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Introduction: The genus Malassezia comprises 17 species of commensal and pathogenic yeasts of homeotherms animal skin. The most common species are M. furfur, M. globosa, and M. sympodialis in humans and M. pachydermatis in animals. However, some publications have reported potentially serious human infections by M. pachydermatis in individuals with risk factors and the isolation of human species from domestic animals. Given the scarcity of information about their capacity for transmission between hosts and zoonotic potential, the aim of the present study was to physiologically and molecularly characterize Malassezia spp. isolates obtained from canines and their human owners. Materials and Methods: An experimental study was conducted at the Veterinary Clinic of Universidad de Ciencias Aplicadas y Ambientales of Bogotá (Colombia) from July 2015 to December 2016. Phenotypic identification and molecular characterization via the amplification of the 5.8S rDNA-ITS2 and 26S rDNA gene regions, nucleic acid sequencing, and phylogenetic analyses were performed on isolates originating from canines with otitis externa and from the skin of healthy owners compatible with Malassezia spp. Results: Eighty samples were cultured, of which 32 (40%) were suggestive of Malassezia spp. A total of 29 out of 46 (63%) isolates in canines and 3 out of 34 (9%) isolates in humans corresponded entirely with M. pachydermatis. Isolates from the canines and their owners presented similar behavior in biochemical and phospholipase activity tests, 100% molecular sequence identities, and close proximity in the phylogenetic trees. Conclusion: The isolation of M. pachydermatis from humans and their dogs with identity based on biochemical, physiological, molecular, and phylogenetic perspectives indicate the How to cite this paper:

Sporulation involves inducing scores of genes in a temporally and spatially coordinated cell development programme. Its initiation is controlled by an expanded two-component signal transduction system, termed a phosphorelay. The Spo0A response regulator is the master control element in the decision to sporulate, consisting of a receiver or phosphoacceptor domain and an effector or transcription activation domain having a high degree of sequence conservation. This study examined long-term Spo0A protein evolution for determining whether concerted evolution or purifying selection was the major factor in its evolution. The proportion of synonymous (pS) and non-synonymous nucleotide (pN) differences between Spo0A genes from 28 bacterial species was analysed. DIVERGE software was used for evaluating site-specific amino acids before phylogenetic divergence between Bacillus and Clostridium for detecting site-selective constrains operating on the Spo0A protein. Evolutionary Trace software was used for tracing the phylogenetic markers for this protein.

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