The interaction between the gelatin-binding domain of fibronectin and the attachment of Pasteuria penetrans endospores to nematode cuticle

Pasteuria Penetrans is a Gram-positive endospore-producing bacterium that i s a parasite of root-knot nematodes. Attachment of endospores to the cuticl e of the nematode is the first stage in the infection process. Western blot analysis with monoclonal and polyclonal antibodies that recognize the 30 k Da heparin-binding domain (HBD) and the 45 kDa gelatin-binding domain (GBD) fragments of human fibronectin (Fn) revealed a series of polypeptides of a pproximately 40, 45 and 55 kDa present in crude cuticle extracts of Meloido gyne javanica 2nd-stage juveniles. The results suggest that the structure o f the nematode fibronectin is different to the fibronectins so far characte rized. Pre-treatment of endospores of Pasteuria with either the HBD or the GBD was found to inhibit binding to the nematode cuticle. The larger GBD fr agment was the most effective at blocking adhesion. Pre-treatment of the GB D fragment with gelatin prevented the GBD fragment from inhibiting endospor e attachment to the nematode cuticle.