Isolation of Basidiobolus ranarum from ectotherms in Antwerp zoo with special reference to characterization of the isolated strains

Ten Basidiobolus ranarum ( = Basidiobolus haptosporus) strains, isolated fr om faeces of 102 different lower vertebrates (ectotherms) exhibited in Antw erp Zoo, or from their environment were studied for their temperature requi rements, haemolysis and other enzyme activities in vitro. All isolates grew well at 25 and 37 degrees C. Three strains that produced undulated zygospo re walls were haemolytic and positive for hyaluronidase. All the isolates p roduced urease, N-acetyl-beta-glucosaminidase, trypsin, lipase, lecithinase , gelatinase, collagenase and elastase, but failed to produce amylase, kera tinase and beta-glucosidase. Three isolates failed to produce phosphatase. Only one strain failed to produce DNase. Aesculin was not hydrolysed. Chiti nase activity was inconclusive. The results of this study illustrate the im portance of exotic animals kept in temperate regions as carriers of potenti ally pathogenic organisms. In addition to the morphological characteristics , the identification can be based on enzymatic profiles. Enzymatic activity detection may help to explain the pathogenic mechanism of the fungus.