Lessons from DNA microarray analysis: the gene expression profile of biofilms.

DNA microarray technology has been used to identify the global gene expression profile of biofilm cells. This is an interesting case study in how DNA microarray technology has advanced the molecular understanding of an understudied research area. DNA microarray analyses have suggested that there may be common responses upon biofilm formation, such as the repression of flagella genes and hyper-expression of genes for adhesion and ribosomal protein. They have also assisted in the identification of transcription factors that affect the formation of biofilms and indicated that there may not be biofilm-specific genes, arguing against biofilm formation being a developmental process. Instead, the DNA microarray data suggest that biofilms may have a unique pattern of gene expression, in which sub-sets of genes expressed in biofilms are also expressed under different planktonic conditions, but only in the biofilm are they all expressed simultaneously.