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SLLP1, A Unique, Intra-Acrosomal, Non-Bacteriolytic, C Lysozyme-like Protein of Human Spermatozoa

NCJ Number
Biology of Reproduction Volume: 68 Issue: 5 Dated: 2003 Pages: 1525-1537
Date Published
13 pages

This study investigated the presence of a unique c lysozyme-like protein in human spermatozoa.


During research that included mining of a human two-dimensional gel sperm proteome, scientists discovered the presence of several novel proteins including a unique c lysozyme-like protein identified as SLLP1. C lysozymes (chicken-type lysozymes) are N-acetylglucosamine-binding proteins that have not yet been identified as being present in human sperm. These proteins are important as they could play a possible role in sperm/egg adhesion during fertilization. This article describes the extraction and separation of sperm proteins from samples of human semen that tested negative by serology for HIV. The proteins were microsequenced and cloned, and a number of different analyses were conducted on the separated proteins. The study found that when antisera to SPPL1 were introduced, it blocked binding in the hamster egg penetration assay. This finding suggests that SPPL1 may have a role to play in binding the sperm to the egg during fertilization however; the specifics of this role will need to be examined in additional research. Tables, figures, and references

Date Published: January 1, 2003