Comparative genomics and evolutionary analysis of hydrophobins from three species of wood-degrading fungi.

Hydrophobins are small, secreted proteins playing important roles at different stages of fungal life cycles. Their characteristic feature is the presence of eight highly conserved cysteine residues. Here we present an inventory and evolutionary analysis of hydrophobin genes from three wood-degrading basidiomycetes, Phlebia brevispora, Ganoderma sp. and Bjerkandera adusta. The genomes of the three analyzed species are characterized by the presence of high copy numbers of hydrophobin genes. Results of the phylogenetic analysis of the identified proteins revealed that many of them share a high degree of sequence similarity and probably originated from a series of duplication events. The presence of several clusters of adjacent copies of the hydrophobin gene in a particular location in the genome further supports the interpretation that gene duplication has played a role in the evolution of hydrophobins in the analyzed species.