[Influence of Different Type of Surfactant on Bacteriolytic Activity of Lysozyme]

The influence ofvarious surfactants (anionic sodium dodecyl sulfate, SDS, cationic dodecyltrimethylarnmonium bromide, DTAB, and zwitterionic cocoamidopropylbetaine, CAPB) on the activity of the chicken egg lysozyme is investigated. Lysis of Gram-positive bacteria by the enzyme was carried out at pH 7.2 and ionic strength of 0.15 M. It was found that at low SDS and DTAB concentrations (less than 1 x 10(-5) M) the bacteriolytic activity increases by 30-140%. At higher concentrations (1 x 10(-5) - 1 x 10(4) M) the activity returns to the level observed in the absence of the surfactants. The elevated activity correlated with the formation of hydrophobic lysozyme-surfactant complexes. Introduction of CAPB at concentrations above 1 x 10(-5) M sig, nificantly diminished the bacteriolytic activity due to CAPB induced aggregation of lysozyme.