Xu Zhenbo, Liang Yanrui, Lin Shiqi, Chen Dingqiang, Li Bing, Li Lin, Deng Yang
College of Food Science and Technology, South China University of Technology, Guangzhou, 510640, China.
Department of Biomedical Science, University of Maryland, Baltimore, MD, 21201, USA.
Curr Microbiol. 2016 Oct;73(4):474-82. doi: 10.1007/s00284-016-1081-1. Epub 2016 Jun 21.
Staphylococcus aureus (S. Aureus) is a common food-borne pathogenic microorganism. Biofilm formation remains the major obstruction for bacterial elimination. The study aims at providing a basis for determining S. aureus biofilm formation. 257 clinical samples of S. aureus isolates were identified by routine analysis and multiplex PCR detection and found to contain 227 MRSA, 16 MSSA, 11 MRCNS, and 3 MSCNS strains. Two assays for quantification of S. aureus biofilm formation, the crystal violet (CV) assay and the XTT (tetrazolium salt reduction) assay, were optimized, evaluated, and further compared. In CV assay, most isolates formed weak biofilm 74.3 %), while the rest formed moderate biofilm (23.3 %) or strong biofilm (2.3 %). However, most isolates in XTT assay showed weak metabolic activity (77.0 %), while the rest showed moderate metabolic activity (17.9 %) or high metabolic activity (5.1 %). In this study, we found a distinct strain-to-strain dissimilarity in terms of both biomass formation and metabolic activity, and it was concluded from this study that two assays were mutual complementation rather than being comparison.
金黄色葡萄球菌是一种常见的食源致病性微生物。生物膜的形成仍然是细菌清除的主要障碍。本研究旨在为确定金黄色葡萄球菌生物膜的形成提供依据。通过常规分析和多重PCR检测对257株金黄色葡萄球菌临床分离株进行鉴定，发现其中包含227株耐甲氧西林金黄色葡萄球菌（MRSA）、16株甲氧西林敏感金黄色葡萄球菌（MSSA）、11株耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）和3株甲氧西林敏感凝固酶阴性葡萄球菌（MSCNS）菌株。对两种定量金黄色葡萄球菌生物膜形成的检测方法，即结晶紫（CV）检测法和XTT（四氮唑盐还原）检测法进行了优化、评估并进一步比较。在CV检测法中，大多数分离株形成弱生物膜（74.3%），其余形成中度生物膜（23.3%）或强生物膜（2.3%）。然而，在XTT检测法中，大多数分离株显示弱代谢活性（77.0%），其余显示中度代谢活性（17.9%）或高代谢活性（5.1%）。在本研究中，我们发现不同菌株在生物量形成和代谢活性方面存在明显差异，并且从本研究得出结论，这两种检测方法是相互补充而非相互比较。
