Oniciuc Elena-Alexandra, Cerca Nuno, Nicolau Anca I
Faculty of Food Science and Engineering, Dunarea de Jos University of GalatiGalati, Romania; Centre of Biological Engineering, Universidade do MinhoBraga, Portugal.
Centre of Biological Engineering, Universidade do Minho Braga, Portugal.
Front Microbiol. 2016 Mar 30;7:390. doi: 10.3389/fmicb.2016.00390. eCollection 2016.
Sixteen Staphylococcus aureus isolates originating from foods (eight from dairy products, five from fish and fish products and three from meat and meat products) were evaluated regarding their biofilms formation ability. Six strains (E2, E6, E8, E10, E16, and E23) distinguished as strong biofilm formers, either in standard Tryptic Soy Broth or in Tryptic Soy Broth supplemented with 0.4% glucose or with 4% NaCl. The composition of the biofilms formed by these S. aureus strains on polystyrene surfaces was first inferred using enzymatic and chemical treatments. Later on, biofilms were characterized by confocal laser scanning microscope (CLSM). Our experiments proved that protein-based matrices are of prime importance for the structure of biofilms formed by S. aureus strains isolated from food sources. These biofilm matrix compositions are similar to those put into evidence for coagulase negative staphylococci. This is a new finding having in view that scientific literature mentions exopolysaccharide abundance in biofilms produced by clinical isolates and food processing environment isolates of S. aureus.
对16株源自食品的金黄色葡萄球菌分离株（8株来自乳制品，5株来自鱼类和鱼制品，3株来自肉类和肉制品）的生物膜形成能力进行了评估。在标准胰蛋白胨大豆肉汤或添加了0.4%葡萄糖或4%氯化钠的胰蛋白胨大豆肉汤中，有6株菌株（E2、E6、E8、E10、E16和E23）被鉴定为强生物膜形成菌。首先通过酶处理和化学处理推断这些金黄色葡萄球菌菌株在聚苯乙烯表面形成的生物膜的组成。随后，用共聚焦激光扫描显微镜（CLSM）对生物膜进行表征。我们的实验证明，基于蛋白质的基质对于从食品来源分离的金黄色葡萄球菌菌株形成的生物膜结构至关重要。这些生物膜基质组成与凝固酶阴性葡萄球菌的情况相似。鉴于科学文献提到临床分离株和食品加工环境分离株产生的金黄色葡萄球菌生物膜中胞外多糖含量丰富，这是一个新发现。
