For over 100 years, the chemical compounds have been isolated from medicinal plants served as models CP-466722 for many drugs clinically proven and is now re-evaluated as antimicrobial agents. Cryptotanshinone is an important Tanshinone Dan Shen, the root of Salvia miltiorrhiza Bunge. CT has confinement antimicrobial activity against a broad spectrum of Gram-positive bacteria, Lich S. aureus and Gram-negative bacteria and other microorganisms. Although CT showed a relatively high activity T against S. aureus, there were no reports of the inhibitory mechanisms of CT against S. aureus. Transcription profiling with Affymetrix GeneChips generated used to identify genes of S. aureus, which are induced in response to the antibiotics vancomycin, oxacillin, d cycloserine or bacitracin.
Transcriptional Raltitrexed profiles of microorganisms treated with an inhibitor, k Nnte valuable information mechanism both for characterization to provide means and for determining the inhibition. In this report, the antimicrobial activity of t M and investigate Aligned mechanisms of action of CT against S. aureus, we tested the minimum inhibitory concentration of CT versus 21 St Strains of S. aureus, and the use of Affymetrix GeneChip analysis of differentially expressed genes to identify S. aureus treated with sub-inhibitory concentrations of CT. AndMethods 2.Materials 2.1. Bakterienst mme And materials. St mme Was used by S. aureus in this study consisted of 20 clinical isolates of H Pital first Jilin University, which have different Anf Susceptibility obtained against 12 antibiotics and the standard strain ATCC 25923 by the China Medical Culture Collection Center.
Mueller Hinton II Broth and Mueller Hinton agar were purchased from BD. CT was purchased from the center of the China Medical Culture Collection and Solutions of different concentrations were dissolved in dimethyl sulfoxide gel. 2.2. Susceptibility testing to antibiotics. The minimum inhibitory concentration of CT against 21 strains St S. aureus were determined in triplicate by broth microdilution or macrodilution with double serial dilutions in MHB II, CLSI / NCCLS M100 S15. MICs were defined as the lowest concentration at which no visible growth was observed. The minimum concentration of CT, 90% of isolates tested, was locked defined as MIC90. 2.3. synergistic study. A standard checkerboard test was conducted to evaluate the interaction of the combination against the strain of S.
. Aureus ATCC 25923 by an established method The fractional inhibitory concentration index was gem a previously described method calculated. FIC index between two compounds diameter equal to or less than 0.5 is a synergy FIC index between 0.5 and 2, and the same two ormore indifference as Fici Antagonism is considered. 2.4. Growth curves. Strain of S. aureus ATCC 25923 was grown to an optical density of 0.3 at 600 nm in MHB II, and 100 ml aliquots were then divided into five 500 ml Erlenmeyer flask. CT was added to four cultures to obtain final concentrations of 1/4 MIC × semi × MIC, MIC, MIC and 2 × respectively. The final concentration of DMSO was used 1%, and the culture and the embroidered with 1% DMSO was complements erg. The cultures were incubated, and c.