The inhibition effect of Chlorpromazine against the β-lactam resistance of MRSA

ABSTRACT

OBJECTIVE@#To investigate the gene related to β-lactam resistance and to confirm the mechanism about a synergy effect between CPZ and β-lactam antibiotics.@*METHODS@#To measure antibacterial activity, we performed a minimum inhibitory concentration (MIC) and synergy test. Transmission electron microscopy (TEM) was used in morphological analysis. To analyze gene expression, we conducted reverse transcriptase polymerase chain reaction (PCR).@*RESULTS@#We confirmed a synergy effect between CPZ and β-lactam antibiotics. Furthermore, we observed that CPZ affect the cell envelope of MRSA by using TEM. At the gene level, CPZ reduced the expression of resistance genes.@*CONCLUSIONS@#Through this result, we hypothesize that a decrease of resistance factor expressions was caused by CPZ because it disrupts the activity of a sensor protein located in the cell membrane.