Costerton J W, Lewandowski Z, Caldwell D E, Korber D R, Lappin-Scott H M
Center for Biofilm Engineering, Montana State University, Bozeman 59717, USA.
Annu Rev Microbiol. 1995;49:711-45. doi: 10.1146/annurev.mi.49.100195.003431.
Direct observations have clearly shown that biofilm bacteria predominate, numerically and metabolically, in virtually all nutrient-sufficient ecosystems. Therefore, these sessile organisms predominate in most of the environmental, industrial, and medical problems and processes of interest to microbiologists. If biofilm bacteria were simply planktonic cells that had adhered to a surface, this revelation would be unimportant, but they are demonstrably and profoundly different. We first noted that biofilm cells are at least 500 times more resistant to antibacterial agents. Now we have discovered that adhesion triggers the expression of a sigma factor that derepresses a large number of genes so that biofilm cells are clearly phenotypically distinct from their planktonic counterparts. Each biofilm bacterium lives in a customized microniche in a complex microbial community that has primitive homeostasis, a primitive circulatory system, and metabolic cooperativity, and each of these sessile cells reacts to its special environment so that it differs fundamentally from a planktonic cell of the same species.
直接观察清楚地表明，在几乎所有营养充足的生态系统中，生物膜细菌在数量和代谢方面都占主导地位。因此，这些固着生物在微生物学家感兴趣的大多数环境、工业和医学问题及过程中占主导地位。如果生物膜细菌仅仅是附着在表面的浮游细胞，那么这一发现就无关紧要了，但它们显然有着深刻的差异。我们首先注意到，生物膜细胞对抗菌剂的抵抗力至少强500倍。现在我们发现，黏附会触发一种σ因子的表达，该因子会解除对大量基因的抑制，从而使生物膜细胞在表型上明显不同于其浮游对应物。每个生物膜细菌都生活在一个复杂的微生物群落中一个定制的微生态位中，这个群落具有原始的内稳态、原始的循环系统和代谢协同作用，并且这些固着细胞中的每一个都会对其特殊环境做出反应，从而使其与同一物种的浮游细胞在根本上有所不同。
