Identification of the region that plays an important role in determining antibacterial activity of bovine seminalplasmin

Abstract

Seminalplasmin (SPLN) is a 47-residue protein isolated from bovine seminal plasma having potent antimicrobial activity against a broad spectrum of microorganisms. SPLN, also known as caltrin, acts as a calcium transport regulator in bovine sperms. Analysis of the sequence of SPLN reveals a 27-residue stretch with the sequence SLSRYAKLANRLANPKL-LETFLSKWIG more hydrophobic than the rest of the protein. It is demonstrated that a synthetic peptide corresponding to this 27-residue segment has antimicrobial activity comparable to that of SPLN. It does not exhibit hemolytic activity at concentrations where antibacterial activity is observed. Since P27 can be conveniently obtained in large amounts by chemical synthesis, it could serve not only as a starting compound to obtain peptides with improved antibacterial activity but also to understand the role of SPLN in reproductive physiology.

Immunohistochemical Localization of Protein Gene Product 9.5, Ubiquitin, and Neuropeptide Y Immunoreactivities in Epithelial and Neuroendocrine Cells from Normal and Hyperplastic Human Prostate

“…This peptide has a role in calcium transport regulation in sperm and in modulation of the zona pellucida-induced acrosome reaction (Herzog et al 1995). Interestingly, NPY also appears to have remarkable antibacterial activity, which could be important in maintaining a germ-free environment during fertilization (Sitaram et al 1997). The observation of NPY immunoreactivity in epithelial prostate cells and their secretions is also in agreement with the detection of NPY in prostasomes (prostate-derived organelles present in human seminal plasma) (Stridsberg et al 1996;Arienti et al 1998).…”

A novel synthetic peptide derivative from lactoferrin exhibiting antimicrobial activity

“…The mechanism of the tetrapeptide action is confirmed by the increase in β‐galactosidase activity in E. coli cells treated with different concentrations of the tetrapeptide derivatives. A similar increase in β‐galactosidase activity has been reported in E. coli cells treated with the seminalplasmin‐related peptide P27 [16]. Since the problem of antibiotic resistance is presently a severe one, peptides might prove useful in combating bacterial infection.…”

Seminal Plasma: An Essential Attribute to Spermatozoa

“…The biosynthesis of seminalplasmin occurs in seminal vesicles of bulls (Wempe et al, 1990). SPLN, also known as caltrin, acts as a calcium transport regulator on bull spermatozoa (Sitaram et al, 1997) and its presence on PM has been proposed to be essential for bringing about the physiologically relevant zona pellucida agonist‐induced acrosomal reaction in bull spermatozoa (Clark et al, 1993). SPLN is shown to be a potent inhibitor of reverse transcriptases RNA‐dependent DNA nucleotydyltransferases (Reddy et al, 1983), and it possesses antimicrobial property by inhibiting the growth, as well as nucleic acid and protein synthesis, of several bacteria (Scheit et al, 1985) and by increasing bacterial membrane permeability (Sitaram et al, 1992).…”