Required for the proteolytic cleavage of the transcription factor pacC in response to alkaline ambient pH. Probably is the signaling protease that mediates the first proteolytic cleavage within the signaling protease box of pacC, yielding the 53 kDa 'open' conformation intermediate protein, which is committed to further processing. Required for virulence in invasive pulmonary aspergillosis (IPA). Belongs to the peptidase C2 family. PalB/RIM13 subfamily.