{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T11:06:03Z","timestamp":1791025563144,"version":"4.1.0"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"2","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2003,6,1]]},"abstract":"<jats:p>During passage through the epididymis, sperm interact with secreted epididymal proteins that promote maturation, including the acquisition of motility and fertilization competence. Viewed previously as distinct from sperm maturation, host defence capabilities are now recognized functions of the human epididymis 2 (HE2) family of sperm-binding proteins. We analysed the potent dose and time-dependent bactericidal activity of recombinant HE2\u03b1, HE2\u03b21 and HE2\u03b22 and found that the full-length proteins (10 \u03bcg\/ml or ~1 \u03bcM) caused more than a 50% decrease in Escherichia coli colony forming units within 15 min. By contrast, human \u03b2-defensin-1, at a similar concentration, required more than 90 min to exhibit similar antibacterial activity. The epididymis-specific lipocalin, LCN6, failed to kill bacteria. Higher concentrations (25\u2013100 \u03bcg\/ml) of HE2 proteins and a longer duration of treatment resulted in near total inhibition of bacterial growth. The C-terminal peptides of HE2\u03b1, HE\u03b21 and HE\u03b22 proteins exhibited antibacterial activity similar to their full-length counterparts, indicating that the antibacterial activity of HE2 proteins resides in these C-terminal regions. Antibacterial activities of HE2 proteins and peptides were slightly inhibited by NaCl concentrations of up to 150 mM, while human \u03b2-defensin-1 activity was nearly eliminated. Reduction and alkylation of disulphide bonds in HE2 proteins and their C-terminal peptides abolished their antibacterial activity. Consistent with the ability to kill bacteria, full-length HE2 proteins and C-terminal peptides caused rapid dose-dependent permeabilization of outer and cytoplasmic E. coli membranes. A much longer exposure time was required for human \u03b2-defensin-1-mediated permeabilization of membranes, suggesting a possible difference in mode of action compared with the HE2 antibacterial peptides.<\/jats:p>","DOI":"10.1042\/bj20030225","type":"journal-article","created":{"date-parts":[[2003,6,9]],"date-time":"2003-06-09T11:39:13Z","timestamp":1055158753000},"page":"473-483","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":69,"title":["Antibacterial properties of the sperm-binding proteins and peptides of human epididymis 2 (HE2) family; salt sensitivity, structural dependence and their interaction with outer and cytoplasmic membranes of Escherichia coli"],"prefix":"10.1042","volume":"372","author":[{"given":"Suresh","family":"YENUGU","sequence":"first","affiliation":[{"name":"Laboratories for Reproductive Biology, Department of Pediatrics, University of North Carolina, Chapel Hill, NC 27599-7500, U.S.A."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katherine G.","family":"HAMIL","sequence":"additional","affiliation":[{"name":"Laboratories for Reproductive Biology, Department of Pediatrics, University of North Carolina, Chapel Hill, NC 27599-7500, U.S.A."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charles E.","family":"BIRSE","sequence":"additional","affiliation":[{"name":"Human Genome Sciences Inc., 9410 Key West Avenue, Rockville, MD 20850-3338, U.S.A."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Steven M.","family":"RUBEN","sequence":"additional","affiliation":[{"name":"Human Genome Sciences Inc., 9410 Key West Avenue, Rockville, MD 20850-3338, U.S.A."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frank S.","family":"FRENCH","sequence":"additional","affiliation":[{"name":"Laboratories for Reproductive Biology, Department of Pediatrics, University of North Carolina, Chapel Hill, NC 27599-7500, U.S.A."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susan H.","family":"HALL","sequence":"additional","affiliation":[{"name":"Laboratories for Reproductive Biology, Department of Pediatrics, University of North Carolina, Chapel Hill, NC 27599-7500, U.S.A."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/372\/2\/473\/737588\/bj3720473.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/372\/2\/473\/737588\/bj3720473.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,22]],"date-time":"2021-11-22T12:42:54Z","timestamp":1637584974000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/372\/2\/473\/40901\/Antibacterial-properties-of-the-sperm-binding"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2003,6,1]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2003,6,1]]}},"URL":"https:\/\/doi.org\/10.1042\/bj20030225","relation":{},"ISSN":["0264-6021","1470-8728"],"issn-type":[{"value":"0264-6021","type":"print"},{"value":"1470-8728","type":"electronic"}],"subject":[],"published":{"date-parts":[[2003,6,1]]}}}