ANTIBODIES FROM CHICKEN EGGS AS PROBES FOR ANTIGENS FROM PASTEURIA-PENETRANS ENDOSPORES

The bacteria Pasteuria spp. have been identified as among the most pro mising of several microbial organisms currently under investigation as biological control agents of plant-parasitic nematodes. As part of ou r goal to develop methods to discriminate isolates of Pasteuria penetr ans with different host preferences, we investigated the potential of developing antibody probes to identify endospores of different isolate s of P. penetrans. Polyclonal IgY antibodies were raised in chickens a gainst endospores of P. penetrans isolates P20 and P100. Hens were inj ected with P20 or P100 endospore suspensions and boosted at 14 days. A nti-spore titers were determined with ELISA on yolk estracts of indivi dual eggs as a function of time. The highest titers were found in eggs produced at 22 to 35 days after initial injections. Yolk extracts she lving the highest titers were combined and processed to provide partia lly purified IgY preparations. SDS-PAGE and immunoblot analyses identi fied protein antigens with M-r values of 23-24, 46, and 57-59 KDa comm on to both P20 and P100 endospores. One protein antigen with an M-r va lue of 62 KDa was unique to the P100 endospores. The IgY antibodies re duced the attachment of Pasteuria endospores to their nematode hosts, indicating antibody interaction with antigens on the endospore surface that are involved in the recognition and attachment processes.