FIG 7.

Oxacillin reduces the level of cell wall-associated Sle1, and Sle1 cannot be detected in JE2mecA cells exposed to oxacillin. (A) Zymogram showing cell wall-associated proteins extracted from the indicated strains grown in the absence (–) or presence (+) of 8 μg ml⁻¹ oxacillin and then separated on an SDS gel containing heat-killed S. aureus JE2 cells. The inverted image of one representative gel of two biological independent experiments is shown. The positions of the molecular mass standards are indicated on the left (in kilodaltons). Asterisks indicate Atl bands that diminish in oxacillin-exposed JE2 cells lacking Sle1 or PBP2A. (B) Sle1 levels in cell wall extracts were determined by Western blotting in three biological replicates. Densitometry analysis was performed using Fiji. The obtained values were normalized to values obtained for the wild type and are displayed below the corresponding bands.