Transcriptional and functional analysis shows sodium houttuyfonate-mediated inhibition of autolysis in Staphylococcus aureus

• Published in: Molecules (Basel, Switzerland) Vol. 16; no. 10; pp. 8848 - 8865
• Main Authors: Liu, Guoxing, Xiang, Hua, Tang, Xudong, Zhang, Kaiyu, Wu, Xiuping, Wang, Xuelin, Guo, Na, Feng, Haihua, Wang, Guangming, Liu, Lihui, Shi, Qiyun, Shen, Fengge, Xing, Mingxun, Yuan, Peng, Liu, Mingyuan, Yu, Lu
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 21.10.2011; MDPI
• Subjects: Alkanes - pharmacology; Anti-Bacterial Agents - pharmacology; Antimicrobial agents; Bacteria; Bacterial Proteins - metabolism; Bacteriolysis - drug effects; Biofilms; Biofilms - drug effects; Drugs, Chinese Herbal - pharmacology; Gene Expression Regulation, Bacterial - drug effects; GeneChip; Membrane Proteins - drug effects; Membrane Proteins - metabolism; Microbial Sensitivity Tests; N-Acetylmuramoyl-L-alanine Amidase - genetics; N-Acetylmuramoyl-L-alanine Amidase - metabolism; Nosocomial infections; Oligonucleotide Array Sequence Analysis; Plant Extracts - pharmacology; Sodium; sodium houttuyfonate; Staphylococcus aureus; Staphylococcus aureus - drug effects; Staphylococcus aureus - genetics; Staphylococcus aureus - metabolism; Staphylococcus infections; Streptococcus infections; Sulfites - pharmacology; transcription; Transcription, Genetic - drug effects; Zoonoses; China
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules16108848

Sodium houttuyfonate (SH), an addition compound of sodium bisulfite and houttuynin, showed in vitro antibacterial activity against 21 Staphylococcus aureus (S. aureus) strains grown in planktonic cultures. Microarray results showed decreased levels of autolysin atl, sle1, cidA and lytN transcripts in the SH-treated strain as compared to the control strain, consistent with the induction of the autolytic repressors lrgAB and sarA and with the downregulation of the positive regulators agrA and RNAIII. Triton X-100-induced autolysis was significantly decreased by SH in S. aureus ATCC 25923, and quantitative bacteriolytic assays and zymographic analysis demonstrated SH-mediated reduction of extracellular murein hydrolase activity in these cells. Anti-biofilm assay showed that SH is poorly active against S. aureus grown in biofilm cultures, whereas SH diminished the amounts of extracellular DNA (eDNA) of S. aureus in a dose-dependent manner, which suggested that SH may impede biofilm formation by reducing the expression of cidA to inhibit autolysis and eDNA release in the early phase. Some of the microarray results were confirmed by real-time RT-PCR.