{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T06:56:19Z","timestamp":1790232979149,"version":"4.1.0"},"reference-count":33,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2017,6,13]],"date-time":"2017-06-13T00:00:00Z","timestamp":1497312000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["465357\/2014-8"],"award-info":[{"award-number":["465357\/2014-8"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001807","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de S\u00e3o Paulo","doi-asserted-by":"publisher","award":["2014\/509187"],"award-info":[{"award-number":["2014\/509187"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001807","name":"FAPESP","doi-asserted-by":"publisher","award":["2016\/16117-2"],"award-info":[{"award-number":["2016\/16117-2"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Diketopiperazines can be generated by non-enzymatic cyclization of linear dipeptides at extreme temperature or pH, and the complex medium used to culture bacteria and fungi including phytone peptone and trypticase peptone, can also produce cyclic peptides by heat sterilization. As a result, it is not always clear if many diketopiperazines reported in the literature are artifacts formed by the different complex media used in microorganism growth. An ideal method for analysis of these compounds should identify whether they are either synthesized de novo from the products of primary metabolism and deliver true diketopiperazines. A simple defined medium (X. fastidiosa medium or XFM) containing a single carbon source and no preformed amino acids has emerged as a method with a particularly high potential for the grown of X. fastidiosa and to produce genuine natural products. In this work, we identified a range of diketopiperazines from X. fastidiosa 9a5c growth in XFM, using Ultra-Fast Liquid Chromatography coupled with mass spectrometry. Diketopiperazines are reported for the first time from X. fastidiosa, which is responsible for citrus variegated chlorosis. We also report here fatty acids from X. fastidiosa, which were not biologically active as diffusible signals, and the role of diketopiperazines in signal transduction still remains unknown.<\/jats:p>","DOI":"10.3390\/molecules22060985","type":"journal-article","created":{"date-parts":[[2017,6,14]],"date-time":"2017-06-14T03:19:32Z","timestamp":1497410372000},"page":"985","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["A Simple Defined Medium for the Production of True Diketopiperazines in Xylella fastidiosa and Their Identification by Ultra-Fast Liquid Chromatography-Electrospray Ionization Ion Trap Mass Spectrometry"],"prefix":"10.3390","volume":"22","author":[{"given":"Michelli Massaroli da","family":"Silva","sequence":"first","affiliation":[{"name":"Departamento de Qu\u00edmica, Universidade Federal de S\u00e3o Carlos, CP 676, 13565-905 S\u00e3o Carlos-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2464-3687","authenticated-orcid":false,"given":"Moacir dos Santos","family":"Andrade","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Universidade Federal de S\u00e3o Carlos, CP 676, 13565-905 S\u00e3o Carlos-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anelize","family":"Bauermeister","sequence":"additional","affiliation":[{"name":"N\u00facleo Pesquisas em Produtos Naturais e Sint\u00e9ticos, Faculdade de Ci\u00eancias Farmac\u00eauticas de Ribeir\u00e3o Preto, Universidade de S\u00e3o Paulo, 14040-903 Ribeir\u00e3o Preto-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcus Vin\u00edcius","family":"Merfa","sequence":"additional","affiliation":[{"name":"Centro APTA Citros Sylvio Moreira, Instituto Agron\u00f4mico, CP 04, 13490-970 Cordeir\u00f3polis-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Moacir Rossi","family":"Forim","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Universidade Federal de S\u00e3o Carlos, CP 676, 13565-905 S\u00e3o Carlos-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9731-6172","authenticated-orcid":false,"given":"Jo\u00e3o Batista","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Universidade Federal de S\u00e3o Carlos, CP 676, 13565-905 S\u00e3o Carlos-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8159-3658","authenticated-orcid":false,"given":"Paulo Cezar","family":"Vieira","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Universidade Federal de S\u00e3o Carlos, CP 676, 13565-905 S\u00e3o Carlos-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7081-817X","authenticated-orcid":false,"given":"Maria F\u00e1tima das Gra\u00e7as Fernandes da","family":"Silva","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Universidade Federal de S\u00e3o Carlos, CP 676, 13565-905 S\u00e3o Carlos-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Norberto Peporine","family":"Lopes","sequence":"additional","affiliation":[{"name":"N\u00facleo Pesquisas em Produtos Naturais e Sint\u00e9ticos, Faculdade de Ci\u00eancias Farmac\u00eauticas de Ribeir\u00e3o Preto, Universidade de S\u00e3o Paulo, 14040-903 Ribeir\u00e3o Preto-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcos Ant\u00f4nio","family":"Machado","sequence":"additional","affiliation":[{"name":"Centro APTA Citros Sylvio Moreira, Instituto Agron\u00f4mico, CP 04, 13490-970 Cordeir\u00f3polis-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandra Alves de","family":"Souza","sequence":"additional","affiliation":[{"name":"Centro APTA Citros Sylvio Moreira, Instituto Agron\u00f4mico, CP 04, 13490-970 Cordeir\u00f3polis-SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,6,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"341","DOI":"10.1111\/j.1574-6968.2004.tb09716.x","article-title":"Gene expression profile of the plant pathogen Xylella fastidiosa during biofilm formation in vitro","volume":"237","author":"Souza","year":"2004","journal-title":"FEMS Microbiol. 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