To realize the use of nematode-trapping fungi for
biocontrol of plant parasitic nematodes, further research to
enhance nematode trapping and killing rates will be needed,
and thus it is important to better understand the role of
serine proteases as pathogenicity mediators. In this study,
we partially purified a cuticle-degrading serine protease
from the nematode-trapping fungus, Arthrobotrys musiformis,
assessed its catalytic activity, and subsequently
cloned and characterized the serine protease-coding gene.
We termed this gene, AmSP1, and further conducted
phylogenetic analysis of the AmSP1 protease sequence
against five allied nematode-trapping fungi, as well as selection
force analysis of the dN/dS ratio of the entire AmSP1
coding sequence and allied serine protease gene sequences,
in order to better understand the evolutionary development
of the cuticle-degrading serine protease gene (Graur and Li
2000; Futuyma 2005; Yang et al. 2007a,c, 2008; Librado and
Rozas 2009; Tamura et al. 2013).