SUMMARY: Conidia of the endoparasitic nematophagous fungus Drechmeria coniospora adhere to the sensory organs of many nematode species. In some cases the adhesion phase is followed by penetration of the nematode cuticle and subsequent infection. In a study of eight different nematode species and five strains of the fungus only two species were infected: Panagrellus redivivus was infected by all strains and Ditylenchus dipsaci was infected by four strains, although the conidia of all fungal strains adhered to all of the nematode species tested. Treatment of the nematode P. redivivus and the conidia of D. coniospora with proteases gave a decreased adhesion in contrast to glycosidases, lipases and other enzymes tested. Inhibitory effects on adhesion were obtained after treatment of conidia with the carbohydrate N-acetylneuraminic acid; and the amino acids alanine and proline. Hydrophobicity and electrical charge appear not to be involved in conidial adhesion. A previous hypothesis on the presence of a sialic-acid-specific lectin in this interaction appears to be incorrect and the present results indicate no involvement of carbohydrates in the adhesion process. The results suggest that the adhesion is mediated by protein(s) in the adhesive part of the conidium binding to protein(s) excreted from the sensory organs of the nematodes.
BacicA.,
KahaneI.,
ZuckermanB.M.1990; Panagrellus redivivus and Caenorhabditis elegans: evidence for the absence of sialic acids.. Experimental Parasitology 71:483–488
DijksterhuisJ.,
VeenhuisM.,
HarderW.1990; Ultrastructural study of the adhesion and initial stages of infection of nematodes by conidiospores of Drechmeria coniospora.
. Mycological Research 94:1–8
HazenK.C.,
HazenB.W.1987; A polystyrene microsphere assay for detecting surface hydrophobicity variations within Candida albicans populations.. Journal of Microbiological Methods 6:289–299
JanssonH.-B.,
Nordbring-HertzB.1983; The endoparasitic nematophagous fungus Meria coniospora infects nematodes specifically at the chemosensory organs.. Journal of General Microbiology 129:1121–1126
JanssonH.-B.,
Nordbring-HertzB.1984; Involvement of sialic acid in nematode chemotaxis and infection by an endoparasitic nematophagous fungus.. Journal of General Microbiology 130:39–43
JanssonH.-B.,
Nordbring-HertzB.1988; Infection events in the fungus-nematode system.. In Diseases of NematodesII pp 59–72PoinarG.O.JrJanssonH.-B.
Edited by Boca Raton: CRC Press.;
JanssonH.-B.,
Von HofstenA.,
Von MecklenburgC.1984; Life cycle of the endoparasitic fungusMeria coniospora: a light and electron microscopic study.. Antonie van Leeuwenhoek 50:312–327
JanssonH.-B.,
JeyaprakashA.,
ZuckermanB.M.1985; Differential adhesion and infection of nematodes by the endoparasitic fungusMeria coniospora (Deuteromycetes).. Applied and Environmental Microbiology 46:552–555
JanssonH.-B.,
DackmanC.,
ZuckermanB.M.1987; Adhesion and infection of plant parasitic nematodes by the fungusDrechmeria coniospora.
. Nematologica 33:480–487
NicholsonR.L.,
EpsteinL.1991; Adhesion of fungi to the plant surface.. In The Fungal Spore and Disease Initiation in Plants and Animals pp. 3–23ColeG.T.,
HochH.C.
Edited by New York: Plenum Press.;
PendlandJ.C.,
BouciasD.G.1991; Physiochemical properties of cell surfaces from the different developmental stages of the entomopathogenic hyphomyceteNomureae rileyi.
. Mycologia 83:264–272
ReuterG.,
AumannJ.,
WyssU.,
JanssonH.-B.,
SchauerR.1991; Panagrellus redivivus: Failure to find evidence for the occurrence and biosynthesis of sialic acids.. Experimental Parasito�logy 73:389–395
TeepeH.,
BöttgeJ.-A.,
WöstemeyerJ.1988; Isolation and electrophoretic analysis of surface proteins of the zygomyceteAbsidia glauca.
. FEBS Letters 234:100–106
TunlidA.,
JohanssonT.,
Nordbring-HertzB.1991a; Surface polymers of the nematode-trapping fungusArthrobotrys oligospora.
. Journal of General Microbiology 137:1231–1240
VeenhuisM.,
Nordbring-HertzB.,
HarderW.1985; An electron microscopical analysis of capture and initial stages of penetration of nematodes byArthrobotrys oligospora.
. Antonie van Leeuwenhoek 51:385–398
ZuckermanB.M.,
DicklowM.B.,
ColesG.C.,
Marban-MendozaN.1989; Loss of virulence of the endoparasitic fungusDrechmeria coniospora in culture.. Journal of Nematology 21:135–137