<prompt> Bacteria not affected by streptogramins is ?E. coliStaphylococcuaureusLegionellaM. pneumoniae  <response>: Ans. is a i.e., E. coli Streptogramins are active against gram-positive cocci and organisms responsible for atypical pneumonia e.g., M. pneumoniae, Legionella spp., and Chlamydia pneumoniae, but largely inactive against gram-negative organisms. They are bactericidal against streptococci and many strains of staphylococci, but bacteriostatic against E. faecium. 