Pawar D M, Rossman M L, Chen J
Department of Food Science and Technology, The University of Georgia, Griffin, GA 30223-1797, USA.
J Appl Microbiol. 2005;99(2):418-25. doi: 10.1111/j.1365-2672.2005.02499.x.
The objectives of this study were to evaluate the role of curli in assisting the cells of enterohaemorrhagic Escherichia coli (EHEC) in attaching to abiotic surfaces and to determine the influence of cell-surface contact time on the efficiency of the attachment.
Three pairs of EHEC cultures, each with a curli-expressing and a noncurli-expressing variant (O111:H- 7-57C+ and O157:H7 5-9C-, O157:H7 5-11C+ and 5-11C-, as well as O103:H2 7-52C+ and 7-52C-), were allowed to interact with polystyrene, glass, stainless steel and rubber surfaces at 28 degrees C for 24 h (short-term attachment) or 7 days (long-term attachment). The quantities of the cells that attached to the surfaces were measured daily in the long-term attachment study, and in 4 h intervals in the short-term attachment study. Quantification of the cells that attached to the surfaces was accomplished with a crystal violet binding assay. The results of the long-term attachment study indicated that 7-57C+ attached to the polystyrene and glass surfaces more efficiently (P < 0.05) than did 5-9C-. The curli-expressing variant of 5-11 possessed a better ability to adhere to the polystyrene and glass surfaces than did its noncurli-expressing counterpart (P < 0.05). The differences in attachment between 7-52C+ and 7-52C- on polystyrene and stainless steel surfaces were statistically significant (P < 0.05). However, the attachment of the pair on the glass surfaces was statistically insignificant (P > 0.05). In addition, the two members of all three EHEC pairs attached equally well to rubber surfaces (P > 0.05). In the short-term attachment study, only the pair of 7-52 attached differently on glass and stainless steel surfaces (P < 0.05).
These results suggest that curli could be an important cell surface component to mediate the attachment of some EHEC cells to certain abiotic surfaces. Cell-surface contact time could have a significant influence on EHEC attachment to abiotic surfaces.
The study signifies a possible role of curli in assisting the cells of EHEC in attaching to food-contact surfaces. It underlines the importance of cleaning and sanitizing food-contact surfaces regularly and thoroughly, and of identifying chemical agents that can effectively remove the attached EHEC cells from these surfaces.
本研究的目的是评估卷曲菌毛在协助肠出血性大肠杆菌（EHEC）细胞附着于非生物表面中的作用，并确定细胞表面接触时间对附着效率的影响。
三对EHEC培养物，每对均有一个表达卷曲菌毛的变体和一个不表达卷曲菌毛的变体（O111:H- 7-57C+和O157:H7 5-9C-、O157:H7 5-11C+和5-11C-，以及O103:H2 7-52C+和7-52C-），使其在28℃下与聚苯乙烯、玻璃、不锈钢和橡胶表面相互作用24小时（短期附着）或7天（长期附着）。在长期附着研究中每天测量附着在表面的细胞数量，在短期附着研究中每隔4小时测量一次。通过结晶紫结合试验对附着在表面的细胞进行定量。长期附着研究结果表明，7-57C+比5-9C-更有效地附着于聚苯乙烯和玻璃表面（P < 0.05）。5-11的表达卷曲菌毛的变体比其不表达卷曲菌毛的对应变体具有更好的附着于聚苯乙烯和玻璃表面的能力（P < 0.05）。7-52C+和7-52C-在聚苯乙烯和不锈钢表面的附着差异具有统计学意义（P < 0.05）。然而，该对在玻璃表面的附着在统计学上无显著差异（P > 0.05）。此外，所有三对EHEC的两个成员在橡胶表面的附着情况相同（P > 0.05）。在短期附着研究中，只有7-52这一对在玻璃和不锈钢表面的附着情况不同（P < 0.05）。
这些结果表明卷曲菌毛可能是介导某些EHEC细胞附着于某些非生物表面的重要细胞表面成分。细胞表面接触时间可能对EHEC附着于非生物表面有显著影响。
该研究表明卷曲菌毛在协助EHEC细胞附着于食品接触表面方面可能发挥作用。它强调了定期彻底清洁和消毒食品接触表面以及识别能够有效从这些表面去除附着的EHEC细胞的化学试剂的重要性。
