Extracellular lipase and proteinase of Basidiobolus haptosporus: possible role in subcutaneous mycosis.

Properties of proteinase(s) and phospholipase A in dialyzed culture filtrate of Basidiobolus haptosporus were studied. Lysolecithin, one of the hydrolytic products of phosphatidyl choline by phospholipase A was prepared and found able to hemolyse human red blood cells and 'clear' rat skin and muscle homogenates. The proteinase was able to digest human serum proteins. The pathogenic mechanism employed by this fungus may involve hydrolysis of lecithin to yield lysolecithin, which destroys cell membranes thereby liberating intracellular contents. The protein components of these contents are then digested by the proteinase(s) yielding amino acids which along with other metabolites serve as nutrients for the growth of the pathogen.