{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:33:13Z","timestamp":1787790793297,"version":"build-2784847793"},"reference-count":37,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T00:00:00Z","timestamp":1782777600000},"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. Cell. Infect. Microbiol."],"abstract":"<jats:p>\n                    Necrotizing soft tissue infections (NSTIs) are fulminant bacterial diseases characterized by rapid tissue destruction, systemic deterioration, and high mortality.\n                    <jats:italic>Aeromonas hydrophila<\/jats:italic>\n                    is an important causative agent of NSTIs, but the bacterial mechanisms that promote tissue destruction,\n                    <jats:italic>in vivo<\/jats:italic>\n                    expansion, dissemination, and host lethality remain incompletely understood. Here, we investigated the contribution of the GspCD-dependent type II secretion system (T2SS) to\n                    <jats:italic>A. hydrophila<\/jats:italic>\n                    virulence using transposon mutants, extracellular protein analyses, and a mouse NSTI model. Mutants carrying transposon insertions in\n                    <jats:italic>gspD<\/jats:italic>\n                    and\n                    <jats:italic>gspC<\/jats:italic>\n                    showed defective secretion of a FLAG-tagged truncated AerA construct and markedly reduced hemolytic activity in culture supernatants. Comparative analysis of extracellular proteins further showed that disruption of\n                    <jats:italic>gspC<\/jats:italic>\n                    reduced the abundance of multiple known or predicted virulence-associated extracellular factors, including AerA, Ahh, lipase, and metalloprotease. In the mouse NSTI model, both mutants exhibited attenuated virulence, including reduced serum markers of tissue injury, less severe histopathological damage, impaired\n                    <jats:italic>in vivo<\/jats:italic>\n                    expansion and dissemination, and decreased lethality. Together, these findings show that the GspCD-dependent T2SS plays an important role in\n                    <jats:italic>A. hydrophila<\/jats:italic>\n                    NSTI pathogenesis by promoting extracellular protein secretion, tissue destruction, bacterial spread, and host mortality.\n                  <\/jats:p>","DOI":"10.3389\/fcimb.2026.1870837","type":"journal-article","created":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T05:41:48Z","timestamp":1782798108000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["The GspCD-dependent type II secretion system promotes necrotizing soft tissue infection caused by Aeromonas hydrophila"],"prefix":"10.3389","volume":"16","author":[{"given":"Yuka","family":"Tonosaki","sequence":"first","affiliation":[{"name":"Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University","place":["Aomori, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kohei","family":"Yamazaki","sequence":"additional","affiliation":[{"name":"Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University","place":["Aomori, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shota","family":"Owada","sequence":"additional","affiliation":[{"name":"Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University","place":["Aomori, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kei","family":"Yamaguchi","sequence":"additional","affiliation":[{"name":"Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University","place":["Aomori, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takashige","family":"Kashimoto","sequence":"additional","affiliation":[{"name":"Laboratory of Veterinary Public Health, School of Veterinary Medicine, Kitasato University","place":["Aomori, Japan"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,6,30]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"168","DOI":"10.1016\/S0966-842X(00)01722-4","article-title":"Adventures of a pore-forming toxin at the target cell surface","volume":"8","author":"Abrami","year":"2000","journal-title":"Trends Microbiol."},{"key":"B2","doi-asserted-by":"publisher","first-page":"1967","DOI":"10.1128\/iai.68.6.3792a-3792a.2000","article-title":"Mutations in the extracellular protein secretion pathway genes (eps) interfere with rugose polysaccharide production and motility of Vibrio cholerae","volume":"68","author":"Ali","year":"2000","journal-title":"Infect. 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