Abstract
Whole-cell protein analysis of clinical isolates of Microsporum canis by polyacrylamide gel electrophoresis (PAGE) showed small but inconsistent differences in protein patterns. All clinical isolates closely resembled the (-) mating type of Arthroderma otae. A reference strain of A. otae (+) mating type from Japan gave a PAGE pattern which was distinct from those of the clinical isolates. Mating studies showed that the progeny of these reference (+) and (-) mating types had a variety of distinct protein patterns. Protein patterns can therefore distinguish between genetically different strains of M. canis (A. otae) suggesting that clinical isolates have a common clonal origin.