In vitro activity of teichomycin A 2 in comparison with penicillin and vancomycin against gram-positive cocci.

Teichomycin A2, a glycopeptide antibiotic from Actinoplanes teichomyceticus, was tested for its in vitro activity against 190 gram-positive cocci under variable test conditions. Minimum inhibitory concentrations were fairly insensitive to both changes of inoculum size and pH, but were higher on agar than in broth. Teichomycin was about as active as vancomycin against Staphylococcus aureus (both methicillin resistant and sensitive strains), slightly inferior to vancomycin against Staphylococcus epidermidis, and distinctly more active against Streptococcus faecalis.