Extracellular enzymatic activity ofMicrosporum canis isolates

The enzymatic activity of 70 feline and canineMicrosporum canis isolates was determined by the Api-Zym^® test. The liquid phase of cultures, inoculated into Tryptic Soy Broth, was used to examine 19 enzymes. Considerable differences were observed among the extracellular enzymatic patterns. All the isolates produced alkaline phosphatase and beta-glucosidase, while lipase (C14), trypsin, chymotrypsin, beta-glucuronidase, and alpha-fucosidase activity was never revealed. Esterase (C4) activity was present in 57 samples (81%), esterase lipase (C8) in 31 (44%), leucine arylamidase in 35 (50%), valine arylamidase and cystine arylamidase in 7 (10%), acid phosphatase in 64 (91%), naphthol-AS-BI-phosphohydrolase in 60 (86%), alpha-galactosidase in 5 (7%), beta-galactosidase in 6 (8%), alpha-glucosidase in 25 (36%), N-acetyl-beta-glucosaminidase in 41 (58%), and alpha-mannosidase in 51 (73%). The beta-galactosidase activity ofM. canis has not been reported previously. Remarkable variations of intensity for each enzymatic activity were also detected. It is believed that these results could provide basic data for further investigations on the pathogenic role of enzymes secreted byM. canis.