The binding of Thermomyces lanuginosa lipase and its mutants [TLL(S146A), TLL(W89L), TLL(W117F, W221H, W260H)] to the mixed micelles of cis-parinaric acid/ sodium taurodeoxycholate at pH led to the quenching of the intrinsic tryptophan fluorescence emission (300–380 nm) and to a simultaneous increase in the cis-parinaric acid fluorescence emission (380–500 nm). These findings were used to characterize the Thermomyces lanuginosa lipase/cisparinaric acid interactions occurring in the presence of sodium taurodeoxycholate
