[Susceptibility of methicillin-resistant Staphylococcus aureus to various antibiotics. Classification by aminoglycoside-modifying enzymes and antibiotics active against MRSA].
MICs of 14 aminoglycoside antibiotics including 10 of those used clinically were determined against 50 strains of methicillin-resistant Staphylococcus aureus (MRSA) which had been isolated at a hospital in Osaka between 1986 and 1990. Arbekacin (ABK) inhibited the growth of all strains at less than or equal to 0.20-6.25 micrograms/ml, showing the most potent activities. Streptomycin showed good activities (1.56-6.25 micrograms/ml) against all strains except one resistant strain (greater than 100 micrograms/ml). Based on susceptibilities to kanamycin (98% resistant), tobramycin (84%), gentamicin (62%), amikacin (36%) and ABK (0%), MRSA strains were classified into 5 types; type 0 producing no aminoglycoside-modifying enzyme, type 1a producing APH(3'), type 1b producing AAD(4', 4''), type 2a producing APH (2'')/AAC(6') and APH(3'), and type 2b producing APH(2'')/AAC(6') and AAD(4', 4''). In addition to the aminoglycoside antibiotics, 13 known antibiotics including vancomycin (VCM) were found active against MRSA upon random screening. Taitomycin (0.013-0.050 micrograms/ml) was the most potent, and griseoluteins A and B (each 0.10-0.39 micrograms/ml), and macarbomycin (0.05-0.20 micrograms/ml) were more active than VCM (0.39-1.56 micrograms/ml). Novobiocin (less than or equal to 0.20-0.78 micrograms/ml) also showed good activities.
Kondo
S
S
Institute of Microbial Chemistry.
Ikeda
Y
Y
Hattori
S
S
Hamada
M
M
Takeuchi
T
T
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003982:Dibekacin / Q000031:analogs & derivatives / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D007612:Kanamycin / Q000494:pharmacology; D019868:Kanamycin Kinase; D016106:Methicillin Resistance; D009713:Nucleotidyltransferases / Q000378:metabolism; D010770:Phosphotransferases / Q000378:metabolism; D013211:Staphylococcus aureus / Q000145:classification / Q000187:drug effects* / Q000201:enzymology; D013307:Streptomycin / Q000494:pharmacology
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D003982:Dibekacin; D007612:Kanamycin; D010770:Phosphotransferases; D019868:Kanamycin Kinase; D009713:Nucleotidyltransferases; C420329:aminocyclitol adenylyltransferase; C420328:aminoglycoside 4'-adenylyltransferase; C023169:tobramycin adenylyltransferase; C020565:gentamicin 2''-nucleotidyltransferase; C031986:arbekacin; D013307:Streptomycin