Secreted subtilisin gene family in Trichophyton rubrum.
Secreted proteases constitute potential virulence factors of dermatophytes. A total of seven genes encoding putative serine proteases of the subtilisin family (SUB) were isolated in Trichophyton rubrum. Based on sequence data and intron-exon structure, a phylogenetic analysis of subtilisins from T. rubrum and other fungi revealed a presumed ancestral lineage comprising T. rubrum SUB2 and Aspergillus SUBs. All other SUBs (SUB1, SUB3-7) are dermatophyte-specific and have apparently emerged more recently, through successive gene duplication events. We showed that two subtilisins, Sub3 and Sub4, were detected in culture supernatants of T. rubrum grown in a medium containing soy protein as a sole nitrogen source. Both recombinant enzymes produced in Pichia pastoris are highly active on keratin azure suggesting that these proteases play an important role in invasion of keratinised tissues by the fungus. The set of deduced amino acid sequences of T. rubrum SUB ORFs allowed the identification of orthologous Subs secreted by other dermatophyte species using proteolysis and mass spectrometry.
Jousson
Olivier
O
Dermatology Service (DHURDV), Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
Léchenne
Barbara
B
Bontems
Olympia
O
Mignon
Bernard
B
Reichard
Utz
U
Barblan
Jachen
J
Quadroni
Manfredo
M
Monod
Michel
M
D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D005091:Exons; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005800:Genes, Fungal / Q000235:genetics; D007438:Introns; D013058:Mass Spectrometry / Q000379:methods; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D010802:Phylogeny; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D013379:Substrate Specificity; D020860:Subtilisin / Q000235:genetics* / Q000378:metabolism; D014249:Trichophyton / Q000235:genetics*
D018076:DNA, Complementary; D004271:DNA, Fungal; D005656:Fungal Proteins; D011994:Recombinant Proteins; D020860:Subtilisin