title: Identification of novel semenogelin I-derived antimicrobial peptide from liquefied human seminal plasma.
abstract: Semenogelin I (SgI) is one of the most abundant proteins in human seminal plasma. SgI plays a key role in sperm coagulation and spermatozoon immobilization. In addition, SgI and/or its proteolytic fragments are involved in regulating spermatozoon motility, capacitation and inhibin-like activity. However, little is known about the antibacterial activity of SgI-derived peptides. By a combination of ion-exchange, gel filtration and high-performance liquid chromatography, peptides from liquefied human seminal plasma from 40 healthy donors were isolated and characterized. N-terminal amino-acid sequencing and fast atom bombardment mass spectrometry revealed that four isolated peptides were SgI-derived, namely SgI-29 (85-113), SgI-46 (85-130), SgI-47 (85-131) and SgI-52 (85-136). Interestingly, SgI-29, SgI-46 and SgI-47 are newly identified SgI-derived peptides. Antimicrobial activity assay results indicated that synthesized SgI-29 had strong antibacterial activity toward various bacterial strains. Our results indicate that SgI can be digested into small fragments like newly identified SgI-29, SgI-46 and SgI-47 and may have diversified functions.
authors.affiliation: Department of Urology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhao
authors.forename: Wen-Hui
authors.initials: WH
authors.lastname: Lee
authors.forename: Ji-Hong
authors.initials: JH
authors.lastname: Shen
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D012661:Semen / Q000737:chemistry; D029607:Seminal Vesicle Secretory Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D010446:Peptide Fragments; D029607:Seminal Vesicle Secretory Proteins; C424482:seminal vesicle-specific antigen