colonic Clostridiales metabolise human milk oligosaccharides and cross feed on mucin via conserved pathways. Nat Commun. 2020;11:3285.
119. Lu H, Xu X, Fu D, et al. Butyrate-producing Eubacterium rectale suppresses lymphomagenesis by alleviating the TNF-induced TLR4/MyD88/NF-κB axis. Cell Host Microbe. 2022;30:1139-1150.e7.
120. Kim H, Jeong Y, Kang S, You HJ, Ji GE. Co-culture with bifidobacterium catenulatum improves the growth, gut colonization, and butyrate production of Faecalibacterium prausnitzii: in vitro and in vivo studies. Microorganisms. 2020;8:788.
121. Khan MT, Duncan SH, Stams AJ, van Dijl JM, Flint HJ, Harmsen HJ. The gut anaerobe Faecalibacterium prausnitzii uses an extracellular electron shuttle to grow at oxic-anoxic interphases. ISME J. 2012;6:1578-85.
122. Crost EH, Tailford LE, Monestier M, et al. The mucin-degradation strategy of Ruminococcus gnavus: the importance of intramolecular trans-sialidases. Gut Microbes. 2016;7:302-12.






