sentence: For our experiments , CAPE ( Sigma-Aldrich , Buchs , Switzerland ) ; sodium dodecyl sulfate ; crystal violet ; peptone ; yeast extract ( Merck , Germany ) ; agar-agar ( Fluka , Buchs , Switzerland ) ; a modified version of RPMI 1640 medium ( containing dextrose 1.8 % ( w / v ) , MOPS 3.4 % ( w / v ) , and adenine 0.002 % ( w / v ) ) ( Sigma-Aldrich , St. Louis , MI , USA ) ; potassium dihydrogen phosphate ; disodium hydrogen phosphate ( Reanal , Budapest , Hungary ) ; dimethyl sulfoxide ; ethanol ( VWR Chemicals , Paris , France ) ; sodium chloride ( VWR Chemicals , Debrecen , Hungary ) ; glucose ( VWR Chemicals , Leuven , Belgium ) ; adenine ; calcium chloride ; magnesium chloride ; potassium chloride ( Scharlau Chemie S.A , Sentmenat , Spain ) ; Z-VAD-FMK ( Biovision , Milpitas , CA , USA ) ; glutardialdehyde solution ; osmium tetroxide ; propylene oxide ; Durcupan ( R ) ACM components A / M , B , C , and D ( Sigma-Aldrich , Darmstadt , Germany ) ; 0.22 µ m vacuum filters ( Merck Millipore , Guyancourt , France ) ; sterile 96-well microtiter plates for susceptibility testing ( Costar , Phoenix , AZ , USA ) and for biofilm assays ( Sarstedt AG & Co. KG , N ü mbrecht , Germany , Catalog number : 83.3924.500 ) ; CF 488A Annexin V and PI apoptosis Kit ( Biotium , Fremont , CA , USA ) ; and methanol ( Chemolab Ltd ., Budapest , Hungary ) were used .