ABSTRACT
Emodin has a strong antibacterial activity, including methicillin-resistant Staphylococcus aureus (MRSA). However, the mechanism by which emodin induces growth inhibition against MRSA remains unclear. In this study, the isobaric tags for relative and absolute quantitation (iTRAQ) proteomics approach was used to investigate the modes of action of emodin on a MRSA isolate and methicillin-sensitive S. aureus ATCC29213(MSSA). Proteomic analysis showed that expression levels of 145 and 122 proteins were changed significantly in MRSA and MSSA, respectively, after emodin treatment. Comparative analysis of the functions of differentially expressed proteins between the two strains was performed via bioinformatics tools blast2go and STRING database. Proteins related to pyruvate pathway imbalance induction, protein synthesis inhibition, and DNA synthesis suppression were found in both methicillin-sensitive and resistant strains. Moreover, Interference proteins related to membrane damage mechanism were also observed in MRSA. Our findings indicate that emodin is a potential antibacterial agent targeting MRSA via multiple mechanisms.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Emodin/pharmacology , Gene Expression/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Bacterial Proteins/metabolism , Cathartics/pharmacology , Computational Biology , Drug Repositioning , Gene Expression Profiling , Gene Regulatory Networks/drug effects , Methicillin-Resistant Staphylococcus aureus/genetics , Methicillin-Resistant Staphylococcus aureus/growth & development , Methicillin-Resistant Staphylococcus aureus/metabolism , Microbial Sensitivity Tests , ProteomicsABSTRACT
As the dilution procedure was applied, a simple, rapid and cost-effective high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of aflatoxin B1, B2, G1, and G2 was successfully by performed in a total 83 samples of 10 traditional Chinese medicines (TCMs), which were collected from 5 different hospital pharmacies and 5 different medical stores in Guangzhou city. Matrix effects of these 10 TCMs were ranged from 80.23% to 115.5% in low, intermediate and high concentration levels, indicating that the negative effect was overcome in this study. Meanwhile, the analysis method was proved to be stable and reliable during the whole analysis using Semen Armeniacae Amarum spiked 3 concentration levels of standard solution as quality control samples and the RSD < 6.6% was obtained. The contamination levels of 83 investigated samples were 13.89% and 17.02% in hospital pharmacies and medical stores, respectively. The result was presented to provide relevant reference and supplement to those researchers in TCMs analysis and screening.
