Table 2.

Morphologies exhibited by Gram-negative bacteria after NO treatment

P. aeruginosa

E. coli

■ Cellular debris Most often concentrated on surface in vicinity of cell Occasionally cell-associated ■ Membrane degradation Increased surface roughness Layered appearance Pores and crevices easily visualized ■ Cell collapse Lower height (< ~30 nm) Flatter appearance Some internal structures visible ■Cell lysis ■Decreased cell length ■Spheroplast formation ■Breakage ■Blebbing

■ Cellular debris Granule-like particles near cell Occasionally cell-associated ■ Membrane degradation Large increases in surface roughness Bumps and crevices in cell surface ■Cell collapse ■Cell lysis ■Decreased height and length ■Spheroplast formation ■ Damage at apical ends and along sides of cell Frequent collapse of apical ends Collapse of specific regions of the cell ○ Usually along edge of cell ○ Occasionally in cell interior ■Broken fimbriae