Tea Tree Oil‐Induced Transcriptional Alterations in Staphylococcus aureus

• Published in: Phytotherapy research Vol. 27; no. 3; pp. 390 - 396
• Main Authors: Cuaron, Jesus A, Dulal, Santosh, Song, Yang, Singh, Atul K, Montelongo, Cesar E, Yu, Wanqin, Nagarajan, Vijayaraj, Jayaswal, Radheshyam K, Wilkinson, Brian J, Gustafson, John E
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.03.2013; Wiley Subscription Services, Inc
• Subjects: Anti-Bacterial Agents - pharmacology; antibacterial properties; bioinformatics; biosynthesis; cell division; cell walls; Down-Regulation - drug effects; ethanol; Ethanol - pharmacology; Gene Expression Regulation, Bacterial - drug effects; genes; heat inactivation; heat shock; heat stress; Melaleuca alternifolia; nodulation; pathogens; Staphylococcus aureus; Staphylococcus aureus - drug effects; Staphylococcus aureus - genetics; tea tree oil; Tea Tree Oil - pharmacology; Terpenes - pharmacology; transcription (genetics); Transcription, Genetic - drug effects; transcriptome; Transcriptome - drug effects; transcriptomics; translation (genetics); transporters; trees; vra
• ISSN: 0951-418X; 1099-1573
• DOI: 10.1002/ptr.4738

Tea tree oil (TTO) is a steam distillate of Melaleuca alternifolia that demonstrates broad‐spectrum antibacterial activity. This study was designed to document how TTO challenge influences the Staphylococcus aureus transcriptome. Overall, bioinformatic analyses (S. aureus microarray meta‐database) revealed that both ethanol and TTO induce related transcriptional alterations. TTO challenge led to the down‐regulation of genes involved with energy‐intensive transcription and translation, and altered the regulation of genes involved with heat shock (e.g. clpC, clpL, ctsR, dnaK, groES, groEL, grpE and hrcA) and cell wall metabolism (e.g. cwrA, isaA, sle1, vraSR and vraX). Inactivation of the heat shock gene dnaK or vraSR which encodes a two‐component regulatory system that responds to peptidoglycan biosynthesis inhibition led to an increase in TTO susceptibility which demonstrates a protective role for these genes in the S. aureus TTO response. A gene (mmpL) encoding a putative resistance, nodulation and cell division efflux pump was also highly induced by TTO. The principal antimicrobial TTO terpene, terpinen‐4‐ol, altered ten genes in a transcriptional direction analogous to TTO. Collectively, this study provides additional insight into the response of a bacterial pathogen to the antimicrobial terpene mixture TTO. Copyright © 2012 John Wiley & Sons, Ltd.