Effects of the garlic compounds diallyl sulphide and diallyl disulphide onarylamine N-acetyltransferase activity in Klebsiella pneumoniae

Arylamine N-acetyltransferase (NAT) activities with 2-aminofluorene (2-AF) were determined in the bacterium Klebsiella pneumoniae. Cytosols or suspens ions of K, pneumoniae with or without specific concentrations of diallyl su lphide (DAS) or diallyl disulphide (DADS) as co-treatment showed different percentages of 2-AF acetylation, The data indicated that there was decrease d NAT activity associated with increased levels of DAS or DADS in K, pneumo niae, In growth studies on K, pneumoniae it was demonstrated that DAS or DA DS elicited a dose-dependent bacteriocide effect on K, pneumoniae, For the cytosol examinations, the apparent values of K-m and V-max were 0.96 +/- 0. 09 mM and 7.87 +/- 0.79 nmol min(-1) mg(-1) protein, respectively, for 2-AF , However, when DAS or DADS was added to the reaction mixtures, the apparen t values of K-m and V-max were 0.16 +/- 0.04 mM and 0.99 +/- 0.16 nmol min( -1) mg(-1) protein with DAS, respectively, and 0.14 +/- 0.18 mM and 0.85 +/ - 0.10 nmol min(-1) mg(-1) protein with DADS, respectively, for 2-AF, For t he intact bacteria examination, the apparent values of K-m and V-max were 0 .57 +/- 0.06 mM and 2.00 +/- 0.14 nmol min(-1) per 10 x 10(10) CFU, respect ively, for 2-AF, However, when DAS or DADS was added to the reaction mixtur es, the apparent of values of K-m and V-max were 0.41 +/- 0.04 mM and 1.30 +/- 0.10 nmol min(-1) per 10 x 10(10) CFU with DAS, respectively, and 0.34 +/- 0.04 mM and 1.08 +/- 0.08 nmol min(-1) per 10 x 10(10) CFU with DADS, r espectively, for 2-AF, This report is the first demonstration to show that the garlic components DAS and DADS would affect K, pneumoniae growth and NA T activity. Copyright (C) 1999 John Wiley & Sons, Ltd.