{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T23:29:51Z","timestamp":1791070191417,"version":"4.1.0"},"reference-count":46,"publisher":"American Society for Microbiology","issue":"7","license":[{"start":{"date-parts":[[2010,4,1]],"date-time":"2010-04-01T00:00:00Z","timestamp":1270080000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["J Bacteriol"],"published-print":{"date-parts":[[2010,4]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n          <jats:p>\n            The Gram-negative type II secretion (T2S) system is a multiprotein complex mediating the release of virulence factors from a number of pathogens. While an understanding of the function of T2S components is emerging, little is known about what identifies substrates for export. To investigate T2S substrate recognition, we compared mutations affecting the secretion of two highly homologous substrates: heat-labile enterotoxin (LT) from enterotoxigenic\n            <jats:italic>Escherichia coli<\/jats:italic>\n            (ETEC) and cholera toxin (CT) from\n            <jats:italic>Vibrio cholerae<\/jats:italic>\n            . Each toxin consists of one enzymatic A subunit and a ring of five B subunits mediating the toxin's secretion. Here, we report two mutations in LT's B subunit (LTB) that reduce its secretion from ETEC without global effects on the toxin. The Q3K mutation reduced levels of secreted LT by half, and as with CT (T. D. Connell, D. J. Metzger, M. Wang, M. G. Jobling, and R. K. Holmes, Infect. Immun. 63:4091-4098, 1995), the E11K mutation impaired LT secretion. Results\n            <jats:italic>in vitro<\/jats:italic>\n            and\n            <jats:italic>in vivo<\/jats:italic>\n            show that these mutants are not degraded more readily than wild-type LT. The Q3K mutation did not significantly affect CT B subunit (CTB) secretion from\n            <jats:italic>V. cholerae<\/jats:italic>\n            , and the E11A mutation altered LT and CTB secretion to various extents, indicating that these toxins are identified as secretion substrates in different ways. The levels of mutant LTB expressed in\n            <jats:italic>V. cholerae<\/jats:italic>\n            were low or undetectable, but each CTB mutant expressed and secreted at wild-type levels in ETEC. Therefore, ETEC's T2S system seems to accommodate mutations in CTB that impair the secretion of LTB. Our results highlight the exquisitely fine-tuned relationship between T2S substrates and their coordinate secretion machineries in different bacterial species.\n          <\/jats:p>","DOI":"10.1128\/jb.01542-09","type":"journal-article","created":{"date-parts":[[2010,1,23]],"date-time":"2010-01-23T03:03:24Z","timestamp":1264215804000},"page":"1902-1911","update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":22,"title":["Specificity of the Type II Secretion Systems of Enterotoxigenic\n            <i>Escherichia coli<\/i>\n            and\n            <i>Vibrio cholerae<\/i>\n            for Heat-Labile Enterotoxin and Cholera Toxin"],"prefix":"10.1128","volume":"192","author":[{"given":"Benjamin","family":"Mudrak","sequence":"first","affiliation":[{"name":"Departments of Molecular Genetics and Microbiology"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meta J.","family":"Kuehn","sequence":"additional","affiliation":[{"name":"Departments of Molecular Genetics and Microbiology"},{"name":"Biochemistry, Duke University Medical Center, Durham, North Carolina 27710"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","reference":[{"key":"e_1_3_2_2_2","doi-asserted-by":"publisher","DOI":"10.1128\/IAI.74.2.869-875.2006"},{"key":"e_1_3_2_3_2","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1006\/jmbi.2001.4594","volume":"308","year":"2001","unstructured":"Bouley, J., G. Condemine, and V. E. Shevchik. 2001. The PDZ domain of OutC and the N-terminal region of OutD determine the secretion specificity of the type II out pathway of Erwinia chrysanthemi. J. Mol. Biol. 308 : 205-219.","journal-title":"J. Mol. Biol."},{"key":"e_1_3_2_4_2","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1006\/jmbi.2000.4103","volume":"303","year":"2000","unstructured":"Chapon, V., H. D. Simpson, X. Morelli, E. Brun, and F. Barras. 2000. Alteration of a single tryptophan residue of the cellulose-binding domain blocks secretion of the Erwinia chrysanthemi Cel5 cellulase (ex-EGZ) via the type II system. J. Mol. Biol. 303 : 117-123.","journal-title":"J. Mol. Biol."},{"key":"e_1_3_2_5_2","doi-asserted-by":"crossref","first-page":"39465","DOI":"10.1074\/jbc.M606038200","volume":"281","year":"2006","unstructured":"Chung, W. Y., R. Carter, T. Hardy, M. Sack, T. R. Hirst, and R. F. James. 2006. Inhibition of Escherichia coli heat-labile enterotoxin B subunit pentamer (EtxB5) assembly in vitro using monoclonal antibodies. J. Biol. Chem. 281 : 39465-39470.","journal-title":"J. Biol. Chem."},{"key":"e_1_3_2_6_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.tim.2005.09.005"},{"key":"e_1_3_2_7_2","doi-asserted-by":"publisher","DOI":"10.1128\/iai.63.10.4091-4098.1995"},{"key":"e_1_3_2_8_2","doi-asserted-by":"crossref","first-page":"15065","DOI":"10.1016\/S0021-9258(18)33394-5","volume":"257","year":"1982","unstructured":"Copeland, B. R., R. J. Richter, and C. E. Furlong. 1982. Renaturation and identification of periplasmic proteins in two-dimensional gels of Escherichia coli. J. Biol. Chem. 257 : 15065-15071.","journal-title":"J. Biol. Chem."},{"key":"e_1_3_2_9_2","doi-asserted-by":"crossref","first-page":"1516","DOI":"10.1111\/j.1462-5822.2006.00736.x","volume":"8","year":"2006","unstructured":"Dorsey, F. C., J. F. Fischer, and J. M. Fleckenstein. 2006. Directed delivery of heat-labile enterotoxin by enterotoxigenic Escherichia coli. Cell. Microbiol. 8 : 1516-1527.","journal-title":"Cell. Microbiol."},{"key":"e_1_3_2_10_2","doi-asserted-by":"publisher","DOI":"10.1128\/jb.167.1.66-72.1986"},{"key":"e_1_3_2_11_2","doi-asserted-by":"publisher","DOI":"10.1128\/IAI.69.10.6310-6317.2001"},{"key":"e_1_3_2_12_2","doi-asserted-by":"publisher","DOI":"10.1128\/jb.165.3.715-722.1986"},{"key":"e_1_3_2_13_2","doi-asserted-by":"publisher","DOI":"10.1128\/jb.158.3.1115-1121.1984"},{"key":"e_1_3_2_14_2","doi-asserted-by":"crossref","first-page":"7109","DOI":"10.1073\/pnas.85.19.7109","volume":"85","year":"1988","unstructured":"Hardy, S. J., J. Holmgren, S. Johansson, J. Sanchez, and T. R. Hirst. 1988. Coordinated assembly of multisubunit proteins: oligomerization of bacterial enterotoxins in vivo and in vitro. Proc. Natl. Acad. Sci. U. S. A. 85 : 7109-7113.","journal-title":"Proc. Natl. Acad. Sci. U. S. A."},{"key":"e_1_3_2_15_2","first-page":"352","volume":"8","year":"2000","unstructured":"Henderson, I. R., J. P. Nataro, J. B. Kaper, T. F. Meyer, S. K. Farrand, D. L. Burns, B. B. Finlay, and J. W. St. Geme III. 2000. Renaming protein secretion in the gram-negative bacteria. Trends Microbiol. 8 : 352.","journal-title":"Trends Microbiol."},{"key":"e_1_3_2_16_2","doi-asserted-by":"crossref","first-page":"7752","DOI":"10.1073\/pnas.81.24.7752","volume":"81","year":"1984","unstructured":"Hirst, T. R., J. Sanchez, J. B. Kaper, S. J. Hardy, and J. Holmgren. 1984. Mechanism of toxin secretion by Vibrio cholerae investigated in strains harboring plasmids that encode heat-labile enterotoxins of Escherichia coli. Proc. Natl. Acad. Sci. U. S. A. 81 : 7752-7756.","journal-title":"Proc. Natl. Acad. Sci. U. S. A."},{"key":"e_1_3_2_17_2","doi-asserted-by":"crossref","first-page":"754","DOI":"10.1016\/j.jmb.2007.05.064","volume":"371","year":"2007","unstructured":"Holmner, A., G. Askarieh, M. Okvist, and U. Krengel. 2007. Blood group antigen recognition by Escherichia coli heat-labile enterotoxin. J. Mol. Biol. 371 : 754-764.","journal-title":"J. Mol. Biol."},{"key":"e_1_3_2_18_2","doi-asserted-by":"crossref","first-page":"8070","DOI":"10.1074\/jbc.M308633200","volume":"279","year":"2004","unstructured":"Horstman, A. L., S. J. Bauman, and M. J. Kuehn. 2004. Lipopolysaccharide 3-deoxy-d-manno-octulosonic acid (Kdo) core determines bacterial association of secreted toxins. J. Biol. Chem. 279 : 8070-8075.","journal-title":"J. Biol. Chem."},{"key":"e_1_3_2_19_2","doi-asserted-by":"crossref","first-page":"32538","DOI":"10.1074\/jbc.M203740200","volume":"277","year":"2002","unstructured":"Horstman, A. L., and M. J. Kuehn. 2002. Bacterial surface association of heat-labile enterotoxin through lipopolysaccharide after secretion via the general secretory pathway. J. Biol. Chem. 277 : 32538-32545.","journal-title":"J. Biol. Chem."},{"key":"e_1_3_2_20_2","doi-asserted-by":"crossref","first-page":"12489","DOI":"10.1074\/jbc.275.17.12489","volume":"275","year":"2000","unstructured":"Horstman, A. L., and M. J. Kuehn. 2000. Enterotoxigenic Escherichia coli secretes active heat-labile enterotoxin via outer membrane vesicles. J. Biol. Chem. 275 : 12489-12496.","journal-title":"J. Biol. Chem."},{"key":"e_1_3_2_21_2","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1006\/plas.1997.1309","volume":"38","year":"1997","unstructured":"Jobling, M. G., L. M. Palmer, J. L. Erbe, and R. K. Holmes. 1997. Construction and characterization of versatile cloning vectors for efficient delivery of native foreign proteins to the periplasm of Escherichia coli. Plasmid 38 : 158-173.","journal-title":"Plasmid"},{"key":"e_1_3_2_22_2","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1111\/j.1574-6968.2006.00102.x","volume":"255","year":"2006","unstructured":"Johnson, T. L., J. Abendroth, W. G. Hol, and M. Sandkvist. 2006. Type II secretion: from structure to function. FEMS Microbiol. Lett. 255 : 175-186.","journal-title":"FEMS Microbiol. Lett."},{"key":"e_1_3_2_23_2","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1046\/j.1365-2958.1998.00679.x","volume":"27","year":"1998","unstructured":"Kagami, Y., M. Ratliff, M. Surber, A. Martinez, and D. N. Nunn. 1998. Type II protein secretion by Pseudomonas aeruginosa: genetic suppression of a conditional mutation in the pilin-like component XcpT by the cytoplasmic component XcpR. Mol. Microbiol. 27 : 221-233.","journal-title":"Mol. Microbiol."},{"key":"e_1_3_2_24_2","doi-asserted-by":"crossref","first-page":"515","DOI":"10.1007\/BF00290577","volume":"249","year":"1995","unstructured":"McVay, C. S., and A. N. Hamood. 1995. Toxin A secretion in Pseudomonas aeruginosa: the role of the first 30 amino acids of the mature toxin. Mol. Gen. Genet. 249 : 515-525.","journal-title":"Mol. Gen. Genet."},{"key":"e_1_3_2_25_2","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/0092-8674(83)90228-3","volume":"35","year":"1983","unstructured":"Mekalanos, J. J. 1983. Duplication and amplification of toxin genes in Vibrio cholerae. Cell 35 : 253-263.","journal-title":"Cell"},{"key":"e_1_3_2_26_2","doi-asserted-by":"crossref","first-page":"745","DOI":"10.1111\/j.1365-2958.1994.tb00467.x","volume":"13","year":"1994","unstructured":"Merritt, E. A., T. K. Sixma, K. H. Kalk, B. A. van Zanten, and W. G. Hol. 1994. Galactose-binding site in Escherichia coli heat-labile enterotoxin (LT) and cholera toxin (CT). Mol. Microbiol. 13 : 745-753.","journal-title":"Mol. Microbiol."},{"key":"e_1_3_2_27_2","doi-asserted-by":"publisher","DOI":"10.1128\/JB.01622-08"},{"key":"e_1_3_2_28_2","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1126\/science.6857285","volume":"221","year":"1983","unstructured":"Neill, R. J., B. E. Ivins, and R. K. Holmes. 1983. Synthesis and secretion of the plasmid-coded heat-labile enterotoxin of Escherichia coli in Vibrio cholerae. Science 221 : 289-291.","journal-title":"Science"},{"key":"e_1_3_2_29_2","doi-asserted-by":"crossref","first-page":"585","DOI":"10.1046\/j.1365-2958.2002.02793.x","volume":"43","year":"2002","unstructured":"Palomaki, T., R. Pickersgill, R. Riekki, M. Romantschuk, and H. T. Saarilahti. 2002. A putative three-dimensional targeting motif of polygalacturonase (PehA), a protein secreted through the type II (GSP) pathway in Erwinia carotovora. Mol. Microbiol. 43 : 585-596.","journal-title":"Mol. Microbiol."},{"key":"e_1_3_2_30_2","doi-asserted-by":"publisher","DOI":"10.1128\/iai.50.3.813-816.1985"},{"key":"e_1_3_2_31_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.mib.2008.11.010"},{"key":"e_1_3_2_32_2","doi-asserted-by":"crossref","first-page":"19118","DOI":"10.1074\/jbc.271.32.19118","volume":"271","year":"1996","unstructured":"Ruddock, L. W., J. J. Coen, C. Cheesman, R. B. Freedman, and T. R. Hirst. 1996. Assembly of the B subunit pentamer of Escherichia coli heat-labile enterotoxin. Kinetics and molecular basis of rate-limiting steps in vitro. J. Biol. Chem. 271 : 19118-19123.","journal-title":"J. Biol. Chem."},{"key":"e_1_3_2_33_2","doi-asserted-by":"publisher","DOI":"10.1006\/jmbi.1998.1791"},{"key":"e_1_3_2_34_2","doi-asserted-by":"crossref","first-page":"388","DOI":"10.1016\/j.coi.2005.06.007","volume":"17","year":"2005","unstructured":"Sanchez, J., and J. Holmgren. 2005. Virulence factors, pathogenesis and vaccine protection in cholera and ETEC diarrhea. Curr. Opin. Immunol. 17 : 388-398.","journal-title":"Curr. Opin. Immunol."},{"key":"e_1_3_2_35_2","doi-asserted-by":"publisher","DOI":"10.1128\/jb.179.22.6994-7003.1997"},{"key":"e_1_3_2_36_2","doi-asserted-by":"crossref","first-page":"13978","DOI":"10.1073\/pnas.241411198","volume":"98","year":"2001","unstructured":"Scott, M. E., Z. Y. Dossani, and M. Sandkvist. 2001. Directed polar secretion of protease from single cells of Vibrio cholerae via the type II secretion pathway. Proc. Natl. Acad. Sci. U. S. A. 98 : 13978-13983.","journal-title":"Proc. Natl. Acad. Sci. U. S. A."},{"key":"e_1_3_2_37_2","doi-asserted-by":"publisher","DOI":"10.1128\/JB.00514-08"},{"key":"e_1_3_2_38_2","doi-asserted-by":"publisher","DOI":"10.1128\/JB.00583-07"},{"key":"e_1_3_2_39_2","doi-asserted-by":"publisher","DOI":"10.1128\/mr.56.4.622-647.1992"},{"key":"e_1_3_2_40_2","doi-asserted-by":"publisher","DOI":"10.1128\/JB.01531-08"},{"key":"e_1_3_2_41_2","doi-asserted-by":"crossref","first-page":"7066","DOI":"10.1073\/pnas.092152899","volume":"99","year":"2002","unstructured":"Tauschek, M., R. J. Gorrell, R. A. Strugnell, and R. M. Robins-Browne. 2002. Identification of a protein secretory pathway for the secretion of heat-labile enterotoxin by an enterotoxigenic strain of Escherichia coli. Proc. Natl. Acad. Sci. U. S. A. 99 : 7066-7071.","journal-title":"Proc. Natl. Acad. Sci. U. S. A."},{"key":"e_1_3_2_42_2","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1007\/BF00731304","volume":"11","year":"1994","unstructured":"Teneberg, S., T. R. Hirst, J. Angstrom, and K. A. Karlsson. 1994. Comparison of the glycolipid-binding specificities of cholera toxin and porcine Escherichia coli heat-labile enterotoxin: identification of a receptor-active non-ganglioside glycolipid for the heat-labile toxin in infant rabbit small intestine. Glycoconj. J. 11 : 533-540.","journal-title":"Glycoconj. J."},{"key":"e_1_3_2_43_2","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1016\/S0378-1119(02)01151-4","volume":"303","year":"2003","unstructured":"Teo, J. W., L. H. Zhang, and C. L. Poh. 2003. Cloning and characterization of a metalloprotease from Vibrio harveyi strain AP6. Gene 303 : 147-156.","journal-title":"Gene"},{"key":"e_1_3_2_44_2","doi-asserted-by":"crossref","first-page":"8552","DOI":"10.1016\/S0021-9258(17)39508-X","volume":"260","year":"1985","unstructured":"Tsuji, T., T. Honda, T. Miwatani, S. Wakabayashi, and H. Matsubara. 1985. Analysis of receptor-binding site in Escherichia coli enterotoxin. J. Biol. Chem. 260 : 8552-8558.","journal-title":"J. Biol. Chem."},{"key":"e_1_3_2_45_2","doi-asserted-by":"crossref","first-page":"14451","DOI":"10.1016\/S0021-9258(18)98707-7","volume":"266","year":"1991","unstructured":"Wong, K. R., and J. T. Buckley. 1991. Site-directed mutagenesis of a single tryptophan near the middle of the channel-forming toxin aerolysin inhibits its transfer across the outer membrane of Aeromonas salmonicida. J. Biol. Chem. 266 : 14451-14456.","journal-title":"J. Biol. Chem."},{"key":"e_1_3_2_46_2","doi-asserted-by":"publisher","DOI":"10.1128\/jb.169.3.1352-1357.1987"},{"key":"e_1_3_2_47_2","doi-asserted-by":"publisher","DOI":"10.1128\/JB.00224-08"}],"container-title":["Journal of Bacteriology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/JB.01542-09","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/JB.01542-09","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,7,29]],"date-time":"2021-07-29T17:16:33Z","timestamp":1627578993000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/JB.01542-09"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,4]]},"references-count":46,"journal-issue":{"issue":"7","published-print":{"date-parts":[[2010,4]]}},"alternative-id":["10.1128\/JB.01542-09"],"URL":"https:\/\/doi.org\/10.1128\/jb.01542-09","relation":{},"ISSN":["0021-9193","1098-5530"],"issn-type":[{"value":"0021-9193","type":"print"},{"value":"1098-5530","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,4]]},"assertion":[{"value":"2009-11-25","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2010-01-13","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2020-12-20","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}