Ren D, Bedzyk L A, Thomas S M, Ye R W, Wood T K
Departments of Chemical Engineering and Molecular and Cell Biology, University of Connecticut, 191 Auditorium Road, Storrs, CT 06269-3222, USA.
Appl Microbiol Biotechnol. 2004 May;64(4):515-24. doi: 10.1007/s00253-003-1517-y. Epub 2004 Jan 16.
DNA microarrays were used to study the gene expression profile of Escherichia coli JM109 and K12 biofilms. Both glass wool in shake flasks and mild steel 1010 plates in continuous reactors were used to create the biofilms. For the biofilms grown on glass wool, 22 genes were induced significantly (p< or =0.05) compared to suspension cells, including several genes for the stress response ( hslS, hslT, hha, and soxS), type I fimbriae ( fimG), metabolism ( metK), and 11 genes of unknown function ( ybaJ, ychM, yefM, ygfA, b1060, b1112, b2377, b3022, b1373, b1601, and b0836). The DNA microarray results were corroborated with RNA dot blotting. For the biofilm grown on mild steel plates, the DNA microarray data showed that, at a specific growth rate of 0.05/h, the mature biofilm after 5 days in the continuous reactors did not exhibit differential gene expression compared to suspension cells although genes were induced at 0.03/h. The present study suggests that biofilm gene expression is strongly associated with environmental conditions and that stress genes are involved in E. coli JM109 biofilm formation.
利用DNA微阵列研究了大肠杆菌JM109和K12生物膜的基因表达谱。摇瓶中的玻璃棉和连续反应器中的软钢1010平板都被用于形成生物膜。对于在玻璃棉上生长的生物膜，与悬浮细胞相比，有22个基因被显著诱导（p≤0.05），包括几个应激反应基因（hslS、hslT、hha和soxS）、I型菌毛基因（fimG）、代谢基因（metK）以及11个功能未知的基因（ybaJ、ychM、yefM、ygfA、b1060、b1112、b2377、b3022、b1373、b1601和b0836）。DNA微阵列结果通过RNA斑点杂交得到了证实。对于在软钢板上生长的生物膜，DNA微阵列数据表明，在特定生长速率为0.05/h时，连续反应器中5天后的成熟生物膜与悬浮细胞相比未表现出差异基因表达，尽管在0.03/h时有基因被诱导。本研究表明生物膜基因表达与环境条件密切相关，且应激基因参与了大肠杆菌JM109生物膜的形成。
