Compared to planktonic cells, C. acetobutylicum biofilm cells acquired a more efficient phenotype, e.g., improved butanol tolerance and enhanced reaction rate.

Comparative transcriptomic analysis revealed that 16.2% of the C. acetobutylicum genome genes within biofilm cells were differentially expressed, with most genes being up-regulated.

C. acetobutylicum biofilm cells increased metabolic activities probably by up-regulating iron and sulfur uptake and Fe-S cluster biosynthesis genes as well as glycolysis genes.

Genes involved in sporulation, granulose formation, extracellular polymer degradation and pentose catabolisms as well as various other processes were also apparently regulated within the biofilm cells.