{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,17]],"date-time":"2025-11-17T14:14:03Z","timestamp":1763388843452,"version":"build-2065373602"},"reference-count":59,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2013,9,30]],"date-time":"2013-09-30T00:00:00Z","timestamp":1380499200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Bacterial cell-to-cell communication (quorum sensing) refers to the regulation of bacterial gene expression in response to changes in microbial population density. Quorum sensing bacteria produce, release and respond to chemical signal molecules called autoinducers. Bacteria use two types of autoinducers, namely autoinducer-1 (AI-1) and autoinducer-2 (AI-2) where the former are N-acylhomoserine lactones and the latter is a product of the luxS gene. Most of the reported literatures show that the majority of oral bacteria use AI-2 for quorum sensing but rarely the AI-1 system. Here we report the isolation of Pseudomonas putida strain T2-2 from the oral cavity. Using high resolution mass spectrometry, it is shown that this isolate produced N-octanoylhomoserine lactone  (C8-HSL) and N-dodecanoylhomoserine lactone (C12-HSL) molecules. This is the first report of the finding of quorum sensing of P. putida strain T2-2 isolated from the human tongue surface and their quorum sensing molecules were identified.<\/jats:p>","DOI":"10.3390\/s131013192","type":"journal-article","created":{"date-parts":[[2013,9,30]],"date-time":"2013-09-30T12:22:30Z","timestamp":1380543750000},"page":"13192-13203","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["N-acyl Homoserine Lactone-Producing Pseudomonas putida Strain T2-2 from Human Tongue Surface"],"prefix":"10.3390","volume":"13","author":[{"given":"Jian-Woon","family":"Chen","sequence":"first","affiliation":[{"name":"Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shenyang","family":"Chin","sequence":"additional","affiliation":[{"name":"Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kok","family":"Tee","sequence":"additional","affiliation":[{"name":"Centre of Excellence for Research in AIDS (CERiA), Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wai-Fong","family":"Yin","sequence":"additional","affiliation":[{"name":"Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9891-5898","authenticated-orcid":false,"given":"Yeun","family":"Choo","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1883-1115","authenticated-orcid":false,"given":"Kok-Gan","family":"Chan","sequence":"additional","affiliation":[{"name":"Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,9,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6350","DOI":"10.1128\/JB.01642-12","article-title":"Draft genome sequence of an Aeromonas sp. strain 159 clinical isolate that shows quorum-sensing activity","volume":"194","author":"Chan","year":"2012","journal-title":"J. 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