Effect of undecanoic acid on the production of exocellular lipolytic and keratinolytic enzymes by undecanoic acid-sensitive and -resistant strains of Trichophyton rubrum.

Effects of undecanoic acid on exocellular lipase, phospholipase A and keratinase activities of wild type undecanoic acid-sensitive (udas) and an undecanoic acid-resistant mutant (udar) of Trichophyton rubrum (derived from the udas strain) were determined. Undecanoic acid inhibited the production of exocellular lipase and keratinase but stimulated the production of exocellular phospholipase A in T. rubrum udas. Undecanoic acid did not affect exocellular lipase production by T. rubrum udar. Lipase production by the udar mutant was lower than that of the udas parent. No exocellular keratinase could be detected in the udar strain which had very low capacity for invasion of keratinized tissue.