{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T13:02:43Z","timestamp":1792501363776,"version":"4.5.0"},"reference-count":73,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,1,13]],"date-time":"2019-01-13T00:00:00Z","timestamp":1547337600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Protein fermentation by gut microbiota contributes significantly to the metabolite pool in the large intestine and may contribute to host amino acid balance. However, we have a limited understanding of the role that proteolytic metabolites have, both in the gut and in systemic circulation. A review of recent studies paired with findings from previous culture-based experiments suggests an important role for microbial protein fermentation in altering the gut microbiota and generating a diverse range of bioactive molecules which exert wide-ranging host effects. These metabolic products have been shown to increase inflammatory response, tissue permeability, and colitis severity in the gut. They are also implicated in the development of metabolic disease, including obesity, diabetes, and non-alcoholic fatty liver disease (NAFLD). Specific products of proteolytic fermentation such as hydrogen sulfide, ammonia, and p-Cresol may also contribute to the development of colorectal cancer. These findings are in conflict with other studies showing that tryptophan metabolites may improve gut barrier function and attenuate severity in a multiple sclerosis model. Further research examining proteolytic fermentation in the gut may be key to our understanding of how microbial and host metabolism interact affecting health.<\/jats:p>","DOI":"10.3390\/microorganisms7010019","type":"journal-article","created":{"date-parts":[[2019,1,14]],"date-time":"2019-01-14T12:20:07Z","timestamp":1547468407000},"page":"19","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":526,"title":["Microbial Fermentation of Dietary Protein: An Important Factor in Diet\u2013Microbe\u2013Host Interaction"],"prefix":"10.3390","volume":"7","author":[{"given":"Natalie E.","family":"Diether","sequence":"first","affiliation":[{"name":"Department of Agriculture, Food &amp; Nutritional Science, University of Alberta, Ag\/For Centre, Edmonton Alberta, T6G 2P5, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin P.","family":"Willing","sequence":"additional","affiliation":[{"name":"Department of Agriculture, Food &amp; Nutritional Science, University of Alberta, Ag\/For Centre, Edmonton Alberta, T6G 2P5, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1915","DOI":"10.1126\/science.1104816","article-title":"Host-bacterial mutualism in the human intestine","volume":"307","author":"Ley","year":"2005","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"497","DOI":"10.1038\/nrmicro3050","article-title":"The abundance and variety of carbohydrate-active enzymes in the human gut microbiota","volume":"11","author":"Kaoutari","year":"2013","journal-title":"Nat. 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