%0 Journal Article %A Jousson, Olivier %A Léchenne, Barbara %A Bontems, Olympia %A Capoccia, Sabrina %A Mignon, Bernard %A Barblan, Jachen %A Quadroni, Manfredo %A Monod, Michel %T Multiplication of an ancestral gene encoding secreted fungalysin preceded species differentiation in the dermatophytes Trichophyton and Microsporum %D 2004 %J Microbiology, %V 150 %N 2 %P 301-310 %@ 1465-2080 %R https://doi.org/10.1099/mic.0.26690-0 %I Microbiology Society, %X Dermatophytes are human and animal pathogenic fungi which cause cutaneous infections and grow exclusively in the stratum corneum, nails and hair. In a culture medium containing soy proteins as sole nitrogen source a substantial proteolytic activity was secreted by Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum canis. This proteolytic activity was 55–75 % inhibited by o-phenanthroline, attesting that metalloproteases were secreted by all three species. Using a consensus probe constructed on previously characterized genes encoding metalloproteases (MEP) of the M36 fungalysin family in Aspergillus fumigatus, Aspergillus oryzae and M. canis, a five-member MEP family was isolated from genomic libraries of T. rubrum, T. mentagrophytes and M. canis. A phylogenetic analysis of genomic and protein sequences revealed a robust tree consisting of five main clades, each of them including a MEP sequence type from each dermatophyte species. Each MEP type was remarkably conserved across species (72–97 % amino acid sequence identity). The tree topology clearly indicated that the multiplication of MEP genes in dermatophytes occurred prior to species divergence. In culture medium containing soy proteins as a sole nitrogen source secreted Meps accounted for 19–36 % of total secreted protein extracts; characterization of protein bands by proteolysis and mass spectrometry revealed that the three dermatophyte species secreted two Meps (Mep3 and Mep4) encoded by orthologous genes. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.26690-0