{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T06:04:46Z","timestamp":1789452286315,"version":"build-2803163510"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:00:00Z","timestamp":1789430400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>\n                      Citrus huanglongbing (HLB), caused by\n                      <jats:italic>Candidatus<\/jats:italic>\n                      Liberibacter asiaticus (CLas), is a globally devastating plant disease characterized by severe disruption of host physiology. Although alterations in plant hormone homeostasis, including salicylic acid and abscisic acid (ABA), are hallmarks of HLB, the contribution of plant-associated microbiota to these hormonal changes remains poorly understood. Here, we investigated whether ABA depletion in HLB-affected citrus is associated with microbial metabolism.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      ABA and its metabolites were quantified in HLB-affected citrus tissues by liquid chromatography\u2013mass spectrometry. The capacity of CLas strain Ishi-1 and\n                      <jats:italic>Flavobacterium<\/jats:italic>\n                      spp. strains CGRL1 and CGRL2 to metabolize ABA was assessed using\n                      <jats:italic>in vitro<\/jats:italic>\n                      culture assays. The effects of exogenous ABA on bacterial growth were also evaluated.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      ABA concentrations were significantly decreased in symptomatic HLB-affected tissues, concomitant with the accumulation of the ABA catabolite dehydrovomifoliol. Furthermore, CLas strain Ishi-1 and\n                      <jats:italic>Flavobacterium<\/jats:italic>\n                      strains CGRL1 and CGRL2 degraded ABA and produced dehydrovomifoliol, whereas no such activity was detected in non-inoculated controls. Notably, exogenous ABA promoted bacterial growth, suggesting that ABA may serve as a metabolic substrate or growth-enhancing factor for these bacteria.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>These findings identify microbial ABA metabolism as a potential driver of hormone depletion in HLB-affected citrus. Our results further suggest that CLas and its associated bacteria may actively reshape host hormone homeostasis through ABA metabolism, providing a mechanistic link between pathogen-associated microbial communities and hormonal imbalance during HLB development.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmicb.2026.1940325","type":"journal-article","created":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T05:36:33Z","timestamp":1789450593000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Abscisic acid metabolism to dehydrovomifoliol by Candidatus Liberibacter asiaticus and CLas-associated Flavobacterium strains CGRL1 and CGRL2"],"prefix":"10.3389","volume":"17","author":[{"given":"Kosuke","family":"Yamada","sequence":"first","affiliation":[{"name":"Graduate School of Agriculture, Meijo University","place":["Nagoya, Aichi, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Azusa","family":"Fukushima","sequence":"additional","affiliation":[{"name":"Graduate School of Agriculture, Meijo University","place":["Nagoya, Aichi, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takashi","family":"Fujikawa","sequence":"additional","affiliation":[{"name":"Institute for Plant Protection, National Agriculture and Food Research Organization (NARO)","place":["Tsukuba, Ibaraki, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroyuki","family":"Nakagawa","sequence":"additional","affiliation":[{"name":"Research Center for Advanced Analysis, Core Technology Research Headquarters, National Agriculture and Food Research Organization (NARO)","place":["Tsukuba, Ibaraki, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kosuke","family":"Namba","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Graduate School of Science, The University of Osaka","place":["Toyonaka, Osaka, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuki","family":"Fujiwara","sequence":"additional","affiliation":[{"name":"Graduate School of Agriculture, Meijo University","place":["Nagoya, Aichi, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,15]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"931","DOI":"10.1002\/hlca.19880710502","article-title":"Synthese von enantiomerenreinen Violaxanthinen und verwandten Verbindungen","volume":"71","author":"Acemoglu","year":"1988","journal-title":"Helv. 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