title: Expression of extracellular superoxide dismutase in the human male reproductive tract, detected using antisera raised against a recombinant protein.
abstract: Mammalian spermatozoa are particularly susceptible to the deleterious effects of reactive oxygen species and lipid peroxidation, which ultimately lead to impaired fertility. A number of enzymes are present in the male reproductive tract which may play a role in preventing oxidative damage; in particular, the epididymis is the site of synthesis and secretion of large amounts of extracellular superoxide dismutase (eSOD). In order to study the distribution of eSOD in the male reproductive tract, and distinguish it from other related superoxide dismutase isoenzymes (e.g. cytosolic SOD), polyclonal antisera have been raised against a recombinant human eSOD fusion protein, expressed in bacterial cells. This protein was expressed from a synthetic gene fragment, using preferred Escherichia coli codons, designed to overcome the problems associated with the high guanine+cytosine content of the natural human eSOD transcript. Using this antiserum, eSOD can be readily detected in a range of human reproductive tissues as well as in human seminal plasma. However, the presence of similar levels of eSOD in the seminal plasma of vasectomized men (probably of prostatic origin) precludes its use as a simple diagnostic indicator of eSOD activity levels in the epididymis.
authors.affiliation: Department of Biochemistry, University of Bristol, School of Medical Sciences, UK.
authors.forename: K
authors.initials: K
authors.lastname: Williams
authors.forename: J
authors.initials: J
authors.lastname: Frayne
authors.forename: E A
authors.initials: EA
authors.lastname: McLaughlin
authors.forename: L
authors.initials: L
authors.lastname: Hall
mesh_terms: D000595:Amino Acid Sequence; D001482:Base Composition; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular / Q000379:methods; D004247:DNA / Q000737:chemistry; D019281:Dimerization; D004926:Escherichia coli / Q000235:genetics; D005813:Genes, Synthetic / Q000235:genetics; D006801:Humans; D007106:Immune Sera; D007527:Isoenzymes / Q000032:analysis* / Q000737:chemistry / Q000235:genetics; D008297:Male; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010920:Placenta / Q000201:enzymology; D011467:Prostate / Q000201:enzymology; D011993:Recombinant Fusion Proteins; D012661:Semen / Q000201:enzymology*; D013482:Superoxide Dismutase / Q000032:analysis* / Q000737:chemistry / Q000235:genetics; D013737:Testis / Q000201:enzymology*; D014599:Uterus / Q000201:enzymology
chemical_list: D007106:Immune Sera; D007527:Isoenzymes; D011993:Recombinant Fusion Proteins; D004247:DNA; D013482:Superoxide Dismutase