Fig 3. Scanning electron microscopy of biofilms.

M. haemolytica (D153), grown in colorless RPMI 1640 (A, B, and C) and S. aureus Newbould 305 (NB305), grown in BHI broth (D, E, and F) on round glass coverslips in 24-well plates at 37°C for 48 h (NB305) to 72 h (D153). Biofilms grown on glass coverslips were fixed with 10% formalin (A and D), 2.5% glutaraldehyde (B and E), or Methacarn (C and F) fixative solutions for 48 h and samples were further processed for SEM examination. EPS layers on the top, in the middle, and in the bottom of biofilms (C and F) are shown by white arrows. One representative SEM biofilm image out of two independents experiments performed in triplicate wells are shown. (Bar = 4 μm; 5,000 magnification).