In vitro activities of two glycylcyclines against gram-positive bacteria.
The glycylcyclines designated CL 329,998 and CL 331,002 are N,N-dimethylglycylamido derivatives of minocycline and 6-demethyl-6-deoxytetracycline, respectively. In vitro activities of these two antimicrobial agents were compared with those of tetracycline, minocycline, and seven other antimicrobial agents against 412 gram-positive organisms. Both new drugs were significantly more active than minocycline against methicillin-resistant Staphylococcus aureus (MICs for 90% of isolates tested, 0.25 and 0.5 microgram/ml versus 4 micrograms/ml). CL 329,998 inhibited all streptococci, lactobacilli, and Leuconostoc spp. at concentrations of < or = 0.5 microgram/ml, with CL 331,002 slightly less active against some species. All enterococci, including minocycline-resistant and multidrug-resistant isolates, were inhibited at < or = 0.5- and < or = 1.0-microgram/ml concentrations of the new drugs, respectively. Only bacteriostatic activity was evident by time-kill curves. The two glycylcyclines demonstrated activities in vitro that were superior to those of minocycline against several gram-positive bacterial species, and at relatively low concentrations, they inhibited isolates resistant to both tetracycline and minocycline.
Eliopoulos
G M
GM
Department of Medicine, New England Deaconess Hospital, Boston, Massachusetts 02215.
Wennersten
C B
CB
Cole
G
G
Moellering
R C
RC
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D008911:Minocycline / Q000031:analogs & derivatives* / Q000494:pharmacology; D013754:Tetracyclines / Q000494:pharmacology*; D013997:Time Factors
D000900:Anti-Bacterial Agents; D013754:Tetracyclines; C087533:CL 331002; C087532:N,N-dimethylglycylamidominocycline; D008911:Minocycline