{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T02:18:45Z","timestamp":1790216325096,"version":"4.1.0"},"reference-count":58,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2022,6,2]],"date-time":"2022-06-02T00:00:00Z","timestamp":1654128000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["R01 DK107561"],"award-info":[{"award-number":["R01 DK107561"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Dairy Council, and the University of Illinois Division of Nutritional Sciences Margin of Excellence fund","award":["R01 DK107561"],"award-info":[{"award-number":["R01 DK107561"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Infancy is a critical life stage for the establishment of the gut microbiome. Human milk contains a unique microbial ecosystem that serves as a continuous source of commensal bacteria for the infant. However, the origin of the human milk microbiota, how it is influenced by breastfeeding exclusivity, and its role in infant gut microbiota assembly are not clear. To interrogate these questions, we examined the relationships among fecal, oral, breast skin, and human milk microbiota of 33 exclusively breastfeeding (EBF) and mixed-feeding (MF; human milk + infant formula) mother\u2013infant pairs at 6 weeks postpartum. Here, we show that MF infants have a significantly more diverse oral microbiome comprised of lower relative abundances of Streptococcus and Gemella and higher abundances of Veillonella. Using both SourceTracker2 and FEAST, we demonstrate breast skin and infant saliva as the principal contributing sources to the human milk microbiota. Of the sampled sites, human milk and maternal stool were predicted to contribute the largest fraction to the infant fecal microbiome, but the majority of the community was estimated to arise from unknown sources. Lastly, we identified twenty-one significant co-occurrence relationships between bacteria in human milk and on other maternal and infant body sites. These results demonstrate several unique microbial interrelationships between breastfeeding dyads, providing insight into potential mechanisms of microbial assembly in early life.<\/jats:p>","DOI":"10.3390\/microorganisms10061155","type":"journal-article","created":{"date-parts":[[2022,6,2]],"date-time":"2022-06-02T11:05:02Z","timestamp":1654167902000},"page":"1155","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Microbial Interrelationships across Sites of Breastfeeding Mothers and Infants at 6 Weeks Postpartum"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4599-1632","authenticated-orcid":false,"given":"Erin C.","family":"Davis","sequence":"first","affiliation":[{"name":"Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0379-6633","authenticated-orcid":false,"given":"Mei","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Food Science and Human Nutrition, University of Illinois, Urbana, IL 61801, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9785-4189","authenticated-orcid":false,"given":"Sharon M.","family":"Donovan","sequence":"additional","affiliation":[{"name":"Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801, USA"},{"name":"Department of Food Science and Human Nutrition, University of Illinois, Urbana, IL 61801, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"380","DOI":"10.1016\/j.siny.2016.04.004","article-title":"Impact of early gut microbiota on immune and metabolic development and function","volume":"21","author":"Wang","year":"2016","journal-title":"Semin. 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