Molecular characterisation of the fish-pathogenic fungus Aphanomyces invadans
2003 (English)In: Journal of Fish Diseases, Vol. 26, no 5, 263-275 p.Article in journal (Refereed) Published
Aphanomyces invadans (Saprolegniaceae) is a peronosporomycete fungusassociated with the serious fish disease, epizootic ulcerative syndrome ( EUS), also known as mycotic granulomatosis. In this study, interspecific relationships were examined between A. invadans isolates and other aquatic animal pathogenic Saprolegniaceae, and saprophytic Saprolegniaceae from EUS-affected areas. Restriction fragment length polymorphisms and sequences of ribosomal DNA confirmed that A. invadans is distinct from all other species studied. A sequence from the internal transcribed spacer region ITS1, unique to A. invadans, was used to design primers for a PCR-based diagnostic test. Intraspecific relationships were also examined by random amplification of polymorphic DNA using 20 isolates of A. invadans from six countries. The isolates showed a high degree of genetic homogeneity using 14 random ten-mer primers. This provides evidence that the fungus has spread across Asia in one relatively rapid episode, which is consistent with reports of outbreaks of EUS. Physiological distinctions between A. invadans and otherAphanomyces species based on a data set of 16 growth parameters showed remarkable taxonomic congruence with the molecular phylogeny.
Place, publisher, year, edition, pages
2003. Vol. 26, no 5, 263-275 p.
IdentifiersURN: urn:nbn:se:uu:diva-47479DOI: 10.1046/j.1365-2761.2003.00448.xISI: 000183601800002OAI: oai:DiVA.org:uu-47479DiVA: diva2:75386