{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:11:25Z","timestamp":1787026285231,"version":"build-2736575974"},"reference-count":55,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,4,29]],"date-time":"2021-04-29T00:00:00Z","timestamp":1619654400000},"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                    Bacterial Type III Secretion Systems (T3SSs) are specialized multicomponent nanomachines that mediate the transport of proteins either to extracellular locations or deliver Type III Secretion effectors directly into eukaryotic host cell cytoplasm.\n                    <jats:italic>Shigella<\/jats:italic>\n                    , the causing agent of bacillary dysentery or shigellosis, bears a set of T3SS proteins termed translocators that form a pore in the host cell membrane. IpaB, the major translocator of the system, is a key factor in promoting\n                    <jats:italic>Shigella<\/jats:italic>\n                    pathogenicity. Prior to secretion, IpaB is maintained inside the bacterial cytoplasm in a secretion competent folding state thanks to its cognate chaperone IpgC. IpgC couples T3SS activation to transcription of effector genes through its binding to MxiE, probably after the delivery of IpaB to the secretion export gate. Small Angle X-ray Scattering experiments and modeling reveal that IpgC is found in different oligomeric states in solution, as it forms a stable heterodimer with full-length IpaB in contrast to an aggregation-prone homodimer in the absence of the translocator. These results support a stoichiometry of interaction 1:1 in the IpgC\/IpaB complex and the multi-functional nature of IpgC under different T3SS states.\n                  <\/jats:p>","DOI":"10.3389\/fcimb.2021.673122","type":"journal-article","created":{"date-parts":[[2021,4,29]],"date-time":"2021-04-29T08:05:06Z","timestamp":1619683506000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":11,"title":["Structural Insights of Shigella Translocator IpaB and Its Chaperone IpgC in Solution"],"prefix":"10.3389","volume":"11","author":[{"given":"Mariana L.","family":"Ferrari","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Spyridoula N.","family":"Charova","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philippe J.","family":"Sansonetti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Efstratios","family":"Mylonas","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anastasia D.","family":"Gazi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,4,29]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"e1002983","DOI":"10.1371\/journal.pgen.1002983","article-title":"The Non-Flagellar Type III Secretion System Evolved From the Bacterial Flagellum and Diversified Into Host-Cell Adapted Systems","volume":"8","author":"Abby","year":"2012","journal-title":"PloS Genet."},{"key":"B2","doi-asserted-by":"publisher","first-page":"4062","DOI":"10.1021\/bi300243z","article-title":"Binding Affects the Tertiary and Quaternary Structures of the Shigella Translocator Protein IpaB and its Chaperone Ipgc","volume":"51","author":"Adam","year":"2012","journal-title":"Biochemistry"},{"key":"B3","doi-asserted-by":"publisher","first-page":"1","DOI":"10.3390\/microorganisms8121933","article-title":"The t3ss of Shigella: Expression, Structure, Function, and Role in Vacuole Escape","volume":"8","author":"Bajunaid","year":"2020","journal-title":"Microorganisms"},{"key":"B4","doi-asserted-by":"publisher","first-page":"395","DOI":"10.1016\/j.jmb.2012.01.026","article-title":"The Structures of Coiled-Coil Domains From Type III Secretion System Translocators Reveal Homology to Pore-Forming Toxins","volume":"417","author":"Barta","year":"2012","journal-title":"J. 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