Genetic polymorphisms in three subtilisin-like protease isoforms (Pr1A, Pr1B, and Pr1C) from Metarhizium strains

Restriction fragment length polymorphisms (RFLP) were examined in three iso forms of a gene family encoding subtilisin-like proteases (Pr1A, Pr1B, and Pr1C) in several isolates of the entomopathogenic fungus Metarhizium anisop liae. RFLP variation was not observed in any of the Pr1 genes from isolates within the same genetically related group. Between genetically related gro ups and between isolates from disparate geographical areas, the greatest va riation in RFLP patterns was observed for Pr1A. When variation does occur a t Pr1B and Pr1C, it was generally observed at an EcoRI site. Metarhizium an isopliae var. majus strain 473 and a M. flavoviride isolate were most dissi milar in RFLP patterns at all Pr1 genes when compared to the M. anisopliae strains. We suggest that Pr1 genes represent a gene family of subtilisin-li ke proteases and that the Pr1A gene encodes for the ancestral subtilisin-li ke protease which has subsequently duplicated and rearranged within the gen ome.