Bandara H M H N, Cheung Becky P K, Watt Rory M, Jin Li Jian, Samaranayake Lakshman P
Oral Bioscience, Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, Sai Ying Pun, Hong Kong.
J Investig Clin Dent. 2013 Aug;4(3):186-99. doi: 10.1111/jicd.12048. Epub 2013 Jun 14.
To investigate the time- and concentration-dependent effects of Escherichia coli biofilm supernatant on Candida biofilm development, and to assess the effect of E. coli supernatant on Candida albicans hypha-specific genes (HSGs) expression.
The effect of E. coli biofilm supernatant on six Candida spp. was assessed by tetrazolium salt (XTT) reduction assay, scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM). The effect of biofilm supernatant on the expression of C. albicans HSGs (ECE1, HWP1, HYR1, RBT1, RBT4, ALS3, and ALS8) and transcription factors (CPH1, CPH2, EFG1, TEC1, RAS1, TUP1, NRG1 and RFG1) was evaluated with real-time polymerase chain reaction (PCR).
Escherichia coli biofilm secretory products significantly inhibited C. albicans, C. glabrata, C. tropicalis and C. krusei biofilms at 24 h and all Candida spp. at 48 h (P < 0.05), and SEM and CLSM confirmed these data. HSGs RBT1 and RBT4 were mostly up-regulated and ECE1, HWP1 and HYR1 were mostly down-regulated. ALS3 was totally suppressed. All HSGs were down-regulated at 48 h (P < 0.05). NRG1, RFG1 and EFG1, CPH1 and TEC1, and TUP1 and CPH2 showed similar expression trends and all were down-regulated at 48 h (P < 0.05).
Escherichia coli secretory elements significantly impair Candida biofilm development possibly by modulating HSGs and its transcriptional regulation.
研究大肠杆菌生物膜上清液对念珠菌生物膜形成的时间和浓度依赖性影响，并评估大肠杆菌上清液对白色念珠菌菌丝特异性基因（HSGs）表达的影响。
采用四氮唑盐（XTT）还原试验、扫描电子显微镜（SEM）和共聚焦激光扫描显微镜（CLSM）评估大肠杆菌生物膜上清液对六种念珠菌属的影响。通过实时聚合酶链反应（PCR）评估生物膜上清液对白色念珠菌HSGs（ECE1、HWP1、HYR1、RBT1、RBT4、ALS3和ALS8）及转录因子（CPH1、CPH2、EFG1、TEC1、RAS1、TUP1、NRG1和RFG1）表达的影响。
大肠杆菌生物膜分泌产物在24小时时显著抑制白色念珠菌、光滑念珠菌、热带念珠菌和克鲁斯念珠菌生物膜，在48小时时抑制所有念珠菌属生物膜（P<0.05），SEM和CLSM证实了这些数据。HSGs中的RBT1和RBT4大多上调，而ECE1、HWP1和HYR1大多下调。ALS3完全被抑制。所有HSGs在48小时时均下调（P<0.05）。NRG1、RFG1和EFG1、CPH1和TEC1，以及TUP1和CPH2表现出相似的表达趋势，且在48小时时均下调（P<0.05）。
大肠杆菌分泌成分可能通过调节HSGs及其转录调控显著损害念珠菌生物膜的形成。
