{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,16]],"date-time":"2026-09-16T00:31:28Z","timestamp":1789518688063,"version":"build-2803163510"},"reference-count":35,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,12,19]],"date-time":"2025-12-19T00:00:00Z","timestamp":1766102400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"JSPS KAKENHI","award":["JP24K1310"],"award-info":[{"award-number":["JP24K1310"]}]},{"name":"JSPS KAKENHI","award":["JP22K17150"],"award-info":[{"award-number":["JP22K17150"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The oral cavity contains several microbial niches, including saliva, dental plaque and tongue coating, each shaped by distinct local environments and host factors. This study compared the ecological and functional characteristics of the microbiomes of these three oral sites within the same individuals and examined host conditions associated with their variation. Saliva, supragingival plaque and tongue coating samples were collected simultaneously from 31 adults without clinical oral lesions. The bacterial 16S rRNA gene (V3\u2013V4 region) was sequenced using the Illumina MiSeq platform, and analyses included \u03b1 and \u03b2 diversity, Mantel correlations, differential abundance tests, network analysis and functional prediction. The three sites displayed a clear ecological gradient. Saliva and tongue coating were taxonomically similar but were influenced by different host factors, whereas plaque maintained a distinct, biofilm-like structure with limited systemic influence. Functional divergence was most pronounced on the tongue coating despite its taxonomic similarity to saliva, whereas functional differences between saliva and plaque were modest despite larger taxonomic separation. These findings indicate that microbial composition and function vary independently across oral niches and support the need for multi-site sampling to more accurately characterize oral microbial ecology.<\/jats:p>","DOI":"10.3390\/microorganisms14010002","type":"journal-article","created":{"date-parts":[[2025,12,19]],"date-time":"2025-12-19T08:26:36Z","timestamp":1766132796000},"page":"2","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Ecological and Functional Landscape of the Oral Microbiome: A Multi-Site Analysis of Saliva, Dental Plaque and Tongue Coating"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1640-7094","authenticated-orcid":false,"given":"Toru","family":"Tamahara","sequence":"first","affiliation":[{"name":"Tohoku Medical Megabank Organization, Tohoku University, Sendai 980-8573, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6346-5441","authenticated-orcid":false,"given":"Atsumu","family":"Kouketsu","sequence":"additional","affiliation":[{"name":"Division of Oral and Maxillofacial Oncology and Surgical Sciences, Department of Disease Management Dentistry, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Satoshi","family":"Fukase","sequence":"additional","affiliation":[{"name":"Division of Oral and Maxillofacial Oncology and Surgical Sciences, Department of Disease Management Dentistry, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1726-1085","authenticated-orcid":false,"given":"Pawat","family":"Sripodok","sequence":"additional","affiliation":[{"name":"Division of Oral and Maxillofacial Oncology and Surgical Sciences, Department of Disease Management Dentistry, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Miyagi, Japan"},{"name":"Department of Oral and Maxillofacial Pathology, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tatsuru","family":"Saito","sequence":"additional","affiliation":[{"name":"Division of Oral and Maxillofacial Oncology and Surgical Sciences, Department of Disease Management Dentistry, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akiko","family":"Ito","sequence":"additional","affiliation":[{"name":"Division of Oral and Maxillofacial Oncology and Surgical Sciences, Department of Disease Management Dentistry, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bin","family":"Li","sequence":"additional","affiliation":[{"name":"Advanced Research Center for Innovations in Next-Generation Medicine, Tohoku University, Sendai 980-8573, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuki","family":"Kumada","sequence":"additional","affiliation":[{"name":"Advanced Research Center for Innovations in Next-Generation Medicine, Tohoku University, Sendai 980-8573, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1826-6723","authenticated-orcid":false,"given":"Muneaki","family":"Shimada","sequence":"additional","affiliation":[{"name":"Advanced Research Center for Innovations in Next-Generation Medicine, Tohoku University, Sendai 980-8573, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9255-2141","authenticated-orcid":false,"given":"Masahiro","family":"Iikubo","sequence":"additional","affiliation":[{"name":"Division of Dental Informatics and Radiology, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ritsuko","family":"Shimizu","sequence":"additional","affiliation":[{"name":"Tohoku Medical Megabank Organization, Tohoku University, Sendai 980-8573, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kensuke","family":"Yamauchi","sequence":"additional","affiliation":[{"name":"Division of Oral and Maxillofacial Reconstructive Surgery, Department of Disease Management Dentistry, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9964-1785","authenticated-orcid":false,"given":"Tsuyoshi","family":"Sugiura","sequence":"additional","affiliation":[{"name":"Division of Oral and Maxillofacial Oncology and Surgical Sciences, Department of Disease Management Dentistry, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Miyagi, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Saito, S., Aoki, Y., Tamahara, T., Goto, M., Matsui, H., Kawashima, J., Danjoh, I., Hozawa, A., Kuriyama, S., and Suzuki, Y. 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