In Vivo Binding of the Salivary Glycoprotein EP-GP (Identical to GCDFP-15) to Oral and Non-Oral Bacteria Detection and Identification of EP-GP Binding Species

Abstract

Extra Parotid Glycoprotein (EP-GP) is a glycoprotein isolated from human saliva, having homologues in several other body fluids. The biological role of EP-GP and its homologues is unknown. Recently, EP-GP was shown to bind in vitro to the bacterium Streptococcus salivarius HB. In contrast, no binding to a number of other oral microorganisms could be demonstrated. In the present study we have determined whether binding of EP-GP to bacteria occurs in vivo in saliva and in other EP-GP containing body fluids. Therefore the presence of EP-GP on bacteria in vivo was determined by analyzing oral, skin and ear floras by confocal fluoresence microscopy using specific antibodies. About 12% of the in vivo oral flora had EP-GP present on their surface, while approximately 5% of the bacteria from ear canal or skin was positive for EP-GP. IgA was detected on approximately 65% of the salivary bacteria, whereas the high-molecular weight mucin (MG1) and cystatin C were not detectable on any oral bacterium. Using a replica-plate assay, a number of EP-GP binding strains in saliva were isolated and identified as Gemella haemolysans, Gemella morbillorium, Streptococcus acidominimus, Streptococcus oralis, Streptococcus salivarius and Streptococcus parasanguis. Bacteria from the ear canal and skin bacteria were identified as Staphylococcus hominis. It is concluded that EP-GP is selectively bound in vivo to several oral and non-oral bacterial species.

Proteomic Analysis of a 14.2 kDa Protein Isolated from Bali Cattle(Bos Sondaicus/Javanicus)Saliva Using Single Dimension Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis and Matrix-Assisted Laser Desorption Ionization Time-of-Flight Tandem Mass Spectrometer

“…Furthermore, observation of the bactericidal activity of the 14.2 kDa proteins (Depamede et al, 2012) also strengthens the similarity of these proteins with PIP, since PIP was reported to have affinity to Staphylococcus mutant in human saliva (Ambatipudi et al, 2010). Furthermore, Schenkels et al (1997) also reported that PIP might modulate the colonisation of oral and non-oral bacteria such as those of the genera Streptococcus as well as Gemella, and Staphylococcus hominis isolated from human skin and ear canal. Since the three proteins were observed in Bos taurus as well as in other mammals such as rats, mice, and ovine, it would be interesting to check whether proteins can be used for evolution studies on Bali cattle (Bos sondaicus/javanicus) and ruminants in general.…”

Prolactin inducible protein in cancer, fertility and immunoregulation: structure, function and its clinical implications

“…Its predominance in mucosaltype tissues, as well as its presence in saliva, tears, submucosal glands of the bronchi and apocrine glands of the skin, suggests that PIP may play an important role in mucosal immunity [24]. Schenkels et al [14] used the replica-plate assay to determine the binding of PIP with several bacterial strains in saliva, specifically, Gemella haemolysans, Gemella morbillorium, Streptococcus acidominimus, Streptococcus oralis, Streptococcus salivarius and Streptococcus parasanguis. Similarly, bacteria from the ear canal and skin were identified as Staphylococcus hominis.…”

“…Moreover, it was postulated that since PIP is capable to bind with hydroxyapatite (a major component of tooth enamel), it may participate in formation of the enamel pellicle [88]. It appears that PIP modulates bacterial colonization because it binds to oral bacteria such as Streptococcus and Gemella [14]. Apart from human, PIP has also been identified and purified in rat saliva [24].…”

“…Finally, it was designated as a sensitive and specific marker for monitoring and defining apocrine differentiation in breast cancer [13]. PIP also binds to enamel pellicle of teeth and oral bacteria and it was suggested that PIP may be involved in modulating the colonization of bacteria in many oral and other biological fluids [14]. Lopez-Ottin and Diamandis [15] have reviewed five common proteins present in breast and prostate cancers and found that PIP is among them and it shares every common feature [13,16].…”

Antimicrobial Peptides in Saliva and Salivary Glands: Their Roles in the Oral Defense System

“…OBP II in the rat shows a 45.5% amino acid identity in a 178 aminoacid overlap with the VEG protein (62). Schenkels et al (63) reported the biochemical characteristics of human lipocalin VEG protein and of extra parotid glycoprotein (EP-GP) isolated with hydroxyapatite-binding assay from the SM and SL glands. EP-GP protein is distributed widely in human tissues in various forms in saliva, sweat, tears, nasal mucus, and seminal fluid.…”